Melanoma:
1. Clinical characteristics
Hoffman S.; Yohn J.; Robinson W.; Norris D.
Colorado University Sch. of Medicine,Denver, CO
United States
Hospital Practice (United States) 1994, 29/6
(37-40+43-44+47-48+50)
The disease is perhaps the clearest instance of
a cancer for which early treatment is crucial.
Increasing knowledge of risk factors (including
brief, intense sun exposure and sunburn damage
early in life) aids the identification of persons
at highest risk-one reason for physicians not to
be pessimistic about the value of urging patients
to limit their sun exposure.
Melanocytic nevi in Turner
syndrome
Becker B.; Jospe N.; Goldsmith L.A.
University of Rochester, Box 697, 601 Elmwood
Avenue,Rochester, NY 14642 United States
Pediatric Dermatology (United States) 1994, 11/2
(120-124)
One morphologic feature of Turner syndrome is
increased numbers of melanocytic nevi; however,
little attention has been given to their
characterization. The development of a melanoma in
one of our patients with Turner syndrome prompted
this study. We prospectively examined 10 patients
with the disease, confirmed by karyotype. All
patients underwent full body skin examination
noting the number, size, distribution, and degree
of clinical atypia of melanocytic nevi.
Representative and unusual lesions were
photographed. An average of 115 nevi were seen,
with the majority measuring 1 to 5 mm. Most were
located on the back and extremities. Clinical
atypia was uncommon. Our patients had larger
numbers of benign-appearing nevi than the general
population. Large numbers of melanocytic nevi is a
risk factor for melanoma , suggesting that these
patients have an increase in one risk factor.
Longitudinal studies are indicated to clarify this
issue; nevertheless, we recommend periodic skin
examinations and the regular use of sunscreens for
individuals with Turner syndrome.
Temporal
changes in the incidence of malignant melanoma:
Explanation from action spectra
Setlow R.B.; Woodhead A.D.
Biology Department, Brookhaven National
Laboratory,Upton, NY 11973 United States
Mutation Research - Fundamental and Molecular
Mechanisms of Mutagenesis (Netherlands) 1994,
307/1 (365-374)
The incidence of malignant cutaneous melanoma
has been increasing for more than 50 years, and is
now rising more rapidly than that of any other
cancer. This increase is not explicable by changes
in the physical environment, particularly by any
observed increase in UVB radiation (290-320 nm).
The distribution of melanomas on the body differs
from the site distribution of nonmelanoma skin
cancer (relatively many more melanomas occur on
areas of the body not chronically exposed to
sunlight, such as the back of the trunk in males,
and the legs in females). This localization of
melanoma , together with its epidemiology, suggest
that a change in lifestyle has contributed to the
fast-rising incidence in many countries. There is
no convenient mammalian animal model for malignant
melanoma . However, certain inter- and
intra-specific hybrids of fish of the genus
Xiphophorus are very sensitive to light-induced
melanomas; we have used them to determine the
wavelengths effective in melanoma induction. The
action spectrum has a relatively very large
component in the UVA region (320-400 nm) compared
to human erythema. Hence, if the human and fish
spectra were similar, the use of sunscreens that
minimize erythema would have little effect in
preventing the induction of melanoma , and if
people using sunscreens expose themselves to
sunlight for longer periods, they will be
increasing dramatically their exposure to these
melanoma -inducing wavelengths. Such
considerations are sufficient to explain the
rising incidence of malignant melanoma and its
distribution on the body.
Effects
of topical tretinoin on dysplastic
nevi
Halpern A.C.; Schuchter L.M.; Elder D.E.;
Guerry IV D.; Elenitsas R.; Trock B.; Matozzo
I.
Department of Dermatology, 3600 Spruce
St,Philadelphia, PA 19104 United States
Journal of Clinical Oncology (United States)
1994, 12/5 (1028-1035)
Purpose: As potential precursors of melanoma
and markers of increased melanoma risk, dysplastic
nevi are suitable targets of strategies for
melanoma chemoprevention. We report the results of
a pilot study of topical retinoic acid in patients
with dysplastic nevi.
Patients and Methods: Five male patients with
dysplastic nevi applied tretinoin to half of the
back for 6 months. Baseline photographs of
dysplastic nevi were compared with posttreatment
photographs and assessed for morphologic change.
At study completion, each subject had four nevi
excised from the treated side and four from the
untreated side of the back. Biopsies were
histologically evaluated for the presence of
dysplasia.
Results: All patients developed signs of
irritation as a result of treatment. One patient
was not compliant with treatment due to skin
irritation. The four compliant patients showed
significant decreases in the clinical atypia of
treated lesions, with concomitant fading and even
disappearance of many treated nevi.
Histologically, only four of 16 treated nevi met
histologic criteria for dysplasia, in comparison
to 13 of 16 untreated nevi.
Conclusion: These results suggest that there is
concomitant clinical and histologic improvement in
a significant percentage of dysplastic nevi
treated with topical tretinoin. However, the
utility of topical tretinoin for chemoprevention
of melanoma is limited by difficulty of
application and associated inflammation. While new
strategies in chemoprevention of melanoma are
explored, sun protection and assiduous avoidance
of sunburn must remain the mainstay of melanoma
prevention.
UV
carcinogenesis: Epidemiology and risk models
Urbach F.
Temple Medical Practices,Fort Washington, PA
19034 United States
Aktuelle Dermatologie (Germany) 1993, 19/12
(368-371)
Direct evidence for induction of non-melanoma
skin cancer by UV irradiation is derived from
animal experiments in mice and rats. A multitude
of epidemiological data confirm this relationship
also for human skin. Tumours are confined to skin
sites with high cumulative sun exposure. Patients
well-protected by constitutively dark skin
pigmentation have a very low incidence of skin
cancer. If natural defensive mechanisms are
disturbed as in albinism or xeroderma pigmentosum,
the risk of skin cancer is extremely high. In some
countries a direct relationship between latitude
and skin cancer with rising incidence in areas
with high sun exposure has been described.
Immunosuppression enhances tumourigenesis. A
reduction of the stratospheric ozone layer by 1%
may result in a 3% increase of squamous cell
carcinoma incidence. Efforts to reduce air
pollution in the troposphere increase UV
irradiance at the earth's surface. Patients at
risk should be encouraged to protect their skin by
suitable clothing, use of sunscreens, and change
of life styles, especially sun exposure habits
during leisure time.
Study of
sunbathing habits in children and adolescents:
Application to the prevention of
melanoma
Grob J.J.; Guglielmina C.; Gouvernet J.; Zarour
H.; Noe C.; Bonerandi J.J.
Service de Dermatologie, Hopital Ste-Marguerite,
270 Boulevard Ste-Marguerite,F-13274 Marseille
Cedex 9 France
Dermatology (Switzerland) 1993, 186/2 (94-98)
Excessive sun exposure in the first 15 years of
life has been shown to be a deter rninant risk
factor for melanoma . This study was conducted on
a randomly selected sample of 200 adolescents
(13-14 years old) and 150 children (3 years old)
in Marseille (South of France). Children and
adolescents were examined and interviewed (mothers
answered for young children). Our results show
that a large number of highly sensitive children
were not identified as such by their parents and
most adolescents do not realize or at least admit
being highly sun sensitive. Adequate sun
protection measures were used in only 63% of
3-year-olds and 38% of adolescents. With reference
to their constitutional skin sensitivity and
taking into account their possible use of
effective sun protection measures, 33% of the
children and 62% of the adolescents were highly
overexposed. Only good sun protection habits of
the mother were predictive of acceptable sun
exposure in children. In the adolescents the
predictive variables were sun protection habits of
the father and sunbathing only to obtain a tan.
The main reason why adolescents sunbathed was
embellishment. Conversely, most mothers said that
they exposed their young children to the sun for
health. Many adolescents and mothers were
reasonably well informed but considered the risk
of sun exposure to be exaggerated by the media.
These results may be important to determine the
targets of future melanoma prevention
campaigns.
Solar
radiation protection for outdoor
workers
Webb G.
Div of Workplace Health and Safety, PO Box
6665,Cairns, QLD 4870 Australia
Journal of Occupational Health and Safety -
Australia and New Zealand (Australia) 1992, 8/6
(479-485)
Ultraviolet radiation in sunlight presents a
potential risk to health for outdoor workers. The
paper examines the issues of health effects of
solar radiation, including skin cancer,
identification of high-risk groups for skin
cancer, legal implications for employers in the
context of occupational health and safety
legislation, and measures for prevention or
minimisation of solar radiation exposure of
outdoor workers. The issue of worker compliance
with protective measures is explored, using the
Health Belief Model as a framework.
Multidisciplinary treatment of facial
skin cancer
Calhoun K.H.; Wagner R.F.
Department of Otolaryngology, University of Texas
Medical Branch, Galveston, TX 77550 United
States
Texas Medicine (United States) 1991, 87/12
(64-69)
Skin cancer incidence is increasing rapidly. We
outline the indications for and advantages of
diagnostic techniques and treatments, including
curettage and electrodesiccation, surgical
excision, Mohs' micrographic surgery, cryosurgery,
radiation therapy, interferon injection, and
photodynamic therapy. We describe our
interdisciplinary treatment protocol for skin
cancer treatment and emphasize avoidance of the
sun and early treatment of photodamaged skin. This
treatment includes oral retinoids, topical
tretinoin (Retin-A), 5 fluorouracil, and chemical
peels performed with trichloroacetic acid or
phenol.
Sun
protection in newborns: A comparison of
educational methods
Bolognia J.L.; Berwick M.; Fine J.A.; Simpson
P.; Jasmin M.
Department of Dermatology, Yale University,
School of Medicine, 333 Cedar St,New Haven, CT
06510 United States
American Journal of Diseases of Children (United
States) 1991, 145/10 (1125-1129)
We investigated the effect of education on the
sun exposure of newborns. Mothers of healthy
newborns (n = 275) were enrolled in the spring of
1989 and interviewed by telephone in the fall of
1989. The mothers were divided into a control
group, a low-level intervention group, and a
high-level intervention group. Both the low-level
and high-level interventions succeeded in reducing
the amount of time the newborns were allowed to
spend in direct sunlight. Both types of
intervention also resulted in reduced sun exposure
time for the mothers. Although the number of
mothers who used sunscreen was approximately the
same in all three groups, when sunscreen use was
controlled for, the intervention groups spent
significantly less unprotected time in the sun
than the control group. The mothers and newborns
in both intervention groups simply spent less time
outdoors.
Malignant melanoma: Aetiological
importance of individual pigmentation and sun
exposure
Beitner H.; Norell S.E.; Ringborg U.;
Wennersten G.; Mattson B.
Department of Dermatology, Karolinska
Hospital,S-104 01 Stockholm Sweden
British Journal of Dermatology (United Kingdom)
1990, 122/1 (43-51)
A case-control study of cutaneous malignant
melanoma (CMM) was based on 523 incident cases and
505 age- and sex-matched controls selected from
the general population. The purpose was to
investigate the relative risk of developing CMM
associated with different sun habits and
indicators of pigmentation, such as skin type, eye
colour and hair colour. Compared to people with
black hair, blonde subjects had a relative risk of
74.4 (95% confidence interval, 45.8-120.8).
Associations with skin type and eye colour were
considerably weaker. Relative risks of about
1.5-2.5 were found for certain sun habits. The
results suggest that in a population of Caucasian
origin with a predominantly fair complexion,
pigmentary status characterized by hair colour is
a far more important aetiological factor than sun
habits.
Sunscreens: Topical and systemic
approaches for protection of human skin against
harmful effects of solar radiation
Pathak M.A.
Dept. Dermatol., Harvard Med. Sch., Massachusetts
Gen. Hosp., Boston, MA 02114 United States
Journal of the American Academy of Dermatology
(United States) 1982, 7/3 (285-314)
This review deals with topical and systemic
approaches for protection of human skin against
the harmful effects of solar radiation. Two
concerns about the deleterious effects of sun
exposure involve: (1) acute effects (e.g., sunburn
and drug-induced phototoxicity) and (2) potential
long-term risks of repeated sun exposures leading
to development of solar elastosis, keratoses,
induction of both nonmelanoma and melanoma skin
cancer, and alteration of immune responses and
functions. Action spectra of normal and abnormal
reactions of human skin to acute and chronic
effects of solar radiation are presented with a
view to helping the physician prescribe the
appropriate sunscreens. Factors that influence
acute effects of sunburn are reviewed. Various
artificial methods effective in minimizing or
preventing harmful effects of solar radiation,
both in normal individuals and in patients with
photosensitivity-related problems, are discussed.
Emphasis is placed on the commercially available
chemical sunscreens and their properties. Sun
protection factor (SPF) values of several
brand-name formulations determined with a solar
simulator under indoor conditions (laboratory) and
with solar radiation under natural, field
conditions are prevented. Factors responsible for
variations of SPF values observed under indoor and
outdoor conditions are reviewed. Systemic
photoprotective agents and their limitations are
outlined. The photobiology of melanin pigmentation
(the tanning reaction) is briefly discussed, with
emphasis on the dangers of using quick-tanning
lotions for stimulation of the tanning
reaction.
Inhibition of cyclobutane pyrimidine
dimer formation in epidermal p53 gene of
UV-irradiated mice by
alpha-tocopherol.
Chen W; Barthelman M; Martinez J; Alberts D;
Gensler HL
Department of Radiation Oncology, College of
Medicine, University of Arizona, Tucson 85724,
USA.
Nutr Cancer (United States) 1997, 29 (3)
p205-11
Mutations or alterations in the p53 gene have
been observed in 50-100% of ultraviolet light
(UV)-induced squamous cell carcinoma in humans and
animals. Most of the mutations occurred at
dipyrimidine sequences, suggesting that pyrimidine
dimers in the p53 gene play a role in the
pathogenesis of cutaneous squamous cell carcinoma.
We previously showed that topical alpha-tocopherol
prevents UV-induced skin carcinogenesis in the
mouse. In the present study we asked whether
topical alpha-tocopherol reduces the level of
UV-induced cyclobutane pyrimidine dimers in the
murine epidermal p53 gene. Mice received six
dorsal applications of 25 mg each of
alpha-tocopherol, on alternate days, before
exposure to 500 J/m2 of UV-B irradiation. Mice
were killed at selected times after irradiation.
The level of dimers in the epidermal p53 gene was
measured using the T4 endonuclease V assay with
quantitative Southern hybridization. Topical
alpha-tocopherol caused a 55% reduction in the
formation of cyclobutane pyrimidine dimers in the
epidermal p53 gene. The rate of reduction of
pyrimidine dimers between 1 and 10 hours after
irradiation was similar in UV-irradiated mice,
regardless of alpha-tocopherol treatment.
Therefore, the lower level of cyclobutane
pyrimidine dimers in UV-irradiated mice treated
with alpha-tocopherol than in control
UV-irradiated mice resulted from the prevention of
formation of the dimers, and not from enhanced
repair of these lesions. Our results indicate that
alpha-tocopherol acts as an effective sunscreen in
vivo, preventing the formation of premutagenic DNA
lesions in a gene known to be important in skin
carcinogenesis.
Sunscreens protect from UV-promoted
squamous cell carcinoma in mice chronically
irradiated with doses of UV radiation insufficient
to cause edema.
Bestak R; Halliday GM
Department of Medicine (Dermatology), University
of Sydney, Royal Prince Alfred Hospital,
Camperdown, New South Wales, Australia.
Photochem Photobiol (United States) Jul 1996, 64
(1) p188-93
Previously we reported that the broad-spectrum
sunscreen microfine titanium dioxide (MTD) could
completely protect C3H/HeJ mice from UV
radiation-induced immunosuppression to a contact
sensitizer. In contrast, 2-ethylhexyl
p-methoxycinnamate (2-EHMC), a UVB-absorbing
sunscreen , only partially protected the skin
immune system. In this study we investigated
further this differential protection of the skin
immune system by comparing the ability of 2-EHMC
and MTD to protect these mice from the promotion
phase of tumorigenesis. The mice were initiated
using a single subcarcinogenic dose of
7,12-dimethylbenz(alpha)anthracene (DMBA) followed
by promotion with chronic low-dose solar-simulated
UV radiation for 32 weeks. We used doses of UV
insufficient to cause edema in order to simulate
daily human exposure to solar UV radiation. Mice
were observed for the appearance of squamous cell
carcinomas for 48 weeks. The DMBA-initiation alone
and DMBA-initiated, sunscreen -treated groups did
not develop tumors. Ultra-violet alone induced the
appearance of tumors in 46% of mice at week 48 and
therefore some tumors were initiated by UV.
Initiation with DMBA prior to UV irradiation
enhanced tumorigenesis such that 87% of mice at
week 48 had tumors. Both 2-EHMC and MTD completely
protected these mice from UV-induced promotion as
well as from complete carcinogenesis despite the
different UV-absorption spectra of the sunscreens
and their differential abilities to protect from
UV-induced immuno-suppression. Furthermore, we
have shown that, if UV exposure is not increased
to compensate for tolerance to edema, protection
from tumorigenesis is afforded by sunscreens.
Cell
survival and shuttle vector mutagenesis induced by
ultraviolet A and ultraviolet B radiation in a
human cell line.
Robert C; Muel B; Benoit A; Dubertret L;
Sarasin A; Stary A
Laboratory of Molecular Genetics, Institut de
Recherches sur le Cancer, Villejuif, France.
J Invest Dermatol (United States) Apr 1996, 106
(4) p721-8
Although it is known that sunlight is
carcinogenic,few molecular data are available
concerning the mutagenic effects of ultraviolet
(UV) B (290-320 nm) and UVA (320-400 nm) radiation
in human cells. To analyze the biologic effects of
UVA and UVB, we irradiated the 293 human cell
line, derived from adenovirus-transformed human
embryonic kidney cells, in which we had stably
introduced a shuttle vector harboring the lacZ'
bacterial gene as the mutagenesis target.
Identical cell survival occurred after UVA doses
700-fold higher than UVB. This comparable to the
UVA/UVB ratio that reaches the basal cell layer of
the skin after sunlight exposure with UVB
sunscreen . The frequency of UVA- and UVB- induced
mutations increased with the UV dose as cell
survival decreased. At cell survival levels
greater than 10%, UVA and UVB induced similar
frequencies of mutations in the episomal lacZ
gene, whereas for cell survival lower than 10%,
UVA induced twice as many mutations as UVB.
Sequence analysis of 81 independent lacZ mutants
(36 UVA- and 45 UVB-induced) revealed specific
characteristics for some UV-induced-mutations,
particularly for UVB. Mutations at A/T base pairs
were induced more frequently by UVA than by UVB.
The UVA-induced mutation spectrum that we have
observed in human cells may help help to elucidate
the mechanism of skin carcinogenesis.
Sun
protection and sunscreen use after surgical
treatment of basal cell carcinoma.
Harth Y; Ulman Y; Peled I; Friedman-Birnbaum
R
Department of Dermatology, Rambam Medical Center,
Haifa, Israel.
Photodermatol Photoimmunol Photomed (Denmark) Aug
1995, 11 (4) p140-2
Sixty-three patients (mean age 54 +/- 9 years)
who were treated for a basal cell carcinoma (BCC)
and 54 control subjects (mean age 51 +/- 11 years)
filled out detailed questionnaires on their sun
exposure and sun protection habits. Patients were
given the questionnaires at least 1 year after
their skin tumors had been excised. Differences
between patients and controls in mean age, gender,
Fitzpatrick's skin type and eye and hair color
were statistically nonsignificant. The level of
education was high in both patients and controls
(mean of 13.4 +/- 3.1 school years). Differences
in education were statistically nonsignificant. We
found that both patients and controls were
knowledgeable about the role of sunscreens in
preventing skin tumors (79% and 83% respectively)
and in preventing sun-induced aging (90% and 85%
respectively). Significantly more patients used
sunscreens regularly (64%) compared with controls
(36%). Nevertheless, our data show no
statistically significant differences between the
sun exposure habits of the patients previously
treated for BCC and controls. Moreover, we found
that, although 82% of the patients declared that
they tried to avoid sun, only 49% regularly wore
hats or shirts with long sleeves in the summer
(19%). Sixty-two percent of the patients used two
or fewer bottles of sunscreens per year, which is
inadequate for effective year-round sun
protection. In addition, we found that many
patients, as well as the controls, applied
sunscreens only once a day (57% and 46%
respectively), did not reapply after swimming
(58%, 74% respectively), and did not use
sunscreens in the winter (49%, 61%). Our data show
that, although patients after BCC removal have a
significantly higher sunscreen use compared with
controls, the amount and methods of application
are less than adequate. Moreover, other simpler
methods to prevent photodamage, such as simple sun
avoidance or the use of protective clothing, are
often neglected.
A
prospective study of incident squamous cell
carcinoma of the skin in the nurses' health
study
Grodstein F; Speizer FE; Hunter DJ
Channing Laboratory, Department of Medicine,
Brigham and Women's Hospital, Harvard Medical
School, Boston, MA, USA.
J Natl Cancer Inst (United States) Jul 19 1995,
87 (14) p1061-6
BACKGROUND: Few epidemiologic studies are
available that quantify the magnitude of the risk
of squamous cell carcinoma (SCC) of the skin
associated with sun exposure and related factors
such as skin type. In addition, several studies
have found an association between cigarette
smoking and SCC.
PURPOSE: We prospectively examined the risk of
developing SCC in relation to phenotype and the
effects of sun exposure, as well as to cigarette
smoking and other factors, during 8 years of
follow-up in a cohort of 107,900 predominantly
white women aged 30-55 years at base line in
1976.
METHODS: Questionnaires regarding medical
history and health-related variables were sent to
Nurses' Health Study participants every 2 years,
beginning in 1976. Information on constitutional
factors (natural hair color, childhood and
adolescent tendency to sunburn and tan, and
lifetime number of severe sunburns), lifestyle
factors (regular time spent outdoors in the summer
and sunscreen use), the state lived in at birth
and at ages 15 and 30 years, and cigarette smoking
habits were ascertained by questionnaire. A total
of 197 women with first-incident, histologically
confirmed, invasive SCCs that were diagnosed from
1982 to 1990 were included in this analysis.
Multivariate analysis using proportional hazards
models was used to calculate the relative risks
(RRs) and corresponding 95% confidence intervals
(CIs), with adjustment for confounders.
RESULTS: The risk of SCC was increased in women
living in California (RR = 1.8; 95% CI = 1.3-2.6)
and Florida (RR = 2.1; 95% CI = 1.1-3.9) at base
line, compared with those living in the
northeastern states. This risk was higher for
women living in those states at birth and at 15
years of age (RR = 2.5; 95% CI = 1.4-4.4 for
California and RR = 3.0; 95% CI = 0.7-1.2 for
Florida). Red (RR = 2.0; 95% CI = 1.1-3.7) and
light brown (RR = 1.7; 95% CI = 1.2-2.4) hair
colors were associated with an increased risk of
SCC, compared with dark brown hair. After
adjusting for the number of sunburns, women who
tended to burn after 2 or more hours of sun
exposure as children had a slightly higher risk of
SCC than those who never burned (RR = 1.5; 95% CI
= 0.9-2.5 for burn and RR = 1.1; 95% CI = 0.6-2.0
for painful burn), although the actual number of
severe burns appeared to be a more important
factor (RR = 2.4; 95% CI = 1.5-4.0 for six or more
burns). Finally, current cigarette smokers showed
a 50% increase in the risk of SCC compared with
never smokers (RR = 1.5; 95% CI = 1.1-2.1).
CONCLUSION: Exposure to the sun leading to
sunburn, particularly at early ages, should be
avoided to decrease the risk of incident SCC.
High
sun protection factor sunscreens in the
suppression of actinic neoplasia.
Naylor MF; Boyd A; Smith DW; Cameron GS;
Hubbard D; Neldner KH
Department of Dermatology, University of Oklahoma
Health Sciences Center, Oklahoma City.
Arch Dermatol (United States) Feb 1995, 131 (2)
p170-5
BACKGROUND AND DESIGN: A controlled trial was
undertaken from December 1987 to December 1990 to
test the hypothesis that a strong sunscreen can
reduce the number of cancerous and precancerous
skin lesions. Candidates were selected from a
high-risk population attending either a
university- or Veterans Affairs-based dermatology
practice in Lubbock, Tex, for a prospective,
double-blind, controlled trial of daily
application of sunscreen vs placebo over a 2-year
period. Participants were asked to volunteer if
they had demonstrated premalignant changes
(actinic keratoses) or nonmelanoma skin cancer
(basal cell carcinoma or squamous cell carcinoma),
had continuing sun exposure, and were not using
sunscreen on a regular basis. Fifty-three
volunteers were initially enrolled in the study,
and 37 came for the final 24-month visit.
RESULTS: The rate of appearance of new
precancerous skin lesions was less for the
treatment group than for control subjects. People
with darker skin had fewer actinic keratoses,
women had fewer lesions than men, and people with
fewer lesions at enrollment had fewer lesions
during the study. The numbers of new nonmelanoma
skin cancers appearing during the study period
were too small for statistical analysis.
CONCLUSIONS: The regular use of sunscreens can
significantly reduce cutaneous neoplasia, as
indicated by its suppression of precancerous
lesions. A longer and/or larger study would be
necessary to demonstrate an effect on malignant
lesions.
The
Nambour Skin Cancer and Actinic Eye Disease
Prevention Trial: design and baseline
characteristics of participants.
Green A; Battistutta D; Hart V; Leslie D; Marks
G; Williams G; Gaffney P; Parsons P; Hirst L;
Frost C; et al
Queensland Institute of Medical Research,
Brisbane, Australia.
Control Clin Trials (United States) Dec 1994, 15
(6) p512-22
The Nambour Skin Cancer and Actinic Eye Disease
Prevention Trial (the Nambour Trial) is a field
trial conducted in an unselected adult population
in Australia. Using a randomized 2 x 2 factorial
design, the principal aim is to evaluate whether
regular use of high-protection sunscreen and/or
dietary supplementation with beta-carotene (30 mg
daily) can alter the incidence rates of basal cell
carcinomas and squamous cell carcinomas of the
skin over a minimum follow-up time of 4.5 years.
Changes in the incidence of solar keratoses and
actinic eye disease and the rate of photoaging
after intervention will also be investigated. In
1992, 1626 participants between the ages of 25 and
75 years were enrolled, all of whom had been
randomly selected from residents of the
southeastern Queensland township of Nambour for an
earlier skin cancer prevalence survey. This paper
describes the background to the trial and its
design, with respect to evaluation of effects on
actinic skin disease, and documents the baseline
characteristics of participants recruited into the
Nambour Trial.
Photodamage, photoaging and
photoprotection of the skin.
Guercio-Hauer C; Macfarlane DF; Deleo VA
State University of New York Health Science
Center at Brooklyn.
Am Fam Physician (United States) Aug 1994, 50 (2)
p327-32, 334
Overexposure to ultraviolet and visible
radiation causes sunburn. Aspirin and other
nonsteroidal anti-inflammatory drugs, cool baths
and topical steroids offer only mild relief.
Long-term sun exposure causes chronic inflammatory
skin changes. Photodamage, rather than the normal
aging process, may account for 90 percent of
age-associated cosmetic skin problems. Physicians
should stress to their patients that all
ultraviolet exposure (including sun beds and
tanning salons) causes skin damage. Regular
sunscreen use during childhood and adolescence may
result in an 80 percent reduction in the lifetime
incidence of ultraviolet-induced skin damage,
including nonmelanoma skin cancers. (17 Refs.)
Reduction of solar keratoses by
regular sunscreen use
Thompson SC; Jolley D; Marks R
Anti-Cancer Council of Victoria, Carlton,
Australia.
N Engl J Med (United States) Oct 14 1993, 329
(16) p1147-51
BACKGROUND. The incidence of and mortality from
skin cancer are increasing in many countries. In
view of the added concern about ozone depletion,
many organizations are promoting the regular use
of sunscreens to prevent skin cancer, despite the
absence of evidence that these products have this
effect. Solar (actinic) keratosis is a precursor
of squamous - cell carcinoma of the skin.
METHODS. We conducted a randomized, controlled
trial of the effect on solar keratoses of daily
use of a broad-spectrum sunscreen cream with a
sun-protection factor of 17 in 588 people 40 years
of age or older in Australia during one summer
(September 1991 to March 1992). The subjects
applied either a sunscreen cream or the base cream
minus the active ingredients of the sunscreen to
the head, neck, forearms, and hands.
RESULTS. The mean number of solar keratoses
increased by 1.0 per subject in the base-cream
group and decreased by 0.6 in the sunscreen group
(difference, 1.53; 95 percent confidence interval,
0.81 to 2.25). The sunscreen group had fewer new
lesions (rate ratio, 0.62; 95 percent confidence
interval, 0.54 to 0.71) and more remissions (odds
ratio, 1.53; 95 percent confidence interval, 1.29
to 1.80) than the base-cream group. There was a
dose-response relation: the amount of sunscreen
cream used was related to both the development of
new lesions and the remission of existing
ones.
CONCLUSIONS. Regular use of sunscreens prevents
the development of solar keratoses and, by
implication, possibly reduces the risk of skin
cancer in the long-term.
Minimising the risks of PUVA
treatment.
van Praag MC; Tseng LN; Mommaas AM; Boom BW;
Vermeer BJ
Department of Dermatology, Sint Franciscus
Gasthuis, Rotterdam, The Netherlands.
Drug Saf (New Zealand) May 1993, 8 (5) p340-9
Psoralen photochemotherapy (PUVA) is a
combination of orally administered psoralen and
long wave ultraviolet-A radiation (UVA), and is
one of the most effective forms of therapy for
psoriasis. The unwanted effects of PUVA therapy
can be divided into short and long term adverse
effects. The short term adverse effects include
erythema, pruritus, nausea and headache. While
short term adverse effects are limited and
reversible after discontinuation of treatment,
potential long term adverse effects such as
chronic actinic skin damage, dyskeratotic and
precancerous skin conditions, nonmelanoma skin
cancer, immunological alterations and cataract
formation are of greater concern. Long term risks
associated with PUVA therapy can be minimised by
several measures. Careful patient selection is
mandatory; for example, patients with chronic
actinic damage and a history of skin cancer may
bear a higher risk for the development of new
cancers, and previous arsenic intake and ionising
radiation also increase the risk of nonmelanoma
skin cancers. Certain drug combinations make it
possible to lower the UVA dose, which is important
because of the dose-dependent increase in the
incidence of squamous cell carcinomas in patients
treated with PUVA. It has been demonstrated that
200 treatments or a total UVA dose of 1200 J/cm2
seems to be the threshold for development of
nonmelanoma skin cancer. Shielding male genitalia
during PUVA treatment is essential because of the
increased risk of genital squamous cell
carcinomas. Yearly dermatological examination to
detect skin cancer at an early stage is highly
advisable. Sunscreen use, protective clothing and
avoidance of sun exposure reduce the uncontrolled
dose of solar UV radiation. Other psoralens with a
less carcinogenic potential can be used.
UVA-opaque sunglasses during the entire period of
increased photosensitivity after psoralen
ingestion help avoid cataract formation.
Assignment to PUVA ought to be based on the
risk-benefit ratio for the individual patient and
should be limited to those who can be monitored
and controlled by informed, competent and
conscientious physicians. (56 Refs.)
Effect
of immunosuppressive agents and sunscreens on UV
carcinogenesis in the hairless mouse.
Reeve VE; Greenoak GE; Gallagher CH; Canfield
PJ; Wilkinson FJ
Aust J Exp Biol Med Sci (Australia) Dec 1985, 63
(Pt 6) p655-65
The effect of two immunosuppressive agents,
azathioprine and cyclophosphamide, with and
without UVB sunscreen protection on UV-induced
skin carcinogenesis was studied in the albino
hairless mouse. In a daily treatment regime
spanning 9 weeks, groups of mice were
immunosuppressed with either drug, and were
exposed to minimally erythemal doses of a light
source simulating the UV portion of the solar
spectrum. The accumulated UV exposure alone
induced skin tumours in 77% of mice. Azathioprine,
but not cyclophosphamide, significantly enhanced
the incidence of UV tumorigenesis. Photoprotection
by topical application of one of two commonly used
UVB sunscreens, 2-ethyl-hexyl-p-methoxycinnamate
(2-EHMC) or octyl-N-dimethyl-p -aminobenzoate
(o-PABA), reduced the UV tumour incidence to zero
in immunologically normal mice and to 8-15% in
immunosuppressed mice. Unexpressed latent tumour
initiations were revealed in all sunscreen
-protected groups by the subsequent application of
a tumour promoter, croton oil. In immunologically
normal mice 2-EHMC had allowed initiations in 39%
of UV-irradiated mice, and o-PABA in 16.5%.
However, in UV-irradiated mice immunosuppressed
with azathioprine there had been initiations in
78% of mice protected with 2-EHMC and 65% of mice
protected with o-PABA. Photoprotected mice
immunosuppressed with cyclophosphamide did not
show the same increase in UV-initiations (22% with
2-EHMC, 23% with o-PABA). These results provide
evidence that azathioprine increases the
susceptibility of the skin to UV carcinogenesis.
However, UVB sunscreens afford effective
protection from overt tumour expression in the
absence of a tumour promoter.
Sunscreen protection for lip mucosa:
a review and update.
Lundeen RC; Langlais RP; Terezhalmy GT
J Am Dent Assoc (United States) Oct 1985, 111 (4)
p617-21
It has been stated that the key to prevention
of oral cancer is to avoid the "five Ss: smoking,
spirits, spices, sepsis, and syphilis." There is
certainly enough evidence to add another
"S"--sunlight. Although there is a paucity of
information in the dental literature on the use of
sunscreens, the following dermatologic
recommendation is noteworthy: "Persons with Skin
Types I and II should never sunbathe and should
adopt a program of daily application of effective
sunscreens (SPF 15) as a habit and from an early
age--in much the same manner as daily brushing of
the teeth is adopted to prevent dental caries."
The dentist should advise patients at high risk
for squamous cell carcinoma and those with
recurrent herpes labialis to use a sunscreen for
the lips of at least SPF 15. The best sunscreen
formulation at the present time is a combination
of either PABA or an ester of PABA along with a
benzophenone. A frequent combination seen on
product labels is Padimate O and oxybenzone.
Sunscreens should be used year-round on the lips
with two applications 1 hour before sun exposure,
and hourly reapplication while in the sun. If the
convenience of a "lipstick" product is not
important to the patient, then a skin product of
the liquid or gel type should be used. If the
appearance is not important, a white opaque cream
containing titanium dioxide, talc, or zinc oxide
may be used as a physical barrier. Women may use
an opaque lipstick, but should first apply a
chemical sunscreen of at least SPF 15.(ABSTRACT
TRUNCATED AT 250 WORDS)
Psoralen-containing sunscreen is
tumorigenic in hairless mice.
Cartwright LE; Walter JF
J Am Acad Dermatol (United States) Jun 1983, 8
(6) p830-6
Sunscreens containing 5-methoxypsoralen (5-MOP)
are currently being marketed to promote tanning by
inducing psoralen-mediated ultraviolet (UV) A
(320-400 nm) melanogenesis. The rationale is that
this may prevent UVB (290-320 nm)
radiation-induced skin damage. However, mouse
studies have shown that 5-MOP has the same
cutaneous photocarcinogenic potential as
8-methoxypsoralen. In addition, the
5-MOP--containing sunscreen Sun System III (SS
III), when combined with UVA, induces epidermal
ornithine decarboxylase activity, an enzyme
associated with tumor promotion. Therefore, we
investigated whether SS III had sufficient
psoralen concentration to be tumorigenic in
hairless mice exposed to chronic, intermittent UVA
radiation. SS III was applied to hairless mice 5
days per week for 20 weeks. After each application
the mice were exposed to 2.5 to 10 joules/cm2 UVA
radiation. All test groups developed atypical
squamous papillomas in direct proportion to the
dosage of UVA radiation received. A shorter
latency period for tumor development was seen with
larger UVA doses. Test animals followed up to 1
year developed invasive squamous cell tumors.
Control groups (SS III without UVA and UVA without
SS III) remained free of tumors. Animals receiving
SS III plus UVA developed persistent skin
thickening and increased dermal cyst formation
similar to that reported with chronic exposure to
UVB, a known carcinogenic wavelength.
Over-the-counter sunscreens containing 5-MOP do
contain sufficient psoralen concentrations to
cause cutaneous phototoxicity and
photocarcinogenicity in mice, and their use in
humans should be discouraged in the interest of
preventing further UV-induced skin damage and skin
cancer.
Sunscreens for delay of ultraviolet
induction of skin tumors.
Wulf HC; Poulsen T; Brodthagen H; Hou-Jensen
K
J Am Acad Dermatol (United States) Aug 1982, 7
(2) p194-202
Sunscreens with different sun protection
factors (SPFs) have been tested for their
capability of delaying or preventing actinic
damage and skin cancer development in groups of
hairless, pigmented mice exposed to artificial
ultraviolet (UV) light of increasing intensity.
The dose delivered was less than or equal to 1
minimal erythema dose (MED) in the group of
untreated mice, so that the mice to which
sunscreens were applied never obtained a sunburn
after UV exposure. The quality of UV light was
similar to bright midday sun at a latitude of 56
degrees (city of Copenhagen). Tumorigenesis was
demonstrated to be delayed corresponding to the
SPF claimed by the manufacturer, but almost all of
the UV-irradiated mice developed skin tumors.
Histologic examination revealed actinic
degeneration and tumors of squamous cell type with
marked variation in differentiation. Metastases to
lymph nodes and lungs were found in only 10%.
Toxic reactions, such as eczematous-like skin
reactions, dark coloring, and amyloidosis, were
observed predominantly in the group treated with
the sunscreen of highest SPF value. Long-term
investigations seem to be necessary to unveil
these problems--in particular, the specific SPF
value, in sunscreens, that should be recommended
to the public for prevention or delay of actinic
damage and/or cancer development.
Eyelid
cancers
Soparkar C.N.S.; Patrinely J.R.
Dr. C.N.S. Soparkar, Plastic Eye Surgery
Associates, PLLC, 6500 Fannin Street, Houston, TX
77030 United States
Current Opinion in Ophthalmology (United States)
1998, 9/5 (49-53)
Eyelid cancers, like most malignancies, are on
the rise, creating an ever-enlarging population of
patients with these diseases. Trends in eyelid
cancer diagnosis, prognostic evaluation,
prevention, and management are reviewed. Special
emphasis is placed upon understanding perineural
invasion by squamous cell carcinoma, the role of
genetic mutations in eyelid cancer development and
prognosis, and new techniques for total upper
eyelid reconstruction.
Axillary basal cell cacrinoma: A need
for full cutaneous examination
English III J.C.; Canchola D.R.; Finley E.M.
Dr. J.C. English III, 1940 Avalon Ct., Colorado
Springs, CO 80919 United States
American Family Physician (United States) 15 APR
1998 , 57/8 (1860-1864)
Basal cell carcinoma is the most common skin
malignancy. While this lesion most often occurs in
sun-exposed areas of the skin, it can also develop
in sites that are not usually exposed to sunlight
or artificial ultraviolet radiation, such as the
breast, palm or groin. A periodic complete
examination of the skin should be performed to
ensure that atypical presentations of basal cell
carcinoma are not overlooked or misdiagnosed.
Treatment options include curettage and
desiccation, cryosurgery, surgical excision,
radiotherapy and Mohs micrographic surgery.
Sunlight and carcinogenesis:
Expression of p53 and pyrimidine dimers in human
skin following UVA I, UVA I + II and solar
simulating radiations
Burpen R.; Scaletta C.; Frenk E.; Panizzon
R.G.; Applegate L.A.
L.A. Applegate, Department of Dermatology,
Laboratory of Photobiology, University Hospital,
CH-1011 Lausanne Switzerland
Lee.Laurent-Applegate@chuv.hospvd.ch
International Journal of Cancer (United States)
13 APR 1998, 76/2 (201-206)
DNA damage by UV radiation plays an essential
role in skin cancer induction. We report that even
sub-erythemal doses of solar simulating radiation,
are capable of inducing substantial nuclear
damage, namely pyrimidine dimers and p33 induction
in human skin in situ. The quantity and
distribution of p53 induced in human skin by UV
radiation depended highly on the waveband and dose
of UV used. Solar simulating radiation induced
very high levels of p53 throughout all layers in
epidermal keratinocytes 24 hr following an
erythemal dose (230 +/- 15.9/1000 cells), and the
induction followed a dose response. Following UVA
I + II and UVA I radiations, p53 expression was
approximately half of that seen with equivalent
biological doses of solar simulating radiation
(63.5 +/- 28.5 and 103 +/- 15.9, respectively).
Expression of p53 was seen in basal cell
keratinocytes at lower doses of UVA, but all
layers of the epidermis were affected at higher
doses. Pyrimidine dimer induction, however, was
seen to be the same for equivalent biological
doses of UVA I, UVA I + II and solar simulating
radiations, which coincides with previous findings
that pyrimidine dimers initiate the erythemal
response and are implicated in skin
carcinogenesis. When equivalent biological doses
of pure UVA are used with no UVB contamination,
significant nuclear alterations occur in human
skin in situ, which can approach those seen with
UVB radiation. Our results suggest that DNA damage
assessed in vivo by immunohistochemistry could
provide a very sensitive endpoint for determining
the efficacy of protective measures, such as
sunscreens or protective clothing, against both
UVB- and UVA-induced damage in human skin.
Long-term efficacy and safety of
Jessner's solution and 35% trichloroacetic acid vs
5% fluorouracil in the treatment of widespread
facial actinic keratoses
Witheiler D.D.; Lawrence N.; Cox S.E.; Cruz C.;
Cockerell C.J.; Freemen R.G.; Brody H.J.
Dr. D.D. Witheiler, 221 W. Colorado Blvd.,
Dallas, TX 75208 United States
Dermatologic Surgery (United States) 1997, 23/3
(191-196)
BACKGROUND. Few studies have examined the
long-term efficacy of fluorouracil (FU) or
chemical peels for the treatment of actinic
keratoses (AK). Our earlier work examined the
efficacy and safety of a medium-depth chemical
peel compared with the standard regimen of topical
FU in the treatment of widespread facial AK
through 12 months.
OBJECTIVES. To determine long-term efficacy of
both treatments by extending our observations
through 32 months.
METHODS. Fifteen patients with severe facial
actinic damage were treated on the left side with
a single application of Jessner's solution and 35%
trichloroacetic acid and on the right side with
twice daily applications of 5% FU cream for 3
weeks. Parameters evaluated at 1, 6, 12, and 32
months included counts of visible AK, random skin
biopsies from both treatment areas, development of
intercurrent neoplasms, and surveys assessing sun
exposure.
RESULTS. Eight patients were available for
reevaluation at 32 months. Both treatment sides
showed a reduction in mean number of AK at 12
months followed by an increase in mean AK number
between 12 and 32 months. Improvements in biopsies
of clinically actinically damaged skin were seen
in keratinocytic atypia, hyperkeratosis,
parakeratosis, and inflammation at all treatment
times during the study with both treatments. Three
squamous cell carcinomas developed in the patients
after initial treatment; one developed on the side
treated with the peel, and two developed on the
side treated with fluorouracil. Surveys failed to
demonstrate an association between sun exposure
and clinical response.
CONCLUSION. Based on these findings, patients
with widespread actinic keratoses treated with
medium-depth chemical peel or with 5% FU should be
reevaluated yearly or every 1.5 years for
reappearance of AK and retreatment.
Nonmelanoma skin cancer: Risks,
treatment options, and tips on
prevention
Kibarian M.A.; Hruza G.J.
One Barnes Hospital Plaza,St Louis, MO 63110
United States
Postgraduate Medicine (United States) 1995, 98/6
(39-40+45-46+48+55-56+58)
The incidence of nonmelanoma skin cancer is
rapidly increasing. With early diagnosis and
treatment, almost all basal cell and squamous cell
carcinomas can be cured. Premalignant actinic
keratoses are treated with cryosurgery; the COinf
2 laser is the treatment of choice for actinic
cheilitis. Generally; nonmelanoma skin cancer can
be effectively treated with excision,
electrodesiccation and curettage, cryosurgery, or
radiation therapy; 5-year cure rates are over 90%.
Large, locally recurrent, and aggressive lesions,
as well as lesions located in the central face,
are best managed with Mohs' surgery; 5-year cure
rates as high as 99% have been reported. Patient
education about the dangers of sun exposure and
tanning salons can potentially reduce the
incidence of nonmelanoma skin cancer. The use of
sunscreens starting early in life should be
stressed.
Basal
cell carcinoma: Choosing the best method of
treatment for a particular lesion
Hacker S.M.; Browder J.F.; Ramos-Caro F.A.
Dermatology/Cutaneous Surgery Div., Department of
Medicine, Florida University Coll. of Medicine, PO
Box 100277,Gainesville, FL 32610-0277 United
States
Postgraduate Medicine (United States) 1993, 93/8
(101-111)
Basal cell carcinoma is the most common type of
malignant tumor in the United States. The five
types of basal cell carcinoma (noduloulcerative,
pigmented, morpheaform, and superficial basal cell
carcinoma, and premalignant fibroepithelioma) vary
in clinical presentation and behavior. Diagnosis
is made by skin biopsy. The size, type, and site
of a lesion and the age and sex of the patient
affect the choice of treatment. Electrodesiccation
and curettage, cryosurgery, surgical excision,
Mohs' surgery, and radiation therapy are
available. Knowledge of these therapies and of
when they should and should not be used is
important in proper management of basal cell
carcinoma.
International poster parade: Sight
bites from the 18th World Congress of Dermatology
New York City June 12 to 18, 1992
Shelley E.D.; Shelley W.B.
Department of Medicine, Medical College of Ohio,
PO Box 10008,Toledo, OH 43699-0008 United
States
Cutis (United States) 1992, 50/3 (217-220)
Most of what we learn comes from reading, not
from listening. Thus, for us, the poster
presentation is ideal. It allows us to escape from
the confinement of the lecture hall and from the
constraint of having to listen to the obvious, the
repetitious, the uninteresting, and the
irrelevant. Come with us and scan those posters
that caught our roving clinical eye as we viewed a
thousand poster 'lectures.'
Sun-related skin
diseases
Prawer S.E.
Assoc. Skin Care Specialists, 7205 University Ave
NE,Fridley, MN 55432-3133 United States
Postgraduate Medicine (United States) 1991, 89/8
(51-54+59-61+64-66)
Severe photoaging of the skin, which may be
caused by exposure to both natural and artificial
ultraviolet light, ultimately results in actinic
keratoses and cancer. Cancers are common on the
head, neck, arms, and hands. Because of the
potential for metastasis, squamous cell carcinomas
generally require surgical excision and histologic
examination. Although metastasis is rare with
basal cell carcinoma, neglected lesions around the
eyes, nose, or ears can invade bone, nerves, and
cartilage and may cause death. Avoidance of sun,
physical protection, and regular use of sunscreens
are recommended.
Photocarcinogenesis is retarded by a
partly photodegraded solution of para-aminobenzoic
acid
Flindt-Hansen H.; Thune P.; Nielsen C.J.
Department of Dermatology, Ullevaal Hospital,
N-0407 Oslo 4 Norway
Photodermatology (Denmark) 1989, 6/6
(263-267)
A solution of para-aminobenzoic acid (PABA) was
exposed to ultraviolet (UV) radiation emitted from
a Philips TL 40 W/12 sunlamp and the degree of
photodegradation following an exposure of 27
J/cmsup 2 was estimated to be approximately 40%.
The formation of the photoproducts was confirmed
by mass spectroscopy and UV spectroscopy. The
solution was painted on the backs of hairless
light-pigmented mice prior to daily UV irradiation
by the above sunlamp, and this procedure was
continued for 30 weeks. The preirradiated solution
of PABA significantly retarded the tumor induction
time and reduced significantly the number of
squamous cell carcinomas compared with
non-protected controls. This tumor-retarding
ability did not differ significantly from the
effect achieved then using nonirradiated PABA.
[Use of
photoprotective measures in relation to actual
exposure to solar rays]
Kozarev J
Med Pregl (Yugoslavia) Nov-Dec 1998, 51 (11-12)
p555-8
OBJECTIVE: There is evidence that in spite of
worldwide campaigns against excessive sun
exposure, children as well as adults still spend
long periods in the sun. The purpose of this study
was to evaluate sun exposure in a group of doctors
of different specialties and to compare their
knowledge about sun protection methods with
regular use of sun protection products.
METHODS: 51 doctors of different specialties,
volunteers, mean age 40.78, filled out
questionnaires with 21 multiple choice questions
about their skin type, sun exposure habits, sun
protection habits and questions about meaning of
the Sun Protection Factor.
RESULTS: Thirty-three percent of our study
participants spent more than two peak ultraviolet
hours outdoors every day, and additional 33.33%
are sun exposed for longer than 5 hours,
regularly. Only 39% of them utilized sunscreens.
Majority of sunscreen users utilized less than 100
ml of commercial sunscreen products which is an
inadequate amount for full body protection per
year. Majority of study participants did not
believe that sunscreens could prevent skin cancer,
but 57% of them believed that these compounds can
slow the process of skin aging . Meaning of the
term Sun Protection Factor is not familiar to
84.3% study participants. The two most common
reasons for not using sunscreens are time
consuming application and high cost.
CONCLUSION: Results of the presented study
confirm our statement that there is bad
understanding of a need for sun protection which
is in correlation with deficient application of
sun protective measures. It should be stressed out
that our study participants lack well formed sun
protection habits.
A
review of sunscreen safety and
efficacy.
Gasparro FP; Mitchnick M; Nash JF
Department of Dermatology & Cutaneous
Biology, Thomas Jefferson University,
Philadelphia, PA 19107, USA
francis.gasparro@mail.tju.edu
Photochem Photobiol (United States) Sep 1998, 68
(3) p243-56
The use of sunscreen products has been
advocated by many health care practitioners as a
means to reduce skin damage produced by
ultraviolet radiation (UVR) from sunlight. There
is a need to better understand the efficacy and
safety of sunscreen products given this ongoing
campaign encouraging their use. The approach used
to establish sunscreen efficacy, sun protection
factor (SPF), is a useful assessment of primarily
UVB (290-320 nm) filters. The SPF test, however,
does not adequately assess the complete
photoprotective profile of sunscreens specifically
against long wavelength UVAI (340-400 nm).
Moreover, to date, there is no singular, agreed
upon method for evaluating UVA efficacy despite
the immediate and seemingly urgent consumer need
to develop sunscreen products that provide
broad-spectrum UVB and UVA photoprotection. With
regard to the safety of UVB and UVA filters, the
current list of commonly used organic and
inorganic sunscreens has favorable toxicological
profiles based on acute, subchronic and chronic
animal or human studies. Further, in most studies,
sunscreens have been shown to prevent the damaging
effects of UVR exposure. Thus, based on this
review of currently available data, it is
concluded that sunscreen ingredients or products
do not pose a human health concern. Further, the
regular use of appropriate broad-spectrum
sunscreen products could have a significant and
favorable impact on public health as part of an
overall strategy to reduce UVR exposure. (147
Refs.)
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