Cancer Vaccines and Immunotherapy
Tracking Your Progress
Monthly Blood Tests. A range of blood tests and other diagnostic procedures can be used to monitor the effectiveness of cancer immunotherapy. Results from these tests provide information required to assess the effectiveness of this new treatment modality.
The following tests are essential for monitoring the effectiveness of immunotherapy.
- Tumor antigen profile: determining the antigens (abnormal proteins) produced by each tumor is important in assessing the use of cancer vaccines or other forms of immunotherapy as a treatment choice. Tumor antigen profile should also be monitored during immunotherapy, as the tumor can develop variations that stop the display of these antigens as a means of escaping detection.
- Immune cell function: the function of lymphocytes is monitored during cancer immunotherapy by a variety of techniques. These include proliferation assays to assess their ability to expand in response to activation, and cell-kill (cytotoxic) assays to assess the ability of CD8 lymphocytes to kill tumor cells (Clay TM et al 2001; Keilholz U et al 2002b; Lyerly HK 2003).
- PSA: prostate-specific antigen can be detected in blood samples from prostate cancer patients and has been established as a reliable marker for disease progression or patient response to therapy (Coetzee LJ et al 1996; Kiper A et al 2005). Prostate cancer patients treated with cancer vaccines in clinical studies showed reductions in their PSA levels (Noguchi M et al 2004b; Noguchi M et al 2004a).
- CEA: monitoring of serum levels of carcinoembryonic antigen is recommended for colorectal cancer patients as a marker for disease progression or response to treatment (Sunga AY et al 2005).
- Angiogenesis markers: angiogenesis is the process of forming new blood vessels, which is essential for tumors to spread to other parts of the body. Increased levels of the angiogenic factor vascular endothelial growth factor (VEGF) in the blood of cancer patients serves as a robust indicator of disease progression and can be used to monitor response to treatment with cancer immunotherapy (Bonfanti A et al 2000; Brostjan C et al 2003; Poon RT et al 2001). Circulating endothelial cells, detectable in the blood of cancer patients, are increased and have also been established as another indicator of disease progression (Beerepoot LV et al 2004; Mancuso P et al 2003).
- Growth factors: serum levels of the growth factors pleiotrophin (PTN) and fibroblast growth factor-2 (FGF-2) are increased in prostate cancer patients and can be used as a marker for disease progression or response to therapy (Aigner A et al 2003).
- Immunosuppressive agents: levels of tumor-produced immunosuppressive agents (for example, interleukin-10 (IL-10) (Sarris AH et al 1999) and transforming growth factor-beta (TGF-ß) (Junker U et al 1996)) can be detected in patients’ serum and used to check for disease progression or response to treatment.
- X-rays and scans: can be used to monitor the response or progression of disease during cancer immunotherapy.
- Physical examination: regular physical examinations can detect changes in body mass and enlarged lymph nodes that may be signs of disease progression (Sunga AY et al 2005).
For More Information
Cancer immunotherapy patients may wish to read the following chapters and design a program that addresses the full range of their cancer problems:
The National Cancer Institute Clinical Trials Database lists and describes ongoing clinical trials at different locations throughout the US. This can be accessed at the website http://cancertrials.nci.nih.gov/ or by calling the Cancer Information Service at 1-800-4-CANCER.
The American Cancer Society, 1-800-ACS-2345.