Possible Signs and Symptoms of Pancreatic Cancer
- Jaundice (yellowing of the skin and whites of the eyes) due to blockage of the bile duct or liver malfunction.
- A gnawing pain from the stomach to the back.
- Unexplained weight loss.
- Fatigue, weakness, dark urine, light stools, and anorexia.
Screening and Early Detection
One of the main reasons that pancreatic cancer has a poor survival rate is the inability to screen for and prevent this disease. Pancreatic cancer needs to be detected early (precancerous lesions or small pancreatic cancers) in order to improve the chance of survival. Unfortunately, premalignant lesions and early pancreatic cancers are asymptomatic and current screening strategies are ineffective and inefficient (Kim 2011).
Currently, there are no approved screening tests for pancreatic cancer. CA 19-9 is elevated in 70-90% of patients but it is not accurate enough for early detection (poor sensitivity), nor is carcinoembryonic antigen (CEA) (Kim 2004). Efforts are underway to identify biomarkers with a high level of accuracy that detect pancreatic cancer at an early stage, e.g. early mutations in K-ras, p53, and p16, but none are yet in routine clinical use (Bussom 2010).
Future screening tests might incorporate biomarkers in addition to endoscopic ultrasound (EUS), possibly contrast-enhanced (Stoita 2011), or non-contrast MRI with ultrasound, which is now used in Japan (Kuroki-Suzuki 2011). In the future, proteomic analysis of pancreatic fluid aspirate will be a novel method of pancreatic cancer detection (Cuoghi 2011).
Blood Tests: Serum tumor markers can be detected by a simple blood test and can be used in conjunction with diagnostic imaging tests for the diagnosis of pancreatic cancer and for monitoring progress after surgery. Tumor markers used include CA19-9, CEA, CA-50, CA72-4, and CA242 (Jiang 2004).
CA 19-9 (carbohydrate antigen 19-9) is the mainstay tumor marker and is ordered when pancreatic cancer is suspected, particularly if the patient shows signs of jaundice. CA 19-9 levels match the course of the disease following treatment (Lamerz 1999). A high preoperative CA19-9 level (>500-1000 IU/mL) implies more advanced disease that is not amenable to resection (Fogelman 2008). Additional diagnostic methods are required because this test is only 70 percent sensitive and 87 percent specific for pancreatic cancer.
The EUROPAC study is currently evaluating fasting blood glucose as a marker for early pancreatic cancer in sporadic cases (Stolzenberg-Solomon 2005) and molecular analysis of pancreatic juice (K-ras and p53 mutations, and p16 promoter methylation). Screening for recent onset diabetes could possibly lead to early diagnosis or reduce pancreatic cancer deaths (Lowenfels 2006).
An alkaline phosphatase blood level that is four to five times the upper limits of normal (and disproportionate to the bilirubin level) may occur from tumor obstruction of the bile duct.
Assessment of pancreatic function. In pancreatic cancer, abnormal digestion associated with inadequate pancreatic enzymes and function (insufficiency) can occur (Bruno 1995a). When pancreatic enzyme levels fall below 1 - 2 percent of normal, poor nutrient digestion and incorporation occur. Poor digestion can cause significant weight loss, nutritional deficiencies, and foul-smelling or greasy bowel movements. It is also associated with changes in gastrointestinal function, such as changes in acid-base balance, bile acid metabolism, stomach emptying, and motility of the intestines (Grant 1978).
Tests for pancreatic enzyme function include:
- Lipase, amylase, chymotrypsin levels and bicarbonate secretion (Ochi 1997; Bruno 1995b).
With enzyme supplementation, weight loss and biochemical indices of malnutrition can be greatly improved (Braga 1988).
Tests for pancreatic hormone function include:
- Insulin: Fasting blood sugar levels and an oral glucose tolerance test (OGTT) (Yamaguchi 2000).
- Measurement of hormone levels (insulin, glucagon, somatostatin, and pancreatic polypeptide) after a meal (Schusdziarra 1984).