Cancer principles & practice of oncology, 7th edition. DeVita Jr. VT; Hellman S; Rosenberg SA, eds. Philadelphia, PA: Lippincott Williams & Wilkins, 2004 Dec; :945-986
Pancreatic cancer (PC) is the fifth leading cause of cancer death in the United States, With 28,000 to 30,300 newly diagnosed cases (ductal adenocarcinoma being the most common form) per year. Approximately an equal number of deaths occur annually from PC. The incidence rate for PC is approximately nine new cases per 100,000 people, with the peak incidence the seventh and eighth decades of life and an average age of 60 to 65 years at diagnosis. The incidence rate is slightly higher in men than in women (relative risk, 1.35) and 30% to 40% higher in African American men. Survival in patients with untreated PC is poor. For all stages combined, the I-year survival rate is 19% and the 5-year survival is 4%. The majority (80%) of PCs are metastatic at the time of diagnosis. Surgical resection (when margin negative, node negative) offers the best possibility for cure, with 5- year survival approaching 40% when performed at specialized major medical institutions. In the United States, incidence rates of PC increased threefold between 1920 and 1978, an increase that has also been observed in other developed countries. Rates for men and for women have modestly declined since 1978 and appear to have stabilized at the current rates. A portion of the increased incidence may have been attributable to more accurate disease diagnosis and less disease misclassificauon. Additionally, improved surveillance may account for a small portion of the increased incidence. A positive relationship exists between certain environmental exposures and cases of PC, including personal cigarette smoking environmental tobacco smoke (ETS), and chemical exposures. Cigarette smoking in the United States and in other countries increased greatly in the first half of the twentieth century. In fact, 40% of adult Amencans were smokers m 1965. Increased cigarette smoking likely accounts for a large portion of the increased incidence of PC. By 1990, the prevalence of smoking among Americans had decreased to 25%, with modest declines again noted in 1999. Because of the long latency period before diagnosis, it remains to be seen if this will translate into lower PC incidence rates in the future.