CMDT 2013
Cancer Patricia A. Cornett, MD Tiffany O. Dea, PharmD
The major features of this chapter are the clinical aspects of cancer, including etiology and prevention; staging; diagnosis and treatment of common cancers; and recognition and management of complications from cancer. Additional information may be obtained from the National Cancer Institute (NCI) website at www.cancer.gov/cancer topics, the American Society of Clinical Oncology website at www. asco.org, and the National Comprehensive Cancer Network (NCCN) website at www.nccn.org. The NCCN website provides detailed, evidence-based recommendations for management of specific cancers as well as guidelines for cancer screening and for supportive care. General reviews in oncology can be obtained from Medscape Hematology/ Oncology (www.medscape.com).
``Etiology Cancer is the second most common cause of death in the United States. In 2011 an estimated 1,596,670 cases of cancer were diagnosed, and 571,950 persons died as a result of cancer. Based on cancer rates determined in 2003–2005, more than 40% of people born today will have cancer diagnosed at some point in their lifetime. Table 39–1 lists the 10 leading cancer types in men and women by site. However, the incidence of cancer in both men and women is decreasing. In 2008, the American Cancer Society, NCI, and the Centers for Disease Control and Prevention reported that the incidence of all cancers for both sexes decreased 0.8% per year from 1999 through 2005. As the incidence of cancer is decreasing, the survival rate is increasing. In 2010, using information from the Surveillance Epidemiology and End Results (SEER) database, the NCI reported a survival rate of 68% for individuals in whom cancer was diagnosed between 1999 and 2006 compared to 50% for those in whom cancer was diagnosed between 1975 and 1977. Reductions in cancer incidence and mortality reflect a successful implementation of a broad strategy of prevention, detection, and treatment.
``Modifiable Risk Factors Tobacco is the most common preventable cause of cancer death; it is estimated that at least 30% of all cancer deaths
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in the United States are directly linked to tobacco. A total of 171,000 cancer deaths in the United States and 1.42 million cancer deaths worldwide can be directly attributed to tobacco abuse. Clear evidence links at least 15 cancers to tobacco use. The most dramatic link is with lung cancer, the most common non-dermatologic malignancy; 87% of lung cancer cases occur in smokers. Any strategy for cancer control must include the goal of markedly reducing if not eliminating tobacco use. Strategies for tobacco control should involve a focus on the individual as well as society as a whole. Tobacco cessation directed toward the individual should start with the clinician providing counseling. Simple, concise advice from a clinician can yield cessation rates of 10–20%. Additive strategies include more intensive counseling; nicotine replacement therapy with patches, gum, or lozenges; and prescription medication with bupropion or varenicline. Perhaps a more intriguing phenomenon, with potential for significant impact on cessation rates, is the influence of social contact behavior on an individual smoker’s abstinence decision. For instance, analysis of the Framingham Heart Study demonstrated that smoking cessation by a spouse resulted in a 67% decrease in the subject’s likelihood of continuing to smoke, and smoking cessation by a friend resulted in a 36% decrease in the subject’s likelihood of smoking. On a societal level, many initiatives have been put into place to actively discourage tobacco use. State or local laws regulating tobacco use in restaurants, the workplace, and other public places have resulted in declines in tobacco use. Countermarketing with aggressive anti-tobacco advertisements has also contributed to tobacco cessation and abstinence. The key recipients of these messages are children; 80% of smokers will start by age 18. Preventing the start of addiction in this vulnerable population should be a top priority (see Chapter 1). There are encouraging signs of success with tobacco control. The prevalence of smoking for United States adults based on the 2011 National Health Interview Survey is 19.4%, which is a remarkable reduction from the 1955 peak of 57% for males and the 1965 peak of 34% for females but still falls short of the Healthy People 2010 goal of < 12%. See Chapter 1 for additional material on smoking cessation techniques.