The old axiom "an ounce of prevention is worth a pound of cure" is being increasingly recognized in oncology. Cancer prevention can be divided into three categories: (I) primary prevention (i.e., pre­venting initial cancers in healthy individuals); (2) secondary pre­vention (i.e., preventing cancer in individuals with premalignant conditions); and (3) tertiary prevention (i.e., preventing second pri­mary cancers in patients cured of their initial disease

The administration of systemic or local therapies to prevent the development of cancer, called chemoprevention, is being ac­tively explored for several cancer types. In breast cancer. the NSABP Breast Cancer Prevention Trial demonstrated that tamox­ifen reduces the risk of breast cancer by one half and reduces the risk of estrogen-receptor-positive tumors by 69% in high-risk

patients, Therefore tamoxifen has been approved by the Food and Drug Administration (FDA) for breast cancer chemopreven­tion. Several other agents. including raloxifene and fenretinide, also show promise for breast cancer prevention and are under ac­tive investigation. Celecoxib has been shown to reduce polyp number and polyp burden in patients with familial adenomatous polyposis (FAP). leading to its approval by the FDA for these pa­tients. In head and neck cancer, 13-cis-retinoic acid was shown to both reverse oral leukoplakia and reduce second primary tu­mor development.Thus the chemoprevention trials completed so far have demonstrated success in primary, secondary. and ter­tiary prevention. Although the successes of these chemopreven­tion studies are impressive. much remains to be done over the next few years to improve patient selection and decrease therapy­ related toxic effects. It is important for surgeons to be aware of these preventive options since they are likely to be involved in.the diagnosis of premalignant and malignant conditions. and will be the ones to counsel patients about their chemopreventive options.

In selected scenarios, the risk of cancer is high enough to justify surgical prevention. These high-risk scenarios include hereditary cancer syndromes such as hereditary breast ovarian cancer syndrome­
. hereditary diffuse gastric cancer. multiple endocrine neo­plasia type 2, FAP, and HNPCC, as well as some nonhereditary sce­narios such as chronic ulcerative colitis. Most prophylactic surgeries are large ablative surgeries (e.g., bilateral risk-reducing mastectomy or total proctocolectomy). Therefore it is important that the patient be completely informed about potential surgical complications as well as long-term lifestyle consequences. Further. the conservative options of close surveillance and chemoprevention need to be­

discussed. the patient's cancer risk needs to be assessed accurately and implications for survival discussed. ultimately. the decision to proceed with surgical prevention should be individualized and made with caution

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