ISPO

Published in Cancer Detection and Prevention 2000; 24(Supplement 1).

Prophylactic medical/surgical intervention

RHM Verheijen MD PhD

University Hospital Vrije University, Amsterdam, The Netherlands, r.verheijen@azvu.nl

AIMS. Primary prevention of cancer is aimed at preventing cancer to arise using means that have little disadvantages. METHODS. Primary prevention of cancer putatively includes adjusting one's life style, discarding noxeous agents, correcting adverse gene expression, modification of the immunologic environment and also reducing the susceptibility of tissue or organs for oncogenic changes by either medical treatment or surgical removal of tissue at risk. These latter two approaches are currently the most direct and feasible ways to prevent cancer. They also allow easy evaluation of its effectiveness. Medical prevention meanly refers to interaction with (hormone) receptors, not surprisingly as these are the cellular ports of communication, although this only holds for so-called hormone related cancers. Prophylactic surgery is a drastic and for some an unexceptable form of prevention, often requiring reconstructive surgery. None of these approaches, however, can as yet totally prevent cancer. Medical and surgical prevention should be offered to persons with an increased risk of cancer, not to the general population. Specifically persons carrying a predisposing gene mutation for colon cancer, breast cancer and ovarian cancer are amenable for this type of prevention. It is well appreciated that the level of anxiety very much influences the decision regarding prophylactic operation. Before embarking on a preventive treatment strategy we advise our clients to first discuss their choice carefully with a counseller. Routine oophorectomy, as routine appendicectomy, should not be performed during surgery for other reasons for the sole reason of "being there anyway". RESULTS. Medical treatment can at best reduce the risk of cancer by influencing receptor status. Even surgical removal of tissue has intrinsically the risk of being incomplete (e.g. colectomy or oophorectomy) with a residual risk. SIDE EFFECTS. Most of this preventive treatment carries a high rate of side effects. It may interfere with normal hormonal or physiological function, e.g. after oophorectomy or colectomy respectively. Surgery may lead to disfigurement, e.g. after mastectomy, which cannot always completely be hidden by plastic surgery. Immediate reconstruction should be advocated. The psychological impact of especially preventive surgery may be great and often does not outweigh the advantages. BENEFIT. Treatment with Tamoxifen has proven to reduce the risk of breast cancer. New selective estrogen receptor modifiers (SERMs) are now being tested to pair improved efficacy to fewer side effects. Colectomy has proven to be very effective in preventing various forms of hereditary colon cancer and is now less traumatic thanks to new endoscopic techniques. Mastectomy is extremely effective to prevent breast cancer but is unpopular with women, who often reside with mammographic screening that can detect breast cancer at a curable stage. Oophorectomy gives little visible scarring but has a direct effect on hormonal function, which can nowadays easily and safely be counteracted with replacement therapy even in those at high risk for breast cancer. CONCLUSION: Medical and surgical prevention should only be offered in selective cases where there is proven increased risk of cancer.

KEY WORDS: prevention, high risk groups.

For more information, contact r.verheijen@azvu.nl

Paper presented at the International Symposium on Impact of Biotechnology on Cancer Diagnostic & Prognostic Indicators; Geneva, Switzerland; October 28 - 31, 2000; in the section on anticancer strategies.

http://www.cancerprev.org/Journal/Issues/24/101/401/3349