Prophylactic Surgery in Hereditary Breast/Ovarian Cancer Syndrome
Prophylactic Surgery in Hereditary Breast/Ovarian Cancer Syndrome
Drs. Levine and Gemignani have
composed an excellent comprehensive
review of the issues
surrounding prophylactic surgery
in patients at high risk for breast and
ovarian cancer. Their article focuses
on the role of BRCA1/2 mutations in
the risk of developing hereditary breast
and ovarian cancer and the data supporting
risk reduction in mutation carriers
undergoing prophylactic surgery.
Approximately 10% of ovarian cancer
and 5% of breast cancer cases are
due to an inherited predisposition, with
the majority due to mutations in the
BRCA1 and BRCA2 genes. For mutation
carriers, the authors have estimated
the lifetime risk of developing
breast cancer to range from 35% to
75%, and the risk of ovarian cancer,
from 20% to 40%. When considering
prophylactic surgery, the elevated risk
of cancer in these patients must be
balanced against several factors, such
as the availability of effective cancer
screening techniques, the cost and
morbidity of surgical prophylaxis, the
effectiveness of such prophylaxis, and
the available alternatives to surgery.
The case for prophylactic oophorectomy seems more clear. Laparoscopic oophorectomy may be performed on an outpatient basis in the majority of women, with low surgical morbidity and acceptable financial cost. Data from Rebbeck et al clearly demonstrate a significant reduction in the risk of developing ovarian or primary peritoneal cancer following prophylactic oophorectomy. Among 259 women with germ-line BRCA1 and BRCA2 mutations who underwent prophylactic surgery, 6 (2.3%) were diagnosed with occult ovarian cancer at the time of surgery and 2 (0.8%) developed primary peritoneal cancer, compared to 58 cases (19.9%) of ovarian cancer among 292 matched controls. Although the use of oral contraceptives is under investigation as a means to mitigate ovarian cancer risk, current data do not support as great a reduction in risk as that achieved with prophylactic oophorectomy. Promising, intensive screening techniques have yet to be proven effective in reducing mortality from ovarian cancer in high-risk women, and many women may not adhere to surveillance recommendations. Botkin et al recently showed that among mutation carriers, only 26% obtained an ultrasound in the first year and 11% in the second year after mutation testing. CA-125 testing was only used by 32% and 37% in the first and second year after testing, respectively. Similarly, Lerman et al reported that among mutation carriers, only 21% underwent CA-125 testing, and 15% underwent transvaginal ultrasound in the year following testing. In contrast, women in the Botkin et al study appeared to demonstrate a preference for prophylactic oophorectomy over screening, and 46% of all mutation carriers and 78% of those age 40 or older underwent the procedure. Meijers-Heijboer found similar results, with 49% of women requesting the surgery. Others have demonstrated a high level of satisfaction with the procedure, with a concomitant reduction in anxiety. Although the incidence of mutationassociated ovarian cancer is lower than that of breast cancer, the absence of reliable screening methods to detect early tumors combined with the high mortality of late-stage disease make prophylactic surgery a reasonable option for high-risk women. Prophylactic Mastectomy
Recommendations for prophylactic mastectomy are more problematic. Although studies have clearly demonstrated a marked reduction in the risk of breast cancer,[6,7] there is an inherent irony in recommending bilateral mastectomy for healthy women who are merely at risk for cancer, when those who actually develop the disease may be treated with breastconserving therapy. The use of prophylactic mastectomy varies in the reported literature from 0% to 35% of mutation carriers. Multiple factors make prophylactic mastectomy an unattractive option for many women. Aside from significant issues regarding body image and sexuality, women may prefer other options to ameliorate cancer risk. Intensive screening typically involves annual mammography beginning at age 25 combined with clinical and self-breast examination; the use of magnetic resonance imaging as a screening tool is currently under investigation. These options appear to be acceptable to patients and are used by a high percentage of mutation carriers. Botkin et al demonstrated that 71% of women obtained a mammogram within 2 years post-mutation testing. Over 80% adhered to recommendations for self-examination and clinical examination. However, this enthusiasm for surveillance must be tempered by the realization that screening is imperfect and may be less sensitive in both BRCA1 and BRCA2 mutation carriers, and in women under age 40. Safe, effective chemoprevention for breast cancer is another active area of investigation. The Breast Cancer Prevention Trial demonstrated that tamoxifen reduced the risk of invasive cancer by 49% among women at elevated risk. However, among the 288 women who developed invasive cancer, only 19 BRCA1 and BRCA2 mutation carriers were identified, making it difficult to base firm recommendations for mutation carriers on the available data, especially given the concern that the majority of BRCA1 mutation-associated cancers do not express estrogen receptors. The Study of Tamoxifen and Raloxifene (STAR) trial, in which patients at elevated risk of breast cancer by Gail criteria are randomized to either daily tamoxifen or raloxifene (Evista), is currently accruing patients to examine study end points of invasive and noninvasive breast cancer, cardiovascular disease, endometrial cancer, bone fracture, and thromboembolic events. Conclusions
Recommendations regarding surgical prophylaxis for patients with BRCA1/2 mutations need to be individualized. The clear reduction in ovarian cancer risk, weighed with the lack of proven effective screening techniques, and the generally tolerable side effects of early estrogen deprivation provide a strong argument for prophylactic oophorectomy. The decision to undergo prophylactic mastectomy may be more difficult for patients. Given the distinct reduction in cancer risk, mastectomy may be preferable to many patients. However, for others, intensive screening, chemoprophylaxis, and prophylactic oophorectomy, which has also has been shown to decrease breast cancer risk,[1,10,11] may be realistic alternatives.
2. Botkin JR, Smith KR, Croyle RT, et al: Genetic testing for a BRCA1 mutation: Prophylactic surgery and screening behavior in women 2 years post testing. Am J Med Genet 118A:201-209, 2003.
3. Lerman C, Hughes C, Croyle RT, et al: Prophylactic surgery decisions and surveillance practices one year following BRCA1/2 testing. Prev Med 31:75-80, 2000.
4. Meijers-Heijboer H, Brekelmans CT, Menke- Pluymers M, et al: Use of genetic testing and prophylactic mastectomy and oophorectomy in women with breast or ovarian cancer from families with a BRCA1 or BRCA2 mutation. J Clin Oncol 21:1675-1681, 2003.
5. Tiller K, Meiser B, Butow P, et al: Psychological impact of prophylactic oophorectomy in women at increased risk of developing ovarian cancer: a prospective study. Gynecol Oncol 86:212-219, 2002.
6. Hartmann LC, Schaid DJ, Woods JE, et al: Efficacy of bilateral prophylactic mastectomy in women with a family history of breast cancer. N Engl J Med 340:77-84, 1999.
7. Meijers-Heijboer H, van Geel B, van Putten WL, et al: Breast cancer after prophylactic bilateral mastectomy in women with a BRCA1 or BRCA2 mutation. N Engl J Med 345:159-164, 2001.
8. Brekelmans CT, Seynaeve C, Bartels CC, et al: Effectiveness of breast cancer surveillance in BRCA1/2 gene mutation carriers and women with high familial risk. J Clin Oncol 19:924-930, 2001.
9. Fisher B, Costantino JP, Wickerham DL, et al: Tamoxifen for prevention of breast cancer: Report of the National Surgical Adjuvant Breast and Bowel Project P-1 Study. J Natl Cancer Inst 90:1371-1388, 1998.
10. Rebbeck TR, Levin AM, Eisen A, et al: Breast cancer risk after bilateral prophylactic oophorectomy in BRCA1 mutation carriers. J Natl Cancer Inst 91:1475-1479, 1999.
11. Kauff ND, Satagopan JM, Robson ME, et al: Risk-reducing salpingo-oophorectomy in women with a BRCA1 or BRCA2 mutation. N Engl J Med 346:1609-1615, 2002.