CHICAGOThe clinical rationale for breast-conserving surgery has been unequivocally established by prospective, randomized clinical trials that show no difference in survival between this form of surgery and mastectomy. In many parts of the country, however, less than 50% of women with early-stage breast cancer are having breast-conserving surgery.
These low rates are not because women have clear medical contraindications to the surgery but because some physicians do not understand the goal of breast-conserving surgery, Monica Morrow, MD, professor of surgery, Northwestern University Medical School, said at the annual scientific meeting of the American College of Surgeons.
The objective of breast-conserving therapy is to surgically excise the bulk of the tumor (with radiation therapy used to eradicate residual localized cancer) and to preserve a cosmetically acceptable breast. It is not indicated if there is a high risk of recurrence of disease in the breast, complications, or an unsatisfactory cosmetic result. There are, she said, four absolute contraindications to breast-conserving surgery:
- Pregnancy, although such surgery may be done during the third trimester with irradiation following delivery.
- Two or more primary tumors in separate quadrants of the breast or diffuse microcalcifications.
- Previous irradiation of the breast.
- Persistent positive tissue margins after surgery.
A history of collagen vascular disease, such as scleroderma or active lupus erythematosus, is a relative contraindi-cation, she said.
Many commonly held contraindica-tions are now obsolete, Dr. Morrow noted. In the past, breast-conserving surgery was not performed on tumors in the retroareolar area because of the potentially poor cosmetic outcome. However, the nipple/areola complex can be left behind for better cosmesis without increasing the risk of local failure. Only those rare tumors that actually adhere to the posterior surface of the nipple require surgical excision of the nipple.
An extensive intraductal component was associated with a high risk of local failure of breast-conserving therapy in the past when tissue margins were not routinely examined microscopically. Today, she said, as long as the tissue margin is negative, the risk for local failure is no different whether or not an extensive intraductal component is present.
Many false contraindications to breast-conserving therapy are due to the misunderstanding that this treatment is appropriate only for patients with early-stage, favorable cancers who are node negative, Dr. Morrow said. As a result, tumor size, axillary node involvement, and histologic grade and type have been considered valid reasons for not performing breast-conserving surgery. However, these factors predict the risk of distant failure, not local recurrence.
Poor prognostic features may indicate the need for systemic therapy, but they are not indications for mastectomy, she said.