Should multicentric disease be an absolute contraindication to the use of breast-conserving therapy?

PURPOSE: Multicentric cancer is present in a large proportion of mastectomies performed as treatment of breast cancer; it has been considered a contraindication to breast conservation. METHODS AND MATERIALS: We reviewed the records of our patients with Stage I or II breast cancer treated with breast conserving surgery and radiation therapy over a 13-year period. Twenty-seven patients had two or more nodules of grossly visible cancer separated by histologically normal breast tissue. All patients had grossly negative margins of excision; however, four patients had microscopically positive margins. Nine patients had positive axillary nodes. All patients received radiation therapy to the breast postoperatively, with a median dose of 50.4 Gy in 28 fractions; 11 patients also received a boost dose of 6-20 Gy to the tumor bed. Eleven patients were given adjuvant chemotherapy and one patient was given adjuvant tamoxifen.
RESULTS: With a median follow-up of 53 months, only one patient has relapsed in the breast (3.7%); that patient relapsed in multiple distant sites at the same time. Three patients have died of disseminated disease; the actuarial survival and disease-free survival rates at 4 years are 89%.
CONCLUSION: Breast conservation may be considered for patients with multicentric breast cancer discovered at the time of histologic examination. For patients with multicentric disease detected prior to surgery, breast conserving therapy may be appropriate as long as: (1) all clinically and radiographically apparent abnormalities are removed, (2) clear margins of resection are achieved, and (3) there is no extensive intraductal component.