Sarcomatoid (metaplastic) carcinoma of the breast: The U.T. M.D. Anderson Cancer Center (MDACC) and SEER database experience

Abstract

614 Background: Sarcomatoid (metaplastic) carcinoma of the breast is a rare disease which contains overtly carcinomatous and sarcoma-like elements on light microscopy; its clinical behaviour is not well documented. Methods: To better define the clinical features of sarcomatoid breast carcinoma, MDACC records were searched for patients diagnosed from 1985–2002. We also searched the SEER database for patients with this disease registered between 1988 and 2001. Descriptive statistics were used to summarize patient characteristics. Results: From the MDACC records, we identified 100 sarcomatoid breast cancer patients. Their median follow-up was 55 months (range, 4–252).The median age at diagnosis was 48 years (range, 26–77), 76% had grade 3 disease, 66% had node-negative disease, and 57% had stage 2 disease. Six percent had ER-positive and 9% had PR-positive tumors. Of 26 patients with a known HER2/neu status, 24 were HER2/neu-negative. Of 94 patients with localized disease at diagnosis, all but 1 had surgery, 82% received adjuvant chemotherapy, and 54% radiotherapy. The median recurrence-free survival (RFS) of these patients was 74 months (range, 3 to 252), with a 52% RFS rate at 5 years. The median overall survival (OS) of these patients was not reached, with 64% alive at 5 years. Fifty percent of first recurrences were local. Median survival from the time recurrent disease was recognized was only 14 months (range, 1 to 50). The 5-year RFS was low and not statistically different between patients who did and did not receive adjuvant chemotherapy, although all 3 patients treated with an anthracycline/ifosfamide-based regimen did remain recurrence-free. The SEER database registered 213 cases of sarcomatoid breast cancer of a total of 281,382 breast cancers. Information from this database was remarkably consistent with our findings. Conclusions: Sarcomatoid (metaplastic) cancer of the breast is rare, usually receptor-negative, and often aggressive and treatment-refractory. The role of ifosfamide with standard chemotherapy should be explored. The biology of this disease needs to be better defined with the aid of gene array and other new technologies to develop targeted therapies. No significant financial relationships to disclose.