Pleomorphic carcinoma of the breast: clinicopathological analysis of 26 cases of an unusual high-grade phenotype of ductal carcinoma

Aims: Pleomorphic carcinoma is a poorly described entity whose phenotype is not well recognized as within the morphological spectrum of breast carcino ma. The purpose of this report is to describe the clinicopathological featu res of this tumour, and to promote its recognition as an unusual high-grade morphological variant of mammary ductal carcinoma. Methods and results: Histological slides of breast carcinomas (N = 64) code d between 1978 and 1995 as having pleomorphic or anaplastic features were r eviewed. Pleomorphic carcinoma (N = 26) was diagnosed when greater than or equal to 50% of the tumour manifested a pleomorphic cell population (> sixf old variation in nuclear size). Tumours of lobular origin were excluded. Al l neoplasms occurred in women with a mean age of 53 years. Patients underwe nt biopsy and/or mastectomy (n = 24) or lumpectomy (n = 2). The tumours' me an size was 54 mm. All were high-grade neoplasms. The pleomorphic cell popu lation comprised 50-100% of the tumour; 31% had a prominent spindled morpho logy. Fifty-eight per cent of the tumours were initially misclassified by r eferring pathologists as sarcomas or carcinomas, possibly metastatic. Adjac ent DCIS or a transition to classic ductal carcinoma was present in 73%. Fi ve (19%) patients were stage I and three (12%) had stage IV disease. Axilla ry dissections yielded greater than or equal to 3 (mean 7.2) positive lymph nodes in 52%. Most (68%) tumours were aneuploid; a high S-phase (> 10%) wa s present in 63%. All neoplasms were ER negative and all but one were PR ne gative. p53 expression was present in 71%; none expressed bcl-2. c-erbB-2 w as detected in four (19%) node-positive and in 0 (0%) node-negative cases ( P = 0.01). Of 16 patients with follow-up, 6 (38%) were disease-free (mean, 74 months), four (25%) alive with disease (mean, 33 months) and six (38%) d ead of disease at a mean of 22 months. Conclusions: Pleomorphic carcinoma is a prognostically unfavourable lesion and represents the extreme end of the morphological spectrum of grade III i nfiltrating ductal carcinoma.