Sebaceous carcinoma of the breast

Abstract

We report on a rare distinctive variant of infiltrating ductal carcinoma characterized by sebaceous differentiation of tumor cells. The neoplasm was identified in a lumpectomy specimen from a 45-year-old woman with extensive metastatic disease. In addition to conventional in situ and invasive ductal components, approximately half of the tumor cells exhibited a phenotype resembling tumors of the sebaceous skin appendage with coarsely vacuolated cytoplasm and peripherally displaced nuclei. The sebaceous moiety was also present in the distant metastatic deposits. There was no evidence of mucin production by tumor cells. Ultrastructurally, empty-appearing non-membrane bound vacuoles attested to the sebaceous cells' lipid content. The immunoprofile of the lesion included positivity for cytokeratin and epithelial membrane antigen. Vimentin, S100 protein and carcinoembryonic antigen were not expressed. Most tumor cell nuclei reacted with antibodies to oestrogen and progesterone receptors but failed to show overexpression of the HER2/neu protein. The MIB-1 labeling index averaged 16%. At variance with sebaceous breast carcinomas on record, the present case is notable for its prolonged clinical course.

Original paper Sebaceous carcinoma of the breast: report of four cases and review of the literature

“…Regarding the potential therapeutic targets in mammary SC, altogether six cases (including three present cases) were ER and PR-positive [3,5,6] and one case was ER-negative/PR-positive [4]. Three cases were hormone receptors-negative, including one of our cases [8,9].…”

“…Two reported cases showed metastasis in one regional lymph node [6,8]; three cases had negative lymph nodes [3][4][5]. Follow-up is available in three cases only: one patient was alive with no evidence of disease 24 months after the operation [8]; the second patient had no evidence of disease after ten months [3]; the third patient had skin and bone metastases 132 months after surgery [5]. Follow-up of our cases indicates that mammary SC might be a highgrade malignant neoplasm.…”

“…Sebaceous carcinoma is defined as a breast carcinoma with prominent sebaceous differentiation in at least 50% of cells and no evidence of origin from cutaneous adnexal sebaceous glands [12]. To the best of our knowledge, only ten cases of mammary SC are well documented in the English-language literature conforming to the above definition [1,[3][4][5][6][7][8][9]; these cases are summarized in Table IV. One of these cancers occurred in a male patient [3].…”

“…It has been described in 15 cases so far in the English-language literature, either as a minor or predominant component in a classical ductal carcinoma or as a pure line of differentiation [1][2][3][4][5][6][7][8][9][10][11]. According to the current WHO classification, primary sebaceous carcinoma of the breast must show sebaceous differentiation in at least 50% of cells and have no evidence of origin from the cutaneous adnexa [12].…”

Mammary Carcinoma with Sebaceous Differentiation in a Dog

“…1 Both skin appendages and the secretory and ductal apparatus of the mammary gland share a common embryonic ectodermal anlagen. 13 The origin and pathway of the sebaceous metaplasia in mammary carcinomas remain unclear. It is suggested that there is an association between sebaceous gland metaplasia and squamous metaplasia.…”