Clinicopathological study of a dimorphic variant of breast carcinoma

Nozomi Ueno,Jun Ito,Masafumi Kurosumi,Keiichi Kubota,Yasuo Imai,Yuji Kozuka,Hajime Kuroda,Hiroyuki Kato

doi:10.1007/s12282-017-0804-x

Abstract

BackgroundDimorphic cells have abundant clear cytoplasm similar to myoepithelial cells, and the nuclei are identical to those in adjacent malignant columnar epithelial cells. A dimorphic variant of a breast carcinoma involves a neoplastic proliferation of epithelial cells including dimorphic cells.MethodsThe subjects were patients with primary breast carcinoma, who underwent surgical resection at the Hospital of Dokkyo Medical University between 2000 and 2016, and were reviewed and diagnosed with a dimorphic variant of breast carcinoma.ResultsDimorphic ICs typically showed a low-grade tumor and Hormonal receptor (HR) (estrogen and/or progesterone)+/HER2− subtype. Age, mean tumor size, status of nodal metastasis, stage and disease-free survival and overall survival did not differ between dimorphic and non-dimorphic ICs. The dimorphic cells were negative for p63 and cytokeratin 5/6 and 14 in most cases. In contrast, dimorphic cells were positive for HR, androgen receptor, and showed marked membrane-associated staining for E-cadherin and cytoplasmic staining for gross cystic disease fluid protein 15.ConclusionsThe morphological features of dimorphic cells may be confused with cells of other origins if the features of the dimorphic cells are not recognized. However, the typical morphological architecture of this carcinoma and expression of immunohistochemical markers support the diagnosis.

Highlights

Lefkowitz et al reported 20 cases of intraductal papillary carcinomas (IPCs) with cuboidal cells with abundant clear or faintly eosinophilic cytoplasm [1,2,3,4]
Lefkowitz et al suggested that the presence of these tumor cells might create a problem in the differential diagnosis of an IPC as they might be misinterpreted as myoepithelial cells
The subjects were cases of primary breast carcinoma that were surgically resected at the Hospital of Dokkyo Medical University (HDMU) between 2000 and 2016, and were reviewed for the histological presentation of dimorphic breast carcinoma

Summary

Introduction

Lefkowitz et al reported 20 cases of intraductal papillary carcinomas (IPCs) with cuboidal cells with abundant clear or faintly eosinophilic cytoplasm [1,2,3,4]. These cells were located mainly near the basement membrane singly, in small clusters, or in broad sheets. There are dimorphic cells in invasive breast carcinomas similar to DCIS. Dimorphic cells have abundant clear cytoplasm similar to myoepithelial cells, and the nuclei are identical to those in adjacent malignant columnar epithelial cells. Dimorphic cells were positive for HR, androgen receptor, and showed

Methods

Results

Conclusion