Mesenchymal tumours of the breast and their mimics: a review with approach to diagnosis.
Mesenchymal tumours of the breast comprise a broad spectrum of entities that frequently pose diagnostic challenges to surgical pathologists. Metaplastic carcinoma and phyllodes tumour are site-specific mimics that account for the majority of tumours in the breast with a sarcomatoid appearance. Although uncommon, mammary tumours with fibroblastic, adipocytic or vascular differentiation may be encountered, spanning the spectrum from benign to malignant. Tumours with histiocytoid morphology are potential traps due to bland cytomorphology and resemblance to reactive processes. This comprehensive review provides a diagnostic approach to specific challenging mesenchymal tumours of the breast and their mimics, with a discussion on the salient morphological, immunohistochemical and molecular features that allow accurate diagnosis and will help the pathologist avoid potential pitfalls.
Douglass Hanly Moir Pathology, Macquarie Park, NSW, Australia.
Alison L
AL
Cheah
Cleveland Clinic, Pathology and Laboratory Medicine Institute, Cleveland, OH, USA.
Steven D
SD
Billings
Cleveland Clinic, Pathology and Laboratory Medicine Institute, Cleveland, OH, USA. Electronic address: rowej@ccf.org.
J Jordi
JJ
Rowe
D001943:Breast Neoplasms / Q000175:diagnosis* / Q000473:pathology; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008637:Mesenchymoma / Q000175:diagnosis* / Q000473:pathology
Breast; adipocytic tumours; fibroblastic tumours; histiocytoid morphology; mesenchymal breast tumours; metaplastic carcinoma; phyllodes tumour; sarcoma; soft tissue; spindle cell; vascular tumours