A Novel Case of Mammary-Type Myofibroblastoma With Sarcomatous Features

Autor: Laura J. Tafe, Konstantinos Linos, Alexander M. Strait, Kristen E. Muller
Rok vydání: 2020
Předmět:
Zdroj: International Journal of Surgical Pathology. 29:308-313
ISSN: 1940-2465
1066-8969
DOI: 10.1177/1066896920947465
Popis: Mammary-type myofibroblastoma (MFB) is a benign spindle cell tumor of the breast and soft tissue characterized by 13q14 alterations leading to loss of Rb-1 protein expression, a feature shared among spindle cell lipoma and cellular angiofibroma. In this article, we present a novel case of MFB arising in the left breast of a 70-year old man that microscopically showed an abrupt transition from classic MFB morphology to an area with cytologic atypia and mitotic activity, akin to sarcomatous transformation described in cellular angiofibromas. A thorough workup of the molecular underpinnings of both components using chromosomal microarray and next-generation sequencing platforms supported a clonal relationship. Nearly identical copy number changes, including a single copy loss of 13q14, were found in both components; in addition, the sarcomatous component harbored biallelic TP53 alterations. It is important for pathologists to recognize that sarcomatous features can occur in mammary-type MFB to arrive at the correct diagnosis.
Databáze: OpenAIRE