Metaplastic breast cancer: an all-round multidisciplinary consensus

Abstract

Metaplastic breast cancer (MpBC) is a rare and aggressive histologic subtype of breast cancer (BC) characterized by the presence of at least two cellular types, commonly epithelial and mesenchymal components. Despite growing evidence that MpBC is a unique entity, it has long been treated as a variant of nonspecial type (NST) BC. MpBC typically shows the phenotype of triple-negative breast cancer (TNBC), but compared to NST-TNBC, it is a relatively chemorefractory tumor associated with worse outcomes. Therefore, there is an urgent need to develop management guidelines specifically for MpBC to improve the prognosis of patients with early MpBC. This expert consensus aims to guide diagnosis and standardize clinical management of early MpBC among treating physicians. We provide guidance on the challenging radiological and pathological diagnosis of MpBC. Evidence on the involvement of genetic predisposition in the development of MpBC is also explored. We emphasize the importance of a multidisciplinary approach for the treatment of patients with early MpBC. The optimal surgery and radiotherapy approach is presented, as well as the opportunity offered by novel therapeutic approaches to increase treatment response in this chemoresistant subtype. Appropriate management of patients with MpBC is critical to reduce the high risk of local and distant recurrence that characterizes this disease. European

Case Report on Complete Response to Treatment of Metastatic Metaplastic Breast Cancer with Sacituzumab Govitecan

“…Although the ideal treatment for this disease in the early setting is still a subject of study, all available data agreed with the low response of MBC to neoadjuvant chemotherapy and with a pathological complete response (pCR) rate varying between 0% and 25% [12]. Due to the aggressiveness of the tumor and poor response to neoadjuvant treatment, oncological surgery should be considered as the first therapeutic option in localized diseases at risk for progression during treatment.…”

Ductal carcinoma in situ within a fibroadenoma: A case report and review of literature

“…Metaplastic breast cancer, on mammography, are commonly large masses of 4.2 cm, with high density and smooth, well-defined and spiculated margins. Microcalcifications are very rare within the mass; when this happens, they are more likely to be amorphous, fine pleomorphic, fine linear, and lastly coarse heterogeneous[ 30 , 31 ].…”

Reporte de caso: carcinoma metaplásico de mama con componente epitelial escamoso puro y mutación de PIK3CA

“…El carcinoma metaplásico de mama (CMM) corresponde a un subtipo raro, con una incidencia que representa solo del 0,2 al 5% de todos los tumores malignos (4,5). Se presenta con mayor frecuencia entre los 48 y 59 años de edad, y sus diferentes variantes son frecuentemente agresivas, resistentes a la quimioterapia y tienen una alta propensión a hacer metástasis especialmente a pulmón (6). Los CMM se presentan generalmente con ISSN: 2697-3391 Vol.…”