Comparative Effectiveness of an mTOR‐Based Systemic Therapy Regimen in Advanced Metaplastic and Nonmetaplastic Triple‐Negative Breast Cancer

摘要

Background.Triple‐negative breast cancer (TNBC) is a heterogeneous disease with subtypes having different “targetable” molecular aberrations. Metaplastic breast cancers (MpBCs) are typically TNBCs and commonly have alterations in the PI3K/Akt/mTOR pathway. We previously reported efficacy for an mTOR‐based chemotherapy regimen in MpBC. To determine if tumor subtype influences prognosis, we compared treatment outcomes of patients with MpBC with those of patients with nonmetaplastic TNBC receiving an mTOR‐based systemic therapy regimen.