三阴性大汗腺癌的新辅助化疗反应：大汗腺形态学、雄激素受体与免疫表型比较

CONTEXT. —: Apocrine differentiation and androgen receptor (AR) positivity represent a specific subset of triple-negative breast cancer (TNBC) and are often considered potential prognostic or predictive factors. OBJECTIVE. —: To evaluate the response of TNBC to neoadjuvant chemotherapy (NAC) and to assess the impact of apocrine morphology, AR status, Ki-67 labeling index (Ki-67LI), and tumor-infiltrating lymphocytes (TILs).

DESIGN. —: A total of 232 TNBC patients who underwent NAC followed by surgical resection in a single institute were analyzed. The study evaluated apocrine morphology and AR and Ki-67LI expression via immunohistochemistry from pre-NAC biopsy samples.

Additionally, pre-NAC intratumoral TILs and stromal TILs (sTILs) were quantified from biopsies using a deep learning model. The response to NAC after surgery was assessed based on residual cancer burden. RESULTS. &#x2014;: Both apocrine morphology and high AR expression correlated with lower Ki-67LI (P < . 001 for both). Apocrine morphology was associated with lower postoperative pathologic complete response (pCR) rates after NAC (P = . 02), but the difference in TILs between TNBC cases with and without apocrine morphology was not statistically significant (P = . 09 for sTILs).

In contrast, AR expression did not significantly affect pCR (P = . 13). Pre-NAC TILs strongly correlated with postoperative pCR in TNBCs without apocrine morphology (P < . 001 for sTILs), whereas TNBC with apocrine morphology demonstrated an indeterminate trend (P = . 82 for sTILs). CONCLUSIONS.

&#x2014;: Although TIL counts did not vary significantly based on apocrine morphology, apocrine morphology itself was a more reliable predictor of NAC response than AR expression. Consequently, although apocrine morphology is a rare subtype of TNBC, its identification is clinically important.