In a patient with locally advanced breast cancer receiving neoadjuvant chemotherapy, complete pathological response (pCR) is most strongly predictive of improved event-free and overall survival in which molecular subtype?
- A Luminal A (ER+/PR+/HER2−/low Ki-67)
- B Triple-negative breast cancer (ER−/PR−/HER2−) ✓
- C Luminal B HER2-positive
- D ER+ lobular carcinoma
Correct answer: B. Triple-negative breast cancer (ER−/PR−/HER2−)
Explanation
pCR after neoadjuvant chemotherapy has the strongest prognostic impact in triple-negative breast cancer (TNBC) and HER2-positive subtypes, where achieving pCR translates to significantly improved event-free and overall survival. Luminal A tumours have the lowest pCR rates with standard chemotherapy and their prognosis is primarily determined by endocrine responsiveness, making pCR a weaker surrogate. Luminal B HER2+ also benefits from pCR but the magnitude is not as dramatic as TNBC. ER+ lobular carcinoma is notably chemoresistant.
Reference: Bailey & Love's Short Practice of Surgery, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.