原发性乳腺癌分子分型与新辅助化疗疗效及预后的相关性

Objective To explore the relationship of molecular subtypes with the responses and outcome of primary breast cancer patients treated with neoadjuvant chemotherapy. Methods We included 204 patients with primary breast cancer treated with neoadjuvant chemotherapy in He'nan Tumor Hospital in this retrospective study. The patients were classified into 4 subtypes: Luminal A, Luminal B, HER2 positive and triple-negative. The predictive role of molecular subtype in the response and outcome of breast cancer patients treated with neoadjuvant chemotherapy were analyzed. Results Among all 204 patients, 40(19.6%) patients were Luminal A subtype, 46(22.5%) were Luminal B subtype, 36 (17.6%) were HER2 positive subtype and 82 (40.2%) were triple-negative subtype. The pCR rates of HER2 positive(22.2%) and triplenegative(24.4%) subtypes were higher than those of Luminal A(2.5%) and Luminal B(6.5%), with significant difference(P=0.03). Despite initial chemosensitivity, the patients with HER2 positive and triple-negative subtypes had worse disease-free survival(DFS)(P=0.001) and overall survival(OS)(P= 0.002) than those with Luminal subtypes in the whole population, and especially worse in patients with residual disease after neoadjuvant chemotherapy with decreased DFS(P<0.001) and OS(P<0.001). The 5-year DFS and OS of patients who achieved pathological complete response(pCR) were significantly higher than those of patients with residual disease after chemotherapy(P=0.002, P=0.012, respectively). Conclusion We have found that breast cancer patients with HER2 positive and triple-negative subtypes have higher sensitivity to neoadjuvant chemotherapy and with higher rates of pCR but worse prognosis than those with Luminal subtypes.