分子分型对乳腺癌新辅助化疗后肿瘤退缩模式的影响

  目的  探讨乳腺癌新辅助化疗（neoadjuvant chemotherapy，NAC）后不同分子分型的乳腺原发病灶退缩模式。  方法  选取2008年7月至2017年10月山东大学附属山东省肿瘤医院收治的108例ⅡA~ⅢC期乳腺浸润性导管癌行新辅助化疗后手术患者的临床病理资料，手术标本制作次连续病理大切片，电子显微镜下勾画残余肿瘤范围，三维重建残余肿瘤，评价新辅助化疗后原发肿瘤临床病理退缩模式。  结果  108例患者新辅助化疗后向心性退缩（concentric shrinkage mode，CSM）与非向心性退缩（nonconcentric shrinkage mode，NCSM）中Luminal A型分别占47.4%（9/19）与52.6%（10/19），Luminal B HER-2阴性型、HER-2阳性型分别占53.6%（15/28）、72.7%（16/22）与46.4%（13/28）、27.3%（6/22），HER-2阳性型分别占84.6%（11/13）与15.4%（2/13），三阴性乳腺癌分别占80.8%（21/26）与19.2%（5/26）。  结论  Luminal B HER-2阳性型、HER-2阳性型及三阴性乳腺癌的原发肿瘤更易出现CSM，Luminal A型、Luminal B型HER-2阴性型的原发肿瘤临床病理退缩模式无显著性差异。分子分型可用于预测乳腺癌新辅助化疗后原发肿瘤的临床病理退缩模式，有助于选择新辅助化疗后适合保乳治疗的患者、降低局部复发率。 

Effect of molecular typing on breast tumor regression mode after neoadjuvant chemotherapy

  Objective  To investigate the differences in shrinkage mode of the primary tumor in patients with different molecular subtypes of breast cancer after neoadjuvant chemotherapy (NAC).  Methods  One hundred and eight patients with breast invasive ductal carcinoma received NAC from July 2008 to October 2017 at Shandong Cancer Hospital Affiliated to Shandong University. After surgery, the surgical specimens were used to generate large continuous pathological sections. Using electron microscopy, the residual tumor range was delineated, residual tumor was reconstructed in three dimensions, and pathological regression pattern of the primary tumor after NAC was evaluated.  Result  Luminal A type accounted for 47.4% (9/19) and 52.6% (10/19) of patients with concentric shrinkage mode (CSM) and non-CSM (NCSM) after NAC, respectively. Luminal B human epidermal growth factor receptor 2 (HER2)+ type and HER2+ type accounted for 53.6% (15/28) and 72.7% (16/22) and 46.4% (13/28) and 27.3% (6/22) of patients, respectively. HER2+type accounted for 84.6% (11/13) and 15.4% (2/13) of patients, respectively, and triple-negative breast cancer accounted for 80.8% (21/26) and 19.2% (5/26) of patients, respectively.  Conclusions  Luminal B HER2+, HER2+, and basal-like types were more likely to have concentric shrinkage mode. The luminal A and luminal B HER2- type had no significant difference in primary tumor regression patterns. Molecular typing is helpful for predicting the regression mode of primary tumors after NAC in patients with breast cancer, which facifitates the selection of appropriate patients for breast-conserving therapy and redution of the local recurrence rate after NAC.