早发型结直肠癌的临床病理及分子病理学特征

Clinical and molecular pathological features of early-onset colorectal cancer

目的 通过分析早发型结直肠癌(CRC)的临床及分子病理学特征,探讨其潜在发病机制及生物学行为。方法 回顾江苏省人民医院/南京医科大学第一附属医院病理学部2018—2020年CRC手术样本,整理相关的临床,分子病理学及随访资料。结果 在1243例手术样本中,早发型CRC(≤50岁)共计180例(14%):女性73例,男性107例;右半结肠42例,左半结肠136例;57例肿瘤为低分化,122例为中高分化;肿瘤平均大小为(4.37±2.01)cm;组织学腺癌143例,黏液腺癌或含黏液成分38例;微卫星高度不稳定(MSI-H)22例,微卫星稳定或低度不稳定(Non-MSI-H)158例。检测到KRAS突变型79例;NRAS突变型4例;BRAF突变型6例。相对于非早发型CRC,早发型肿瘤的分化更差,MSI-H比例更高(P<0.05)。Kaplan-Meier曲线显示早发型与非早发型CRC 3年总生存率无显著差异(P>0.05)。COX比例风险模型显示发病年龄(≤50岁)对CRC患者生存无显著影响(P>0.05)。结论 早发型CRC具有特殊的临床病理及分子病理学特征,提示这部分肿瘤具有独特的潜在发病机制和治疗方式。针对早发型病例发病率的逐年增加,建议采取相应措施的实施,有效提升高风险人群的早筛参与度和病变检出率。

Objective To analyze the clinical, pathological and molecular features of early-onset colorectal cancer(EOCRC), and to investigate the potential pathogenic mechanism and biologic behavior. Methods There were a retrospective collection of 1243 surgical colorectal cancer(CRC) cases between 2108 and 2020, with clinical, molecular pathological and survival data. Results Among 1243 CRC cases, EOCRC samples were 180 cases in total: 73 female cases and 107 male cases;42 cases raised from right-sided and 136 from left-sided;57 cases showed poorly differentiated and 122 cases well and moderately differentiated;the mean size of tumor was 4.37±2.01 cm;143 cases were adenocarcinoma and 38 cases with mucinous components;22 cases with MSI-H and 158 cases with non-MSI-H;79 cases presented with KARS mutations;4 cases with NRAS mutations and 6 cases with BRAF mutations. Compared to non-EOCRC, EOCRC showed poor differentiation and higher proportion of MSI-H(P<0.05). Kaplan-Meier analysis showed there was no significant difference between early-onset CRC and mortality(P>0.05). Cox proportional risk model showed onset age(≤50) was no significant effect on survival of CRC patients(P<0.05). Conclusion Compared to non-early-onset CRC, EOCRC has unique clinical-pathological and molecular-pathological features, suggesting that these tumors harbor the special pathogenic mechanism, and demand a corresponding specific treatment. As increasing incidence of EOCRC yearly, it is recommended that corresponding measures should be implemented to improve early screening participation and detection rate among high risk population.