目的 探讨左右半结直肠癌（CRC）在临床病理特征和基因表达层面的异质性，为个体化治疗提供依据。 方法 回顾性分析广西医科大学第四附属医院在2020年7月至2023年8月收治的186例左右半CRC患者的临床资料、二代测序（NGS）技术检测结果及治疗方案，依照解剖学部位，分为左半CRC（134例）和右半CRC（52例），采用SPSS24.0软件进行临床病理特征数据分析，采用Kaplan-Meier法绘制左右半CRC患者的生存曲线，总生存期比较采用Log-rank检验。比较左半结直肠癌与右半结直肠癌患者临床病理特征、二代测序技术检测结果及预后差异。 结果 （1）在临床病理特征方面：左、右半CRC患者在性别、是否远处转移、ECOG评分、TNM分期和CEA、CA19-9中差异无统计学意义（P > 0.05），但在年龄上差异有统计学意义（P < 0.05）。左半CRC男性患者占比更多，而右半CRC患者在年龄上更大。（2）在基因突变特征方面：NRAS、BRAF及APC基因突变频率在左右半CRC中差异无统计学意义（P > 0.05）；然而，右半CRC患者中PIK3CA、SMAD4基因突变频率及MSI状态显著高于左半CRC患者且差异有统计学意义（P < 0.05），而左半CRC患者的TP53基因突变频率高于右半CRC且差异有统计学意义（P < 0.05）。（3）在预后分析中，对患者进行3年随访两组患者的总体生存率（OS）无显著差异。 结论 左右半结直肠癌在临床病理特征不尽相同尤其是基因表达方面存在显著差异，提示应在临床诊治中采用差异化策略，以实现个体化、精准化治疗。这一差异化管理策略有助于更全面地理解疾病的异质性，并为精准医学在结直肠癌中的应用提供理论支持和实践指导。

Objective To investigate the heterogeneity between left? and right?sided colorectal cancer （CRC） in terms of clinical pathological features and gene expression， thereby providing a foundation for personalized treatment. Methods A retrospective analysis was conducted on the clinical data， next?generation sequencing （NGS） results， and treatment plans of 186 CRC patients treated at the forth hospital affiliated of guangxi medical university from July 2020 to August 2023. Patients were categorized into left?sided CRC （n = 134） and right?sided CRC （n = 52） based on tumor location. Clinical and pathological characteristics were analyzed using SPSS 24.0 software， and Kaplan?Meier survival curves were generated to compare overall survival （OS） between groups using the Log?rank test. Additionally， this study compared the clinical and pathological features， NGS?based gene mutation profiles， and prognostic differences between left? and right?sided CRC patients. Results In the clinical and pathological characteristics， no significant differences were observed between left? and right?sided CRC patients regarding gender， distant metastasis， ECOG performance status， TNM stage， or levels of carcinoembryonic antigen （CEA） and carbohydrate antigen 19?9 （CA19?9） （P > 0.05）. However， there were significant differences in age （P < 0.05）. In terms of gene mutation characteristics， the mutation frequencies of NRAS， BRAF， and APC genes did not differ significantly between left? and right?sided CRC patients （P > 0.05）. However， right?sided CRC patients exhibited significantly higher mutation frequencies of PIK3CA and SMAD4 genes， as well as a higher prevalence of microsatellite instability （MSI）， compared to left?sided CRC patients （P < 0.05）. Conversely， left?sided CRC patients had significantly higher TP53 mutation frequencies than right?sided CRC patients （P < 0.05）. In prognostic analysis， after a three?year follow?up， no significant difference in OS was observed between the two groups. Conclusions Significant disparities are observed in the clinical pathological features and gene expression profiles between left? and right?sided CRC. These findings indicate that distinct approaches should be adopted in clinical diagnosis and treatment to facilitate personalized and precise care.