Department of Colorectal Surgery, Tianjin Union Medical Center, Tianjin, 300121, China.
Tianjin Institute of Coloproctology, Tianjin, China.
BMC Cancer. 2022 Nov 10;22(1):1156. doi: 10.1186/s12885-022-10266-3.
We evaluated the prognostic role of deficient mismatch repair (dMMR) systems in stage II and stage III colon cancer patients during different postoperative periods. We also assessed whether patients aged ≥75 could benefit from chemotherapy.
This retrospective study was conducted across three medical centers in China. Kaplan-Meier survival methods and Cox proportional hazards models were used to evaluate the differences in overall survival (OS) and disease-free survival (DFS) rates. Propensity score matching was performed to reduce imbalances in the baseline characteristics of the patients. Landmark analysis was performed to evaluate the role of dMMR during different postoperative periods.
The median follow-up time for all patients was 45.0 months (25-75 IQR: 38.0-82.5). There was no significant OS (p = 0.350) or DFS (p = 0.752) benefit associated with dMMR for stage II and III patients during the first postoperative year. However, significant OS (p < 0.001) and DFS (p < 0.001) benefits were observed from the second postoperative year until the end of follow-up. These differences remained after propensity score matching. Moreover, chemotherapy produced no OS (HR = 0.761, 95% CI: 0.43-1.34, p = 0.341) or DFS (HR = 0.98, 95% CI: 0.51-1.88, p = 0.961) benefit for patients aged ≥75 years.
The benefits of dMMR in stage III patients were observed from the second postoperative year until the end of follow-up. However, the prognosis of patients with dMMR is not different from that of patients with proficient mismatch repair (pMMR) during the first postoperative year. In addition, elderly patients aged ≥75 years obtained no significant survival benefits from postoperative chemotherapy.
我们评估了在不同术后时期，Ⅱ期和Ⅲ期结肠癌患者中错配修复缺陷（dMMR）系统的预后作用。我们还评估了年龄≥75 岁的患者是否能从化疗中获益。
这是一项在中国三家医疗中心进行的回顾性研究。使用 Kaplan-Meier 生存方法和 Cox 比例风险模型评估总生存期（OS）和无病生存期（DFS）率的差异。采用倾向评分匹配法减少患者基线特征的不平衡。采用 landmark 分析评估 dMMR 在不同术后时期的作用。
所有患者的中位随访时间为 45.0 个月（25-75 IQR：38.0-82.5）。对于Ⅱ期和Ⅲ期患者，在术后第一年，dMMR 与 OS（p=0.350）或 DFS（p=0.752）无显著获益。然而，从术后第二年开始直至随访结束，dMMR 与显著的 OS（p<0.001）和 DFS（p<0.001）获益相关。在进行倾向评分匹配后，这些差异仍然存在。此外，化疗对年龄≥75 岁的患者在 OS（HR=0.761，95%CI：0.43-1.34，p=0.341）或 DFS（HR=0.98，95%CI：0.51-1.88，p=0.961）方面没有获益。
Ⅲ期患者的 dMMR 获益从术后第二年持续到随访结束。然而，在术后第一年，dMMR 患者的预后与 proficient mismatch repair（pMMR）患者无差异。此外，年龄≥75 岁的老年患者从术后化疗中未获得显著的生存获益。
