Only 50–70% of elderly colon cancer patients could complete the recommended 6 months of postoperative chemotherapy. It is unknown whether a shorter duration of postoperative capecitabine-alone chemotherapy would compromise survival. We thus conducted this study to analyze the association between postoperative chemotherapy duration of a capecitabine-alone regimen and cancer-specific survival (CSS) and disease-free survival (DFS) of surgery-treated elderly colon cancer patients. We performed a retrospective cohort study of surgically treated stage III and high-risk stage II colon cancer patients aged ≥ 70 treated at two medical centers. Cox proportional hazard regression models were utilized to calculate crude and adjusted hazard ratios (HRs). The nonlinear relationship between postoperative chemotherapy duration and survival was analyzed through restricted cubic spline regression analysis, and the threshold effect was calculated by the two-piecewise Cox proportional hazard model. A total of 1217 surgery-treated colon cancer patients between August 1, 2013, and September 1, 2019, were reviewed, and 257 stage III and high-risk stage II patients aged ≥ 70 were enrolled. Postoperative chemotherapy with capecitabine was administered to 114 patients, and 143 patients only received surgery. As the duration of chemotherapy increased by 1 week, the risk of cancer-specific death was reduced by 11% (HR = 0.89, 95% confidence interval (CI) 0.82–0.96), and the risk of recurrence was reduced by 10% (HR = 0.90, 0.82–0.96). Nonlinearity exploration suggested a threshold effect of capecitabine duration on CSS in stage III disease. The HR for death was 0.79 (95% CI, 0.68–0.92) with duration ≤ 16 weeks and 1.34 (95% CI, 0.91–1.97) with duration > 16 weeks. The postoperative capecitabine duration was significantly associated with a decrease in death risk and recurrence risk in elderly colon cancer patients. However, the threshold effect of capecitabine duration on survival suggests that short-term chemotherapy may improve survival in elderly stage III colon cancer patients.

中文翻译：

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老年人结肠癌手术后卡培他滨方案持续时间的影响：一项回顾性队列研究

只有 50-70% 的老年结肠癌患者可以完成推荐的术后 6 个月化疗。目前尚不清楚术后较短的卡培他滨单药化疗时间是否会影响生存。因此，我们进行了这项研究，以分析单独卡培他滨方案的术后化疗持续时间与接受手术治疗的老年结肠癌患者的癌症特异性生存率 (CSS) 和无病生存率 (DFS) 之间的关联。我们对在两个医疗中心接受手术治疗的年龄≥70 岁的 III 期和高危 II 期结肠癌患者进行了一项回顾性队列研究。Cox 比例风险回归模型用于计算粗略和调整后的风险比 (HR)。通过限制三次样条回归分析分析术后化疗持续时间与生存率的非线性关系，并通过两分段Cox比例风险模型计算阈值效应。共回顾了2013年8月1日至2019年9月1日期间接受手术治疗的结肠癌患者1217例，纳入257例≥70岁的III期和高危II期患者。114 名患者接受卡培他滨术后化疗，143 名患者仅接受手术治疗。随着化疗持续时间增加1周，癌症特异性死亡风险降低11%（HR=0.89，95%可信区间（CI）0.82-0.96），复发风险降低10%（ HR = 0.90, 0.82–0.96)。非线性探索表明卡培他滨持续时间对 III 期疾病 CSS 的阈值效应。死亡的 HR 为 0.79（95% CI，0.68-0.92），持续时间 ≤ 16 周，1.34（95% CI，0.91-1.97），持续时间 > 16 周。术后卡培他滨持续时间与老年结肠癌患者死亡风险和复发风险的降低显着相关。然而，卡培他滨持续时间对生存率的阈值效应表明短期化疗可能会提高老年 III 期结肠癌患者的生存率。术后卡培他滨持续时间与老年结肠癌患者死亡风险和复发风险的降低显着相关。然而，卡培他滨持续时间对生存率的阈值效应表明短期化疗可能会提高老年 III 期结肠癌患者的生存率。术后卡培他滨持续时间与老年结肠癌患者死亡风险和复发风险的降低显着相关。然而，卡培他滨持续时间对生存率的阈值效应表明短期化疗可能会提高老年 III 期结肠癌患者的生存率。