Background

Intensive surveillance of colon cancer by using the abdominopelvic computed tomography (AP-CT) is common in real world practice; however, it is still unclear whether high-frequency surveillance using AP-CT in patients with these risk factors is superior to that in the low-frequency surveillance.

Patients and Methods

We retrospectively reviewed 1803 patients with stage II-III colon cancer receiving curative surgery between January 1, 2005 to December 31, 2015. We evaluated the average scan-to-scan intervals of postoperative AP-CT testing and assigned patients with an interval of 5 to 8 and 9 to 13 months to the high-frequency (HF) and low-frequency (LF) groups, respectively. The cutoff value of preoperative and postoperative CEA levels was 5 ng/mL. We also applied propensity score matching (PSM) and inverse probability of treatment weighting to adjust clinicopathologic differences between the 2 groups.

Results

We matched 1:1 for each surveillance group yielding a cohort of 776 matched patients. After PSM, Baseline demographics were overall well balanced between 2 groups. Stage III (OR, 2.00; 95% Confidence interval [CI], 1.21-3.30) and postoperative CEA elevation (OR, 2.30; 95% CI, 1.08-4.92) were independent risk factors of recurrence in multivariate analyses. Patient in the HF group had more surgery plus chemo- or radiotherapy as postrecurrence treatment than patient in the LF group (46.2% vs. 23.1%, P = .017). This trend was retained after PSM, although it is not significant (44.4% vs. 23.1%, P = .060). However, survival outcomes of high-frequency AP-CT surveillance were not superior to those of low-frequency surveillance in all subgroups, including stage III (HR 0.99, 95% CI 0.40-2.47) and postoperative CEA elevation (HR 1.36, 95% CI 0.45-4.11).

Conclusion

High-frequency AP-CT testing is associated with a higher proportion of surgery plus chemo- or radiotherapy as postrecurrence treatment, without improvement in 5-year overall survival.

中文翻译：

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高频与低频腹部盆腔计算机断层扫描随访测试对 II 期或 III 期结肠癌患者总体生存率的影响

背景

在现实世界的实践中，使用腹盆腔计算机断层扫描 (AP-CT) 对结肠癌进行强化监测很常见；然而，目前尚不清楚对具有这些危险因素的患者使用 AP-CT 进行高频监测是否优于低频监测。

患者和方法

我们回顾性审查了2005年1月1日至2015年12月31日期间接受根治性手术的1803名II-III期结肠癌患者。我们评估了术后AP-CT检测的平均扫描间隔，并以间隔5次分配患者高频组 (HF) 和低频组 (LF) 分别为 8 个月和 9 至 13 个月。术前和术后CEA水平的临界值为5 ng/mL。我们还应用倾向评分匹配（PSM）和治疗加权的逆概率来调整两组之间的临床病理差异。

结果

我们对每个监测组进行 1:1 匹配，产生 776 名匹配患者的队列。PSM 后，两组之间的基线人口统计数据总体平衡。在多变量分析中，III期（OR，2.00；95%置信区间[CI]，1.21-3.30）和术后CEA升高（OR，2.30；95% CI，1.08-4.92）是复发的独立危险因素。HF 组患者比 LF 组患者接受更多手术加化疗或放疗作为复发后治疗（46.2% vs. 23.1%，P  = .017）。PSM 后保留了这一趋势，尽管并不显着（44.4% vs. 23.1%，P  = .060）。然而，在所有亚组中，高频 AP-CT 监测的生存结果并不优于低频监测，包括 III 期（HR 0.99，95% CI 0.40-2.47）和术后 CEA 升高（HR 1.36，95%） CI 0.45-4.11）。

结论

高频 AP-CT 检测与较高比例的手术加化疗或放疗作为复发后治疗相关，但 5 年总生存率没有改善。