Background and Aims

This study aimed to assess the long-term survival of patients with T1 colorectal cancer (CRC) after local or surgical resection considering the type and number of risk factors for lymph node metastasis.

Methods

This study included patients with high-risk T1 CRC who underwent therapeutic resection at the National Cancer Center, Korea between January 2001 and December 2014. Risk factors included positive resection margin, high-grade histology, deep submucosal invasion, vascular invasion, budding, and no background adenoma (BGA). We statistically divided the population into favorable or unfavorable subpopulations. The favorable subpopulation included the following 5 combinations of risk factors: positive margin only or unconditional for margin status, deep submucosal invasion only, budding only, no BGA only, and budding + no BGA. We analyzed the survival rate according to the resection type (local or surgical) in the total cohort and in each subpopulation.

Results

Eighty-one and 466 patients underwent local and surgical resections, respectively. The distant recurrence-free survival (DRFS) and overall survival (OS) rates were significantly high in the surgical group (hazard ratio [HR], .20; 95% confidence interval [CI], .06-.61; P = .0045 and HR, .41; 95% CI, .25-.70; P = .0010, respectively). In the favorable subpopulation, both DRFS and OS rates were not significantly different between the surgical and local groups (HR, .26; 95% CI, .02-4.19; P = .3431 and HR, .58; 95% CI, .27-1.23; P = .1534, respectively).

Conclusions

Intensive surveillance without additional surgery may be another option in selected cases after of high-risk T1 CRC endoscopic resection.

中文翻译：

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高危 T1 期结直肠癌生存的亚群分析：手术与仅内镜下切除术

背景和目标

本研究旨在考虑淋巴结转移危险因素的类型和数量，评估局部或手术切除后 T1 期结直肠癌 (CRC) 患者的长期生存率。

方法

本研究纳入了 2001 年 1 月至 2014 年 12 月期间在韩国国家癌症中心接受治疗性切除术的高危 T1 CRC 患者。风险因素包括切缘阳性、高级别组织学、深层粘膜下浸润、血管侵犯、出芽和无背景腺瘤 (BGA)。我们在统计上将人口分为有利或不利的亚群。有利的亚群包括以下 5 种风险因素组合：仅切缘阳性或无条件切缘状态、仅深层粘膜下浸润、仅出芽、仅无 BGA 以及出芽 + 无 BGA。我们根据整个队列和每个亚群的切除类型（局部或手术）分析了存活率。

结果

分别有 81 名和 466 名患者接受了局部切除和手术切除。手术组的无远处复发生存率 (DRFS) 和总生存率 (OS) 显着较高（风险比 [HR]，0.20；95% 置信区间 [CI]，0.06-0.61；P  = . 0045 和 HR，0.41；95% CI，0.25-0.70；P  = 0.0010）。在有利的亚群中，DRFS 和 OS 率在手术组和局部组之间没有显着差异（HR，0.26；95% CI，0.02-4.19；P  = 0.3431 和 HR，0.58；95% CI，. 27-1.23；P  = .1534）。

结论

在高危 T1 CRC 内镜切除术后，无需额外手术的强化监测可能是选定病例的另一种选择。