[Analysis of prognosis and related factors in oldest-old patients with left-side or right-side colon cancer after hemicolectomy].

Objective: This study aimed to explore the difference of prognosis in oldest-old colon cancer patients between the left-side and right-side hemicolectomy. Methods: A total of 238 oldest-old (≥75 years old) colon cancer patients who received surgical treatment in Gastrointestinal Surgery Department of Beijing Hospital from December 2010 to December 2020 were retrospectively collected. They were divided into right-side hemicolectomy (RCC) group (130 cases) and left-side hemicolectomy (LCC) group (108 cases) by surgical methods. The difference in postoperative short-term complications and long-term prognosis was compared between the two groups, and the related factors of postoperative death was analyzed using multivariate Cox regression model. Results: The age of 238 oldest-old patients with colon cancer ranged from 75 to 93 years old (80.5±3.7). There were 128 males and 110 females. The ages of patients in the LCC group and RCC group were (80.4±3.7) and (80.6±3.7) years old (P=0.699), respectively. There was no significant difference in gender, body mass index (BMI) and co-existing chronic diseases between two groups (P>0.05). The proportion of the duration of surgery exceeding 170 min in the LCC group was significantly higher than that in the RCC group (56.5% vs 43.1%, P=0.039). The incidence of postoperative short-term complications in RCC group was slightly higher than LCC group (P>0.05), and there was no significant difference in overall survival (OS), tumor-specific survival (CSS) and disease-free survival (DFS) between two groups. However, the two groups had different prognostic risk factors, pathological Ⅳ stage (HR=28.970,95%CI:1.768-474.813,P=0.018), intraoperative bleeding (HR=2.297,95%CI:1.351-3.907,P=0.002) and cancer nodules (HR=2.044,95%CI:1.047-3.989,P=0.036) were independent prognostic risk factors in LCC group. Underweight (HR=0.428,95%CI:0.192-0.955,P=0.038), overweight(HR=0.316,95%CI:0.125-0.800,P=0.015),obesity (HR=0.211,95%CI:0.067-0.658,P=0.007), lymph node metastasis (HR=2.682,95%CI:1.497-4.807,P=0.001), tumor nodule (HR=2.507,95%CI:1.301-4.831,P=0.027) and postoperative length of stay of 9 days (HR=1.829,95%CI:1.070-3.128,P=0.006) were independent risk factors for poor prognosis in RCC group. Conclusions: The duration of surgery of oldest-old colon cancer patients in the LCC group was longer than that in the RCC group. However, there was no significant difference in the incidence of postoperative complications between the two groups. High pathological stage, more intraoperative bleeding and cancer nodules were independent prognostic risk factors in the LCC group. Abnormal BMI, lymph node metastasis, cancer nodules and postoperative length of stay were independent risk factors for poor prognosis in the RCC group.