The Circumferential Resection Margin Is a Prognostic Predictor in Colon Cancer

Abstract

Objective: This study aimed to investigate the potential value of circumferential resection margin (CRM) in colon cancer prognostics. Summary Background Data: CRM has been extensively studied as an important prognostic factor in rectal and esophageal cancer, but not in colon cancer. Methods: Data from 6,681 CRM-positive patients and 25,908 CRM-negative patients diagnosed with colon cancer in 2010–2015 were obtained from the Surveillance, Epidemiology, and End Results database. Statistical analysis methods utilized included the chi-square test, Kaplan-Meier estimates, Cox proportional, and X-tile software analyses. Results: After propensity score matching, CRM positivity was found to be negatively related with survival (P < 0.001). X-tile software identified 0 and 30 mm as optimal cutoff values ( P < 0.001) for prognosis, which was applicable only in stage II–IV patients. A 20 and 33% risk decrease were observed in patients with CRM between 0 and 30 mm [95% confidence interval (CI) = 0.76–0.84], and larger than 30 mm (95% CI = 0.62–0.71), respectively. Chemotherapy strongly benefited prognosis with a hazard ratio of 0.36 (95% CI = 0.34–0.38) for overall survival (OS). Patients with a CRM value of 0–30 mm seemed to benefit most from chemotherapy compared with other groups. CRM and number of regional lymph nodes are independent risk factors, and the latter is a good substitute for CRM in AJCC stage I patients. Conclusion: CRM positivity is a strong unfavorable survival indicator for colon cancer patients. A better outcome is expected with CRM values larger than 30 mm. This cutoff value only applied to stage II–IV patients. For stage I patients, number of regional lymph nodes is a good substitute to predict survival. Chemotherapy was another favorable prognostic factor, especially for patients with a CRM value between 0 and 30 mm.

Pathological Features and Prognostication in Colorectal Cancer

“…Amri et al initially confirmed the prognostic significance with CRM involvement in colon cancer in 2015, identifying it as an independent prognostic factor linked with reduced OS (HR 3.39 p < 0.001), reduced DFS (HR 2.03 p < 0.001), and higher rates of recurrence (HR 3.32 p < 0.001) [ 253 ]. These findings are confirmed in a large population study by Tang et al in 2020, which found that patients with a CRM value of 0–30 mm benefited most from chemotherapy [ 255 ]. Evidence on the optimal CRM in both rectal and colon cancer is inconsistent.…”

“…CRM positivity occurs in 7.3% to 25% of rectal cancers and 5.3% to 20.5% of colon cancers. It is associated with advanced stage, aggressive tumour grade, infiltrating tumour border, and lymphovascular and perineural invasion [ 253 , 255 ]. In rectal cancer, CRM positivity is a strong predictor of recurrence and reduced survival, independent of TNM staging [ 252 , 256 , 257 , 258 , 259 ].…”

“…The significance of CRM positivity is less studied in colon cancer, however recent evidence suggests that its poor prognostication in rectal cancer also applies to colon cancer [ 253 , 254 , 255 , 260 ]. Amri et al initially confirmed the prognostic significance with CRM involvement in colon cancer in 2015, identifying it as an independent prognostic factor linked with reduced OS (HR 3.39 p < 0.001), reduced DFS (HR 2.03 p < 0.001), and higher rates of recurrence (HR 3.32 p < 0.001) [ 253 ].…”

“…There was a survival benefit for the CRM 5.1–10-mm group compared to the 1.1–5-mm group, however this was not statistically significant [ 258 ]. In colon cancer, Tang et al found a margin >30 mm was associated with improved outcomes among CRM-negative patients [ 255 ].…”

Diagnosis of Nonperitonealized Colorectal Cancer with Computerized Tomography Image Features under Deep Learning

“…For the development and popularization of complete mesorectal excision (CME) surgery in China, the scope of surgical resection is more thorough than that of traditional radical surgery, significantly improving the surgery quality. On the contrary, the CRM of some deeply infiltrated cancer tissues may still be negatively affecting the correct evaluation of the CRM [ 9 ].…”