Is radical surgery for clinical stage I right-sided colon cancer relevant? A retrospective review

PURPOSE: Radical lymph node dissection for right-sided colon cancer is technically challenging. No clear guideline is available for surgical resection of clinical stage I right-sided colon cancer. This study was designed to review the pathologic stage of clinical stage I right-sided colon cancer and determine the relevant extent of surgical resection. METHODS: Patients were treated for clinical stage I right-sided colon cancers (cecal, ascending, hepatic flexure, and proximal transverse colon) between July 2006 and December 2014 at a tertiary teaching hospital. Open surgery was not included because laparoscopic surgery is an initial major procedure in the institution. RESULTS: During the study period, 80 patients diagnosed with clinical stage I right-sided colon cancer were classified into 2 groups according to the pathology: stage 0/I and II/III. Tumor sizes were larger in the stage II/III group (P = 0.003). The stage II/III group had higher rates of vascular (P = 0.023) and lymphatic invasion (P = 0.023) and lower rates of well differentiation (P = 0.022). During follow-up, 1 case of local and 4 cases of systemic recurrences were found. Multivariate analysis to confirm odds ratios affecting change from clinical stage I to pathological stage II/III showed that tumor size (P = 0.010) and the number of retrieved lymph nodes (P = 0.046) were risk factors. CONCLUSION: For right-sided colon cancer, even with clinical stage I included, radical lymph node dissection should be performed for exact staging with sufficient number of lymph nodes. This will help determine appropriate adjuvant treatment, especially in large tumor sizes.