Association of the number of positive lymph nodes, lymph node ratio, and log odds of positive lymph nodes with survival prognosis in N2 stage colon cancer.

e15508 Background: Colon cancer is the third most common cancer globally and a leading cause of cancer death. Accurate prognosis prediction, crucial for reducing mortality, is influenced by lymph node metastasis. This study evaluates the prognostic significance of positive lymph nodes (pLNs), lymph node ratio (LNR), and log odds of positive lymph nodes (LODDS) in pN2 stage colon cancer. Methods: A retrospective analysis was conducted on patients from our center, enrolled between March 2013 and December 2018. The study examined the relationship between pLNs, LNR and LODDS with clinical variables. Disease-free survival (DFS) and overall survival (OS) were examined using Kaplan-Meier survival analyses and Cox regression proportional hazards analyses. Results: The database analyzed 217 treatment episodes. Univariate Cox regression analyses showed significant impacts of pathological type, pT status, pLNs, LNR, and LODDS on DFS, with pathological type, pLNs, LNR, and LODDS significantly influencing OS. Multivariate Cox regression identified pN2b, CA199 positive, signet ring cell carcinoma and pT4 independently associated with worse DFS, and pN2b independently associated with worse OS. Univariate Cox regression analyses found that 6 months of postoperative adjuvant chemotherapy significantly influenced OS in pN2a colon cancer, but no significant differences in pN2b colon cancer. Conclusions: This study has demonstrated that pLNs is associated with survival prognosis in pN2 stage colon cancer than LNR and LODDS. Furthermore, the currently available postoperative chemotherapy regimens are insufficient for patients with pN2 colon cancer.