Efficacy of neoadjuvant chemotherapy in locally advanced colon cancer

The generally accepted strategy for treating locally advanced colon cancer is radical surgery involving resection of the colonic portion with the tumor and lymphadenectomy followed by adjuvant chemotherapy. The issue of increasing the metabolic activity of micrometastases and tumor seeding after removal of the primary tumor remains relevant. Objective. To study the efficacy and safety of neoadjuvant chemotherapy (NACHT) in patients with locally advanced resectable colon cancer. Material and methods. The medical records of 90 patients at the Botkin Hospital from January 1, 2022 to January 1, 2024 with colon adenocarcinoma. with stage cT3 or higher and/or involvement of regional lymph nodes (cN+) regardless of the T value, with the absence of MSI (microsatellite instability), without distant metastasis and with chemotherapy in the XELOX, FOLFOX and FOLFOXIRI regimens were retrospectively analyzed. Results. A full course of NACHT was completed by 83 patients (92.2%) without progression and/or grade III–IV complications. Progression was observed in three patients (3.3%). Surgical treatment was performed in all patients, R0 resections were achieved in 100% of cases. Adjuvant chemotherapy was not received by 29 patients (32.2%). Toxicity during NACHT was observed in 34 cases (37.7%). The incidence of grade III–IV complications was 5 (5.1%). Complete therapeutic pathomorphosis was observed in 3 patients (3.3%), partial tumor response in 39 (43.3%). The median follow-up was 23.1 months, the incidence of progression was 10 months (11.1%). Local relapse was observed in 3 patients (3%), distant metastases — in 7 patients (8%). The 2-year overall and relapse-free survival rates were 94 and 92.8%, respectively. Conclusion. NACNT is safe and effective for patients with colon cancer: tolerability is satisfactory, the risk of progression is minimal, and the incidence of postoperative complications is comparable with the results of the world literature. Prospective comparative studies are needed to further study this topic.