Short-term and long-term outcomes of intracorporeal anastomosis in laparoscopic segmental left colectomy for splenic flexure cancer - a multicenter retrospective cohort study of 342 cases

Introduction: While intracorporeal anastomosis (IA) has been widely used in totally laparoscopic right colectomy, its application in laparoscopic segmental left colectomy for splenic flexure cancer remains underexplored, particularly in large-scale studies with long-term outcomes. This research aims to assess the technical feasibility and oncological efficacy of IA in treating colonic splenic flexure carcinoma, drawing insights from both short-term and long-term outcomes of a retrospective cohort. Materials and methods: A retrospective analysis was conducted on 342 patients diagnosed with colonic splenic flexure carcinoma in three Chinese medical centers. These patients underwent laparoscopic segmental left colectomy between December 2014 and December 2019 across three medical institutions. Comprehensive data encompassing demographics, disease features, pathological characteristics, operative details, and both short-term and long-term outcomes were gathered and scrutinized. Using propensity scores, each patient from the IA cohort was paired with a counterpart from the extracorporeal anastomosis (EA) cohort. Results: IA was performed on 129 patients, while 213 underwent EA. Post-propensity score matching resulted in 129 matched pairs. After matching, many baseline characteristics were balanced. The IA cohort exhibited several advantages, including shorter incision lengths (P < 0.001) and more extensive proximal and distal resection margins (P=0.003, P < 0.001). Additionally, the IA method facilitated a more rapid postoperative recovery as indicated by quicker return of bowel movements (resumption of passing flatus [2.7 (1.0-7.0) days vs. 3.3 (2.0-8.0) days, P < 0.001] and defecation [3.7 (1.0-9.0)] days vs. 4.5 (2.0-9.0) days, P < 0.001]), faster discharges [6.6 (3.0-15.0) days vs. 8.3 (5.0-20.0) days, P < 0.001], and decreased need for rescue analgesics (P < 0.001). The rate of postoperative complications, as rated by the Clavien-Dindo classification, remained consistent across both techniques (P=0.087). Furthermore, the cosmetic outcome rated by Patient Scar Assessment Questionnaire and Scoring System (PSAQ) was markedly superior in the IA group (P < 0.001). Both approaches demonstrated equivalent 5-year overall (82.7% vs. 82.1%, P = 0.419) and disease-free survival (80.9% vs. 78.1%, P = 0.476). Subsequent stratification analysis revealed that IA achieved comparable 5-year overall (80.7% vs. 82.0%, P = 0.647) and disease-free survival (78.1% vs. 76.4%, P = 0.734) in patients with locally advanced colon cancer. Conclusion: Employing IA for laparoscopic segmental left colectomy in cases of splenic flexure carcinoma is not only safe but also offers enhanced cosmetic results and expedited postoperative recovery. Oncologically speaking, IA in left segmental colectomy for splenic flexure carcinoma can yield therapeutic outcomes comparable to those of EA, even in patients with locally advanced colon cancer.