Long-term outcomes of extended versus segmental resection for transverse colon cancer: A population-based analysis based on the SEER database.

Objective: To investigate long-term cancer-specific outcomes associated with extended versus segmental colectomy (SC) in patients with stage I-III transverse colon adenocarcinoma using a large, population-based cohort.

Material and methods: Patients who diagnosed with transverse colon cancer undergoing curative-intent colectomy were identified from the surveillance, epidemiology, and end results database (2013-2019). Surgical procedures were categorized as extended colectomy (EC) or SC based on standardized procedural coding. 1:1 propensity score matching was performed to reduce selection bias and balance baseline characteristics. Cancer-specific survival (CSS) was analyzed using multivariable Cox proportional hazards regression.

Results: Among 18,799 eligible patients, 58% underwent EC. EC was more frequently performed in individuals with higher tumor stage (p<0.01) and those receiving adjuvant chemotherapy (26% vs. 23%, p<0.01). After matching (n=7.904 in each group), EC was associated with a higher rate of adequate lymphadenectomy (>12 lymph nodes retrieved: 94% vs. 89%, p<0.01). Five-year overall survival did not differ significantly between groups (65.6% for EC vs. 66.9% for SC, p=0.074). However, SC was associated with a modest but statistically significant improvement in CSS (84.3% vs. 81.7%, p<0.01). In adjusted analysis, surgical extent (HR=0.8376, p<0.001), along with age, sex, tumor grade, stage, and lymph node yield, were independently associated with CSS.

Conclusion: While EC is more commonly utilized in advanced-stage disease and facilitates higher lymph node retrieval, SC offers comparable-and potentially superior-CSS in selected patients. These findings support the consideration of a tailored surgical strategy based on tumor biology and individual patient characteristics.