Pathological invasion identifies T2 gallbladder carcinoma patients who benefit from radical cholecystectomy: a retrospective study of 77 cases

Background: The optimal surgical extent for T2 gallbladder carcinoma (GBC) remains debated, particularly regarding which patients truly benefit from radical cholecystectomy. This study evaluated the prognostic significance of pathological invasion (PI)—defined as lymphatic, venous, or perineural invasion—and explored PI-based criteria for selecting the appropriate surgical procedure. Methods: We retrospectively reviewed 77 patients with pathologically confirmed T2 GBC who underwent surgery between 1989 and 2024. Clinicopathologic variables, including tumor location (T2a/T2b), lymph node (LN) status, and PI, were analyzed. Disease-specific survival (DSS) was estimated using Kaplan–Meier curves, and prognostic factors were assessed using Cox regression. Results: PI was present in 42 patients (55%) and was strongly associated with LN metastasis (18%; odds ratio 15.24, 95% confidence interval 2.77–286, P = 0.02). PI-positive patients had significantly poorer 5-year DSS than PI-negative patients (50% vs 93%, P < 0.001). Among PI-positive patients, radical cholecystectomy (RC) significantly improved DSS compared with simple cholecystectomy (SC) (57% vs 25%, P = 0.04), whereas PI-negative patients showed excellent outcomes irrespective of surgical extent (96% vs 86%, P = 0.37). Tumor location (T2a vs T2b) was associated with DSS in univariable analysis, but lost independent significance after adjustment for PI and LN status, and did not predict benefit from RC. Conclusions: PI is a strong prognostic marker in T2 GBC and is the key factor identifying patients who benefit from RC. A PI-guided surgical strategy may help avoid unnecessary radical procedures in biologically indolent tumors while ensuring adequate oncologic treatment in high-risk patients.