Prognostic impact of lymphovascular invasion in pT1-T3 gallbladder adenocarcinoma.

ABSTRACT

BACKGROUND: Most gallbladder cancers are diagnosed after cholecystectomy for presumed benign disease, and nodal staging to inform subsequent treatment is therefore often lacking. We evaluated the association of lymphovascular invasion (LVI) with regional lymph node involvement in gallbladder adenocarcinoma and its impact on survival. METHODS: The National Cancer Database was queried to identify patients with resected gallbladder adenocarcinoma and with available staging and LVI status. Patients with pT4 and M1 disease were excluded. Univariable and multivariable regression identified factors associated with positive lymph nodes. Cox proportional hazards model was used to evaluate overall survival (OS). RESULTS: Of 1649 patients with available LVI status, 1142 (69.7%) had at least one positive lymph node and 765 (46.4%) had LVI. On multivariable regression, presence of LVI was the strongest predictor of positive lymph nodes (odds ratio, 3.69; P < .001). The positive predictive value of LVI for positive lymph nodes in pT2 and pT3 tumors was 80.1% and 90.5%, respectively. LVI was independently associated with decreased OS (hazard ratio, 1.21; P = .001), as were node-positive disease and increasing T stage. CONCLUSION: In patients with gallbladder adenocarcinoma, LVI is independently associated with regional lymph node metastases and abbreviated OS. LVI status may help risk-stratify patients following initial cholecystectomy and inform subsequent treatment.