Preoperative clinical and contrasted-enhanced CT features to predict perineural invasion in gallbladder carcinoma: focus on clinical T3-4 stage.

Purpose: To investigate the utility of combining clinical and contrasted-enhanced tomography (CECT) parameters for the preoperative evaluation of perineural invasion (PNI) in gallbladder carcinoma (GBC).

Methods: A total of 134 patients with GBC (male/female, 52/82; age, 64.4 ± 9.7 years) were divided into PNI-positive (n = 63) and PNI-negative groups (n = 71). Clinical characteristics (demographic information, liver function indicators and tumor markers) and CECT parameters (tumor type, tumor size, gallbladder stone, invasion of gallbladder neck/cystic duct, clinical T stage and N stage) were collected and compared between two groups. Binary logistic regression analysis, receiver operating characteristic curves analyses and Delong test were used in further statistical analyses in clinical T3-4 stage (cT3-4) GBC patients. Overall survival (OS) rates after surgery were compared between PNI-negative group and PNI-positive group of cT3-4 GBC patients.

Results: The majority of GBC patients with PNI were classified as cT3-4 (61/63, 96.8%), while only 3.2% (2/63) of PNI-positive cases were identified at cT1-2. Among cT3-4 GBC, OS was significantly lower in the PNI-positive group than the PNI-negative group after surgery (HR,1.661; 95% CI, 1.044-2.643; P = 0.032). Gender and gallbladder neck/cystic duct invasion were independent predictive factors for cT3-4 GBC patients with PNI. A combination of gender and gallbladder neck/cystic duct invasion showed the best diagnostic performance than that of individual parameters (all P < 0.05).

Conclusions: Preoperative T staging using CECT enables the initial assessment of PNI status in GBC patients. A combination of gender and gallbladder neck/cystic duct invasion may effectively predict PNI in GBC, particularly in cT3-4 GBC.