Validation of a Score That Predicts Residual Disease in Incidental Gallbladder Cancer

Prospective Validation of a Residual Disease Predictive Score in Incidental Gallbladder Cancer

An incidental gallbladder carcinoma is detected in approximately 0.2% of the cholecystectomy specimens removed for presumed benign disease. In patients that meet specific criteria, a surgical re-operation is recommended to treat possible residual tumor disease not treated with the initial cholecystectomy. The presence of residual disease in the re-intervention specimen worsens the prognosis of patient survival, according to several published series. Patients with known or high-risk of residual disease may benefit from a specific strategy that would improve patient selection before attempting re-resection. A pathology-based score has been developed but has not been yet validated in an external series of patients. The use of pathological data from the initial cholecystectomy specimen could identify patients at risk of residual disease and aid in selecting a specific therapeutic strategy prior to attempting surgical re-exploration.

• Sample size: 30 (minimum).
• Statistical analysis: populations will be compared with chi-square test or Fisher's exact test (categorical variables) and Student's t test or Mann-Whitney U test (continuous variables). A univariate and multivariate logistic regression analysis will be performed to evaluate the predictive factors of residual disease. The Kaplan-Meier method will be applied for survival analysis and curves will be compared using log-rank test. Univariate and multivariate Cox proportional hazards ratio will be applied to determine the predictive factors of survival. Variables with p values inferior to 0.1 in the univariate analysis will be used to perform the multivariate analysis. Statistical significance is defined when p < 0.5. The statistical program used will be SPSS version 23.

Inclusion Criteria:

• All consecutive patients with a diagnosis of incidental gallbladder cancer requesting therapeutic evaluation in the participating hospital centers.

Exclusion Criteria:

• All patients with non-incidental gallbladder cancer.
• All patients with incomplete or deficient data collection.
• Patients without a signed informed consent.