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

Study Overview
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Brief Summary
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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.

Detailed Description
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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.

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

Conditions
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Gallbladder Neoplasm Malignant Primary

Intervention / Treatment
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* Procedure: Radical surgery


Participation Criteria
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Eligibility Criteria
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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.
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Residual disease<br>Participants with incidental gallbladder cancer with presence of residual disease in the re-resection specimen or in intra-operative findings. | Procedure: Radical surgery<br>* Radical surgery is proposed to participants with pT1b, pT2 or pT3 tumors in the cholecystectomy specimen without evidence of disseminated disease with staging imaging techniques. A resection of the gallbladder bed or an anatomic resection of the hepatic segments IVb/V is performed. A lymphadenectomy of the hepatic hilum is associated in all cases. Common bile duct resection is performed in patients with involvement of the cystic margin.<br>|
| No residual disease<br>Participants with incidental gallbladder cancer with absence of residual disease in the re-resection specimen or in intra-operative findings. | Procedure: Radical surgery<br>* Radical surgery is proposed to participants with pT1b, pT2 or pT3 tumors in the cholecystectomy specimen without evidence of disseminated disease with staging imaging techniques. A resection of the gallbladder bed or an anatomic resection of the hepatic segments IVb/V is performed. A lymphadenectomy of the hepatic hilum is associated in all cases. Common bile duct resection is performed in patients with involvement of the cystic margin.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Residual disease | Presence of tumoral cells in the re-resection specimen or found on staging imaging techniques. It can be local (isolated non-discontinuous involvement of the vesicular bed or the cystic stump), regional (common bile duct involvement, perineural, lymph node or neighboring organ invasion), or distant (discontinuous hepatic involvement -i.e. metastases-, peritoneal carcinomatosis or port-site metastases). | Immediately after surgery in operated patients / within 1 year in non-operated patients | 
| Gallbladder cancer risk score | Pathology-based score that uses T stage, grade of differentiation, presence of lymphovascular and perineural invasion evaluated in the cholecystectomy specimen to pre-operatively predict the presence of residual disease after radical resection. Each factor is assigned a value. Adding these values results in a total risk score that ranges between 3 and 10 points. The scores are separated intro three risk groups: low (3-4), intermediate (5-7) and high (8-10). | Baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Disease-specific survival | Interval between date of surgical re-exploration and date of last follow-up or death. Only death from cancer will be considered an event in the analysis. Non-cancer related deaths will be excluded from the analysis. | 1, 3, and 5-year disease-specific survival. | 
| Disease-free survival | Interval between date of surgical re-exploration and date of recurrence diagnosis (clinic, radiologic or pathologic) or last follow-up or death in patients without recurrence. | 1, 3, and 5-year disease-free survival. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Residual disease, Risk score