Unexpected gallbladder cancer: Surgical strategies and prognostic factors.

Gallbladder cancer is the most common tumor of the biliary tract and it is associated with a poor prognosis. Unexpected gallbladder cancer is a cancer incidentally discovered, as a surprise, at the histological examination after cholecystectomy for gallstones or other indications. It is a potentially curable disease, with an intermediate or good prognosis in most cases. An adequate surgical strategy is mandatory to improve the prognosis and an adjunctive radical resection may be required depending on the depth of invasion. If the cancer discovered after cholecystectomy is a pTis or a pT1a, a second surgical procedure is not mandatory. In the other cases (pT1b, pT2 and pT3 cancer) a re-resection (4b + 5 liver segmentectomy, lymphadenectomy and port-sites excision in some cases) is required to obtain a radical excision of the tumor and an accurate disease staging. The operative specimens of re-resection should be examined by the pathologist to find any "residual" tumor. The "residual disease" is the most important prognostic factor, significantly reducing median disease-free survival and disease-specific survival. The other factors include depth of parietal invasion, metastatic nodal disease, surgical margin status, cholecystectomy for acute cholecystitis, histological differentiation, lymphatic, vascular and peri-neural invasion and overall TNM-stage.