Two cases of early gallbladder cancer incidentally discovered by laparoscopic cholecystectomy.

In case 1, a 68-year-old woman with asymptomatic gallstones underwent laparoscopic cholecystectomy after radical mastectomy for breast cancer. Histological examination revealed gallbladder carcinoma with involvement confined to the mucosa and positive margin at the cystic duct. We resected the remnant cystic duct with open laparotomy. In case 2, a 63-year-old woman with a diagnosis of early rectal cancer underwent laparoscopic cholecystectomy for silent gallstones following transanal resection of the rectal tumor. Pathologic analysis illustrated a gallbladder carcinoma with wide mucosal spread and minimal invasion into the subserosal layer. No additional treatment was warranted. As laparoscopic cholecystectomy has become widely used, an increase in the number of resected cases of early gallbladder cancer can be expected, especially among asymptomatic gallstone patients. Additional treatment should be determined through meticulous microscopic investigation of the specimen, with special attention to the depth of invasion and the range of mucosal spread.