Resection of lung metastasis from gallbladder carcinoma: immunohistochemistry of RCAS1 and CD8+T cells in primary and metastatic tumors.

Advanced Gallbladder cancer has an extremely poor prognosis. We examined a patient with resectable gallbladder cancer with associated lung metastasis. A 64-year-old female patient, diagnosed with gallbladder cancer and a solitary benign lung tumor by imaging, was subjected to extensive cholecystectomy and extrahepatic bile duct resection. After one year, a follow-up CT indicated enlargement of the lung tumor; video-assisted right middle lobectomy was then performed. The lung tumor was diagnosed as a metastasis derived from the gallbladder cancer by pathology and immunohistochemistry. Expression of RCAS1, an independent unfavorable prognostic indicator in gallbladder cancer, was observed in both the gallbladder and lung tumors. However, infiltration of CD8+T cells was only seen in the lung metastatic tumor. She has remained free of any evidence of recurrence in the 10 months and 4 years after the first surgery. The results that metastasis is solitary and infiltrated by CD8+T cells correspond with the present clinical history.