Abstract
Carcinosarcoma is a malignant tumor that is a mixture of carcinoma (cancer of epithelial tissue and sarcoma (cancer of non-epithelial tissue). It occurs in a variety of organs, but rarely occurs in the gallbladder. So far only 45 cases of carcinosarcoma of the gallbladder have been reported in Japan.
A 71-year-old woman who was found having a 3 cm-sized tumor in the gallbladder underwent resection of the gallbladder bed with D2 lymph node dissection with a diagnosis of gallbladder carcinoma. Histopathology showed coexistence of adenocarcinoma cells and spindle-shaped, sarcomatous tumor cells, as well as transformation between them. Spindle tumor cells in the vicinity of the transformation were partly positive for an epithelial marker, and then “so-called carcinosarcoma” was diagnosed.
It has been reported that carcinosarcomas often present as papillary or nodular morphology. In our case the patient had a nodular tumor with a peducle that might be a difference from usual gallbladder carcinomas which often show the infiltrating property. Carcinosarcomas are believed to carry poorer prognosis than those of usual adenocarcinomas and most researchers agree a consensus that chemotherapies cannot be expected to exert effectiveness. However, our selection of S-1 therapy and the sustained administration for postoperative 24 months have provided a metastasis-free clinical course.
