Gallbladder cancer of two histological origins: A case report and review of literature

INTRODUCTION AND IMPORTANCE: Carcinosarcoma is an extremely rare subtype of gallbladder cancer with a worldwide prevalence of less than 1%. Carcinosarcomas are composed of a mixture of epithelial and mesenchymal components. Preoperative diagnosis of carcinosarcoma is challenging considering the non-specific clinical presentation and radiological findings. CASE PRESENTATION: A 63 years old female presented with right hypochondrium abdominal pain for 6 months. CA 19.9 level was high. Computed tomography of abdomen showed gallstones with enhancing wall thickening, along with enlarged portacaval lymph node. Endoscopic ultrasound-guided biopsy of porta hepatis lymph node was done which showed moderately differentiated adenocarcinoma. Hence, she underwent extended cholecystectomy with extended porta hepatis lymph node dissection. Final histopathological result showed carcinosarcoma (pT2a, pN1 M0). Unfortunately, she passed away 7 months post-operatively. CLINICAL DISCUSSION: The majority of patients with carcinosarcomas are asymptomatic but can develop unspecific symptoms in advanced stages. The diagnosis is usually made incidentally on histopathological examination. Surgical resection is the mainstay treatment and longer survival can be achieved if combined with chemotherapy and radiation therapy. BILCAP trial suggested that capecitabine can improve survival in patients with gallbladder cancer. Unfortunately, even with these treatment modalities prognosis remains poor with a survival rate ranging from 2.9 to 6 months. CONCLUSION: Gallbladder carcinosarcoma is a rare tumor with a poor prognosis. However, some cases reported a good survival rate after surgery. Further research is needed to understand the behavior of these tumors well and identify the role of chemotherapy and radiotherapy and which patients would benefit the most from surgery.