A Case Report on Adenosquamous Carcinoma of Gallbladder: A Very Rare Malignancy.

Gallbladder (GB) carcinoma is a rare carcinoma with a poor prognosis. The prevalence is 0.7-21/100,000 worldwide and 1-2/100,000 in the United States. Adenosquamous cell carcinoma is composed of glandular and squamous components. The overall five-year survival rate is less than 5%, with a median survival of fewer than six months. We are presenting a case of adenosquamous carcinoma of the GB in a 76-year-old female who presented with right upper quadrant abdominal pain and was found to have an enlarged GB, with thickened irregular wall likely inflammatory or malignant and mildly dilated common bile duct on ultrasound imaging of the abdomen. Core needle biopsy of GB showed findings compatible with adenosquamous carcinoma and immunohistochemistry was positive for P40, CK5,6. She was diagnosed with stage T4 N0 M0. She was started on chemotherapy with cisplatin and gemcitabine (25 mg/m2 and 1000 mg/m2), respectively, every three weeks but her condition worsened after the fifth cycle of chemotherapy and she decided to move forward with hospice care given her bad prognosis. Unfortunately, she passed away one week after being discharged home.