Primary adenosquamous carcinoma of ampulla of Vater—A rare case report

INTRODUCTION: Primary adenosquamous carcinoma (ASC) of the ampulla of Vater (AmV) is extremely rare. Carcinoma of the ampulla of Vater tends to manifest early due to biliary outflow obstruction, as opposed to pancreatic neoplasms that often are advanced at the time of diagnosis. Periampullary carcinomas are treated by pancreaticoduodenectomy (PD). Adenosquamous carcinoma carries very dismal prognosis. PRESENTATION OF CASE: Here we present a case of 58-year-old male who was presented with abdominal pain, jaundice and anorexia with no history of (h/o) pruritus and clay colored stool. All blood investigations were normal except liver function tests (LFTs). Ultrasonography (USG) of abdomen suggestive of periampullary mass with dilated pancreatico-biliary tree. Endoscopic retrograde cholangiopancreatography (E.R.C.P.) demonstrated large deformed and bulky papilla with ulcerated lesion with infiltration in to duodenum. Exploratory laprotomy proceeds Whipple's pancreaticoduodenectomy done. Histopathology revealed adenocarcinoma of the ampulla of Vater. Immunohistochemistry was confirmatory of adenosquamous carcinoma. DISCUSSION: Adenosquamous carcinoma (ASC) is defined as a tumor in which both glandular and squamous elements are histologically malignant. Compared to adenocarcinoma, ASC of the AmV is a rare malignancy. Preoperative diagnosis is difficult because of the lack of defining characteristics in imaging studies and the difficulty in acquiring both malignant components by limited biopsy. Periampullary carcinomas are treated by pancreaticoduodenectomy. CONCLUSION: Adenosquamous carcinoma is a very rare form of cancer of the AmV. Pancreaticoduodenectomy is the treatment of choice though early recurrence and distal metastasis may be encountered after surgery. Follow-up should be more frequent to detect possible early recurrence and distal metastasis.