When Adenocarcinoma Went Hand in Hand with Neuroendocrine Tumor: A Rare Case of Adenocarcinoma Synchronous with Neuroendocrine Tumor in Ampulla of Vater.

Neuroendocrine tumors (NETs) of gastrointestinal tract are rare entities. Their presence as synchronous lesions with adenocarcinoma has rarely been described in the literature. Cases of synchronous lesions of adenocarcinoma with neuroendocrine component have been described in the colon in the past. However, synchronous presence in the ampulla of Vater is quite uncommon. In the duodenum, NETs constitute 5.7 to 7.9% of the neuroendocrine neoplasms of the gastroenteropancreatic tract. We present a case of 65-year-old male who presented with abdominal symptoms and weight loss, was found to have adenocarcinoma of the ampulla of Vater on biopsy via endoscopic retrograde cholangiopancreatography (ERCP), for which he underwent Whipple's surgery and was found to have neuroendocrine component along with adenocarcinoma postoperatively on histology.