Small Intestinal Tumors: A Rare Case of Tubulovillous Adenoma in Duodenum

The small intestine is a relatively privileged organ; primary tumors are uncommon among malignancies of the gastrointestinal tract, with an average annual incidence rate of 9.9 per million people. Among these uncommon tumors, duodenal tumors are even rarer with an average incidence rate of 0.4% only. Histopathological examination mostly shows villous type. Tubulovillous histology is extremely rare with an incidence of less than 1% of all duodenal tumors. These tumors are either found incidentally or during screening for familial disorders such as familial adenomatous polyposis or Gardner's syndrome. Patients usually have symptoms such as diarrhea and abdominal pain along with weight loss over a period of months. Itching over the whole body and progressive yellow discoloration of sclera and skin (jaundice) can also be present when tumor compresses the common bile duct (CBD) and causes obstruction, especially in the region of ampulla of Vater. Examination of the abdomen may or may not reveal a mass lesion. Abdominal radiography and ultrasound show intra- and extra-hepatic biliary dilatation along with distention of CBD and growth at the lower end of CBD. Endoscopic retrograde cholangiopancreatography (ERCP) is, however, the investigation of choice as it not only allows direct visualization of a biliary tree but biopsy specimens can also be taken. Palliative procedures like placing a stent in the common bile duct to relieve obstruction can be done or a drain can be placed to drain bile. The definitive treatment is the Whipple procedure involving gastrojejunostomy, choledochojejunostomy, and cholecystectomy. Our case is unique as the patient had duodenal tubulovillous adenoma, a very rare tumor among the already uncommon duodenal tumors. The patient underwent Whipple procedure, T tube was placed, and feeding jejunostomy was done. An uneventful recovery occurred.