RT Journal Article SR Electronic T1 Adenocarcinoma of the fourth portion of duodenum presenting as intussusception: an unusual manifestation of rare pathology JF BMJ Case Reports JO BMJ Case Reports FD BMJ Publishing Group Ltd SP e244034 DO 10.1136/bcr-2021-244034 VO 14 IS 7 A1 Vaibhav Kumar Varshney A1 Bharti Varshney A1 Sudeep Khera A1 Binit Sureka YR 2021 UL http://casereports.bmj.com/content/14/7/e244034.abstract AB Primary adenocarcinoma of the fourth portion of the duodenum (D-IV) is reported infrequently than other parts of the duodenum. Its diagnosis is often late because of non-specific symptoms and signs. We encountered a 48-year-old male patient who was diagnosed as duodeno-duodenal intussusception, underwent segmental duodenal resection with duodenojejunal anastomosis and confirmed as adenocarcinoma of D-IV. He received adjuvant chemotherapy and is doing well at 1 year of follow-up. This report describes about the rare case of isolated adenocarcinoma of the D-IV presented as intussusception which is never reported before and successfully treated by segmental resection of the duodenum and jejunum.