Excessive Vomiting with Normal Upper Endoscopy: A Case of Third Segment Duodenal Adenocarcinoma

Background A male patient complained of excessive vomiting and significant weight loss. We performed upper and lower endoscopy which were normal, not explaining his complaint. Upon further investigations, CT abdomen was performed with oral and IV contrast which showed duodenal thickening of the third part. On performing single balloon enteroscopy he is finally diagnosed as adenocarcinoma in 3rd segment of the duodenum and referred for Whipple’s operation. Case presentation: Here, we report a 60 -year-old male patient with excessive vomiting and significant weight loss. Full labs as liver, kidney and thyroid functions were normal. Upper and lower endoscopy were done, showing no abnormality. With a high suspicion to exclude malignancy, CT abdomen with oral and IV contrast showed thickening of the third duodenal segment (this segment was not examined as routine upper endoscopy examines until the second part of the duodenum. A single balloon Enteroscopy was done showing a fungating mass in the 3rd duodenal part, biopsy confirmed the diagnosis as duodenal adenocarcinoma and referred to surgery for Whipple’s operation. Conclusions One of the rare causes of excessive vomiting is duodenal malignancy especially in the third part (which isn’t routinely examined by upper endoscopy), and we must thoroughly exclude all causes of vomiting before diagnosing psychogenic vomiting.