Morbid obesity is a recognized risk factor for gastrointestinal cancer. Little is known about pancreatic cancer developing after gastric bypass surgery or about surgery for this type of tumor following bariatric surgery. This report describes a case of pancreatic head cancer identified 3 months after laparoscopic sleeve gastrectomy for morbid obesity. During routine follow-up, mild abdominal pain and elevated pancreatic enzymes prompted computed tomography, which revealed mild edematous pancreatitis. Hyperbilirubinemia developed, and magnetic resonance imaging showed a pancreatic head tumor. CA19-9 was elevated. After a pylorus-preserving pancreatic head resection, the postoperative course was uneventful. The patient received adjuvant chemotherapy. Unfortunately, at the time of writing (9 months postoperatively), a local recurrence and hepatic metastases were diagnosed. Patients treated with bariatric surgery who develop new symptoms or report constant mild symptoms should be evaluated using endoscopy and radiomorphological imaging. Interdisciplinary obesity treatment can then offer significant benefits for the patient, particularly in the case of pancreatic cancer, which is still difficult to diagnose. In addition, there is a need for epidemiological studies of patients who undergo bariatric surgery and subsequently develop cancer.