A 79-year-old man was referred to our hospital for further investigation and treatment of a pancreatic tumor detected during impaired glucose tolerance and an evaluation of elevated serum carbohydrate antigen 19-9 (CA19-9). He had no chief complaint, but did have a history of DM that was being treated with dipeptidyl peptidase-4 inhibitor and sulfonylurea. Physical examination revealed no abnormal findings within the abdomen and laboratory examination revealed no anemia or hyperbilirubinemia. Glycated hemoglobin A1C (HbA1C) level was 7.0% and serum levels of carcinoembryonic antigen and CA19-9 were 1.3 ng/ml and 59.3 U/ml, respectively. Contrast-enhanced computed tomography (CT) revealed an ill-demarcated hypovascular mass, 15 mm in diameter, in the uncus of the pancreas. There were no findings that suggested vascular invasion or nodal or distant metastasis. Dilatation of the main pancreatic duct and multiple cystic lesions were also seen in the tail of the pancreas, with no mural nodules found. Endoscopic ultrasonography (EUS) revealed a hypoechoic mass in the uncus of the pancreas. EUS-guided fine-needle aspiration and cytology revealed PDAC. Dilatation of the main and branch pancreatic ducts was present in the tail of the pancreas, with a maximum diameter of the main pancreatic duct of 13 mm. These features suggested mixed-type IPMN with high-risk stigmata. A small (4.6 mm) mural nodule in the branch pancreatic duct was also found. We decided to resect IPMN, low-grade malignancy in the tail of the pancreas along with PDAC in the head of the pancreas, because the patient was elderly, but was considered to be fit on geriatric screening and the procedure of additional resection for IPMN would be only total pancreatectomy. Therefore, we elected to perform MSPP alternative to TP owing to the patient’s age, postoperative quality of life, and IPMN tumor grade, while splenectomy was also performed concerning the technical difficulty, time-consuming and perioperative complications related to spleen-preservation. First, we started the pancreaticoduodenectomy procedure and the pancreas was divided at the location of the superior mesenteric vein. The frozen specimen of the pancreatic stump was negative for cancer. We then performed the distal pancreatectomy and splenectomy. The divided line of the distal pancreas was 2 cm on the proximal side of the pancreatic tail tumor. Preoperative CT showed the dorsal pancreatic artery (DPA) branching from the proximal splenic artery (SpA). The SpA was divided at the distal dividing line of the pancreas, far enough from the origin of the SpA that dissection around the SpA and exposure of the DPA were prevented. The pancreas was divided together with the splenic vein using the Signia™ stapling system. Epithelial cells in the pancreatic tail stump showed no atypia on histopathology. Finally, 4.6 cm of the pancreatic body was preserved and 10 mg of ICG was intravenously administered. The presence of fluorescence in the pancreatic remnant was definitively confirmed with a fluorescence camera. The reconstruction was done via a modified Child method with modified Blumgart pancreaticojejunostomy. Histopathological examination revealed that the tumor in the uncus of the pancreas was PDAC (pT1cN1M0, pStage 2B, UICC 8th) and that complete resection was achieved. The other tumor in the tail of the pancreas was found to be an intraductal papillary mucinous adenoma with mild atypia. The postoperative course was complicated by an International Study Group of Pancreatic Fistula (ISGPF) classification grade B pancreatic fistula from the distal stump, but the patient recovered well with conservative drain management. Postoperative CT examination showed that the pancreatic remnant was well preserved with good blood supply and the DPA was preserved. The patient was transferred to a hospital 33 days after surgery. Serum C-peptide immunoreactivity (CPR) during fasting and 2 h after breakfast were 0.61 ng/ml and 0.27 ng/ml, respectively. Administration of an insulin preparation was necessary; however, blood glucose was relatively well-controlled and no symptomatic hypoglycemia occurred. At 2 months of follow-up, HbA1c level was 6.3%. No steatorrhea or malabsorption occurred when using pancreatic enzyme supplementation.