A 14-year-old girl (Case 1) with respiratory distress during exercise was referred to our department after a pancreatic mass was detected by computed tomography (CT). Contrastenhanced CT scan showed a low-density mass measuring 2.5 × 2 cm in the body of the pancreas. Low signal intensity was seen on T1-weighted magnetic resonance imaging (MRI) and high signal intensity on T2-weighted MRI. We suspected solid-pseudopapillary neoplasm (SPN) of the pancreas and performed laparoscopy-assisted spleen-preserving distal pancreatectomy. The postoperative course was uneventful, and she was discharged on postoperative day 13. A 15-yearold girl (Case 2) with abdominal pain and fever was referred to our department after an abdominal cystic mass was detected by ultrasound examination. Contrast-enhanced CT showed a 4-cm well-circumscribed mass. Higher signal intensity was seen on T2-weighted MRI. We suspected SPN of the pancreas and performed laparoscopic spleen-preserving distal pancreatectomy. The postoperative course was uneventful, and she was discharged on postoperative day 8. Laparoscopic or laparoscopy-assisted surgery should be considered for SPN of the pancreas.

Primary mesenteric neuroendocrine tumor is extremely rare. Here we describe 2 cases of this disease. Case 1 was a 66-year-old man with a working diagnosis of gastrointestinal stromal tumor or mesenteric tumor who underwent laparoscopic tumor resection. Immunohistochemically, the final diagnosis was primary mesenteric neuroendocrine tumor G1. There has been no recurrence as of 25 months after surgery. Case 2 was an 80-year-old man with a working diagnosis of gastrointestinal stromal tumor or mesenteric tumor who also underwent laparoscopic tumor resection. Immunohistochemically, the final diagnosis was primary mesenteric neuroendocrine tumor G1. This is recurrence-free as of 36 months after surgery. Several cases of primary mesenteric neuroendocrine tumor have been reported, but most have been treated with open surgery. To date, there has been only 1 case of primary mesenteric NET that was resected in a pure laparoscopic procedure. In all 3 cases (including our 2 cases), the largest tumor diameter was 4 cm. It appears that laparoscopic surgery can be used to treat primary mesenteric neuroendocrine tumor of small size (＜ 4 cm) with minimal invasion.