Solid-pseudopapillary tumor of the pancreatic head causing marked distal atrophy: a tumor originated posterior to the main pancreatic duct.

We report the case of a solid-pseudopapillary tumor (SPT) of the head of the pancreas causing occlusion of the main pancreatic duct (MPD) and marked pancreatic atrophy distal to the tumor disproportionate to the tumor size. A 15-yr-old girl was diagnosed with 5-cm solid-pseudopapillary tumor of the pancreatic head with marked distal pancreatic atrophy. Endoscopic retrograde cholangiopancreatography demonstrated obstruction of the MPD in the pancreatic head. We performed a duodenum-preserving pancreatic head resection to avoid postoperative exocrine and endocrine insufficiency. The surgical specimen showed the typical gross appearance of a SPT, with only a thin rim of pancreas anterior to the tumor. We believe that this presentation results when a tumor originates posterior to the MPD. Thus, whether or not pancreatic atrophy occurs depends strongly on the anterior/posterior relationship between the enlarging tumor and the MPD. The risk of SPT causing severe pancreatic atrophy should be kept in mind to avoid irreversible pancreatic insufficiency in young females.