Clinical, pathologic, and radiologic data were reviewed on VHL patients who underwent surgery for a preoperative diagnosis of PNEN since 1994 at 1 institution. Blinded to the pathologic diagnoses, radiologists reassessed available imaging.
For 55 patients, 79 pancreatectomies were performed for presumed PNENs. Ten (18 % ) patients underwent 12 (15 % ) resections for neoplasms diagnosed as SMSA on final pathology. The average size of a SMSA leading to operation was 3.6 ¡À 0.4 cm. Four out of 11 SMSAs were still mistaken for PNENs when imaging was reassessed. The mean FDG-positron emission tomography (PET) standardized uptake value was greater for 17 PNENs (12.1 ¡À 1.2) compared with 6 SMSAs (4.2 ¡À 0.5; P = .002). The mean doubling time of SMSAs and PNENs was similar. Seven (15 % ) patients with pathologically proven PNENs had malignant disease.
SMSAs can mimic PNENs on nonfunctional imaging; FDG-PET may help to differentiate them. A high index of suspicion is needed to minimize operations performed for SMSA and to counsel VHL patients of their risks of undergoing operation for a lesion with no known malignant potential.