Spectrum of FDG uptake in large (>10 cm) esophageal leiomyomas.

Esophageal leiomyomas are rare benign tumors that can be treated successfully with limited surgical resection. It is occasionally important to distinguish leiomyomas from more aggressive submucosal esophageal tumors, most notably gastrointestinal stromal tumors (GISTs). GISTs have a worse prognosis, particularly when they are large (>10 cm). Increased uptake of (18)F-fluorodeoxyglucose on positron emission tomography (PET) scans is common in GISTs, potentially allowing PET scanning to differentiate between GIST and benign esophageal tumors. Three patients presented with large (>10 cm) esophageal masses of ranging PET avidity [maximum standardized uptake value (SUVmax) of 1.3-10.1]. All were treated surgically and histologically confirmed to be esophageal leiomyomas. Unfortunately, the wide range of PET uptake precludes PET scanning from differentiating large leiomyomas from more aggressive lesions.