18F-FDG PET versus CT for the detection of enteropathy-associated T-cell lymphoma in refractory celiac disease.

Abstract

Refractory celiac disease (RCD) can evolve into enteropathy-associated T-cell lymphoma (EATL). 18F-FDG PET has been reported to discriminate between RCD and EATL. Because prospective data are lacking, we designed a prospective study to evaluate the potential of 18F-FDG PET for detection of EATL in patients with RCD and compared the results with those obtained using abdominal CT in a referral center. Between April 2003 and April 2005, 8 consecutive patients (median age, 66 y; range, 52-89 y) with EATL and 30 patients (median age, 61 y; range, 44-71 y) with RCD were included. CT and 18F-FDG PET were performed on all patients. Histologic evidence of EATL was identified in tissue samples obtained during upper gastrointestinal endoscopy or surgical resection. Villous atrophy was found in all patients with RCD and all (except 1) patients with EATL in nontumoral mucosa. Histologic examination of 1 patient with EATL localized in the duodenum showed intraepithelial lymphocytosis only. 18F-FDG PET could reveal sites histologically proven to be EATL in all 8 patients, whereas CT showed normal findings in 1 patient with EATL. 18F-FDG PET detected unsuspected extraintestinal sites affected by EATL in 2 patients. CT showed abnormalities such as a thickened small-bowel wall or lymphadenopathy in 14 patients with RCD lacking evidence of EATL at follow-up. 18F-FDG PET findings were positive in 3 and equivocal in another 3 patients with RCD. 18F-FDG PET was more sensitive and specific than CT (100% vs. 87% and 90% vs. 53%, respectively). Our data show that 18F-FDG PET is more sensitive in detecting EATL in patients with RCD than is CT. 18F-FDG PET, in addition to conventional CT, is recommended for evaluating patients with RCD.