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.
Methods: 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.
Results: 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).
Conclusion: 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.