Role of Limited Whole-Body PET/CT in Pediatric Lymphoma

OBJECTIVE. Performing true whole-body FDG PET/CT is standard practice in pediatric lymphoma staging and follow-up. In adults, imaging is typically limited whole-body PET/CT, which has advantages over true whole-body PET/CT, primarily decreased scanning time and decreased radiation. We hypothesize that in pediatric lymphoma, limited whole-body PET/CT is sufficient for routine follow-up when disease on the true whole-body staging study is confined to the limited whole-body field of view (FOV). MATERIALS AND METHODS. True whole-body PET/CT studies performed for staging and follow-up of pediatric lymphoma patients between November 2004 and July 2009 at two tertiary pediatric referral hospitals were retrospectively reviewed. Abnormalities on the limited whole-body and additional true whole-body FOV were documented. RESULTS. One hundred seventy patients met the inclusion criteria (752 examinations). At staging, disease involved the limited whole-body FOV without involving the additional true whole-body FOV in 150. Of the 150, 145 had routine follow-up (508 examinations). In these patients, no new F-18-FDG-avid disease was identified outside of the limited whole-body FOV on routine follow-up (positive predictive value, 0%, 95% CI, 0-0.02). CONCLUSION. The limited whole-body PET/CT for routine follow-up when disease is confined to the limited whole-body FOV at staging is appropriate. Given its definite advantages over true whole-body PET/CT, it is preferred.