Coincidence-detection FDG-PET versus gallium in children and young adults with newly diagnosed Hodgkin’s disease

Coincidence-detection 18F-FDG-PET (PET) and 67Ga whole-body and SPECT (Ga) were compared in children and young adults with newly diagnosed Hodgkin’s disease (HD). Materials and methods: Thirty patients with histologically confirmed HD underwent PET with attenuation correction 1 h after injection of 150–220 MBq 18F-FDG and whole-body and SPECT imaging 72 h after injection of 250–370 MBq 67Ga citrate. Two experienced readers retrospectively reviewed PET and Ga scans, grading 13 anatomic regions from one (normal) to five (abnormal). Numerical stages were assigned based on Ann Arbor classification. Comparison was made with disease sites (established by biopsy or two or more of the following: physical examination, conventional imaging studies, radionuclide studies, and follow-up studies) and clinical stages. Sensitivity, specificity, and accuracy were calculated and significance of differences determined using McNemar’s test. Results: PET detected 120/138 (87%) disease sites and Ga 109/138 (79%). PET and Ga were concordant for 103/138 (75%) sites. Accuracies were not significantly different for supradiaphragmatic disease. PET was more accurate than Ga for detecting splenic (0.91 vs 0.61, P=0.012), infradiaphragmatic (0.89 vs 0.75, P=0.042), and all disease sites combined (0.95 vs 0.91, P=0.039). PET stage agreed with clinical stage in 79% of patients and Ga in 71%. Conclusion: PET was superior to Ga for evaluating children and young adults with newly diagnosed HD.