Pretherapy Gallium-67 scanning in paediatric patients with Hodgkin's disease.

OBJECTIVE To investigate the correlation between gallium-67 (67Ga) uptake and histological subtypes of Hodgkin's disease (HD) in paediatric patients. SUBJECTS AND METHODS Fifty-eight patients (45 males and 13 females aged 9.2 +/- 4 years, range 1.5-17 years) with histologically diagnosed HD underwent pretherapy 67Ga scanning on days 2, 5, 12 or 14 days after intravenous administration of 25-50 MBq (0.7-1.4 mCi) of 67Ga citrate. The scans were evaluated both visually and quantitatively using the activity of 67Ga in the liver as a reference. Clinical outcome of 11 patients with high diffuse 67Ga skeletal uptake was compared with that of 17 patients showing normal distribution of 67Ga in the skeleton. RESULTS Of the 58 patients, the 67Ga scans were positive in 47 patients with 117 lesions. Visual analysis did not differentiate between the histological variants of HD. However, quantitative analysis of lesion-to-liver ratios showed significantly higher values of 67Ga uptake in the mixed cellularity type than in the nodular sclerosis type (t = -3.7, p < 0.001). Patients with high skeletal uptake had a higher relapse rate (6/11) than those with normal skeletal uptake (3/17). CONCLUSION The findings show that quantitative analysis of 67Ga uptake can differentiate between the two main subtypes of HD (mixed cellularity and nodular sclerosis). Further diffuse skeletal uptake of 67Ga indicates a higher relapse rate.