Bone and gallium scintigraphy in children with rhabdomyosarcoma: a 10-year review

Technetium-99m bone and Gallium-67 scintigraphy has been widely used in the management of children with solid tumors. A retrospective review of all patients with rhabdomyosarcoma (RMS) from January 1980 to December 1989 was undertaken in order to determine the sensitivity and specificity of scintigraphy in detection of metastatic disease and to determine optimum frequency of serial scans in follow up. Over the 10-year period, 40 patients were diagnosed and treated for RMS: 22 were newly diagnosed from 1980-1984 and of these 16 had a minimum 5-year disease-free period whilst 6 died of the disease, giving a cure rate of 73%. A total of 271 bone and 236 Gallium-67 scans were performed. With respect to detection of metastatic disease in all tissues, Gallium-67 scans had a sensitivity of 84%, specificity 95% and bone scans had a sensitivity of 70% and specificity 95%. Bone scan sensitivity and specificity for skeletal metastases were 100% and 95%, respectively. Considering only patients with Gallium avid primary tumors, the Gallium-67 scan sensitivity was 94%. Ten patients developed new metastatic disease or primary recurrence after starting therapy, 8/10 within 12 months of diagnosis. Frequent surveillance scanning in the treatment phase, 2 years post-diagnosis, is of value in the early detection of metastases and monitoring disease response to therapy. Surveillance scanning after completion of treatment is more difficult to justify.