Metastatic neuroblastoma: new abnormalities on bone scintigraphy may not indicate tumour recurrence.

Neuroblastoma is a potentially curable childhood malignancy with survival rates of 20% reported even in advanced disease. Technetium-labelled methylene diphosphonate (Tc99m-MDP) scanning is well established as a method of assessing bone disease. We report four patients, with advanced neuroblastoma in complete or partial remission, in whom new abnormalities on bone scintigraphy were due to benign lesions. Correct management depends on the precise diagnosis of such lesions.