The role of diagnostic radiology in the diagnosis and management of rhabdomyosarcoma in young persons.

Rhabdomyosarcoma is a rare tumour of mesenchyme-like tissue in which differentiation of rhabdomyoblasts has occurred. It is found mainly in infants and children. The prognosis, until recent years very grave, has been improved by a combination of chemotherapy and radiotherapy occasionally with surgery. Survival depends on the extent of the disease at the time of diagnosis. Diagnostic radiology has an important role to play in the demonstration of this, illustrations of which are given from a series of seven cases. The primary tumour has no pathognomonic appearances and is demonstrated essentially as a soft tissue mass lesion which displaces adjacent soft tissue structures such as arteries, veins, bladder and colon, or erodes adjacent bones whether in the extremities or the skull. The main role of diagnostic radiology is the detection of metastases. Chest radiography and skeletal survey are mandatory. Lymphangiography may reveal filling defects in regional lymph nodes but these are indistinguishable from any other metastases. Arteriography as well as revealing displacement of larger vessels, may show typical tumour neovascularity in the lesion. Serial skeletal radiographs are of help in assessing response of metastases to therapy.