Congenital mesoblastic nephroma: treatment options

Congenital mesoblastic nephroma (CMN) is an uncommon tumour in the neonatal period. Many CMNs are of “typical” histology and require no therapy other than nephrectomy. However, some are of “atypical” histology and are known to recur and metastasize. The use of chemotherapy in the atypical variant and in case of recurrence has been a matter of controversy. The presence of tumour at the excision margin seems to be the only important predictor of recurrence. The role of heminephrectomy for localised lesions has not been defined. Five cases of CMN seen at the Royal Children's Hospital, Melbourne, are discussed. Two of them were atypical histologically. One child had a heminephrectomy and is among the first to have had this procedure for CMN. Current treatment options are reviewed in relation to existing knowledge of the pathology and natural history of CMN.