Childhood renal tumours with intravascular extension

To assess whether pre-operative chemotherapy reduces operative morbidity in children with intravascular extension of renal tumours.

Thirty children with intravascular extension of their renal tumour, treated in 10 different centres in the UK, were reviewed retrospectively.

Twenty-nine patients had nephroblastoma and one child had clear cell sarcoma (favourable histology in 23, unfavourable histology in six). Patients were classified into stage II (17 patients), stage III (three patients) and stage IV (10 patients). Ultrasonography had been performed in 29 patients and had correctly diagnosed intravascular extension in 11 (40%); computed tomography (CT) was accurate in 93% of patients. A pre-operative diagnosis was made accurately in 24 patients, with caval extension in 18 and atrial extension in six. Nine patients underwent primary surgery, whilst 21 had pre-operative chemotherapy followed by delayed nephrectomy. In the latter group, the intravascular thrombus diminished in 16 patients. Five patients died, one from tumour rupture and four from extensive or progressive tumour disease; the overall 2-year survival was 83%. Unfavourable histology did not adversely affect survival, and patients having pre-operative chemotherapy appeared to have a better outcome.

CT remains the best imaging modality to assess intravascular tumour extension. Pre-operative chemotherapy is recommended for patients with intra-caval extension of tumour. Those with intra-atrial extension or with hepatic vein obstruction (Budd-Chiari syndrome) may require a cardiopulmonary bypass and primary surgery.