In Pediatric Institute of Medical University of Gdańsk in all children with neoplasmatic diseases the echo examination is performed, due to exclude coexisting abnormalities of cardiovascular system. During this kind of procedure in 4.5-year-old girl with Wilms tumour the persistent ductus arteriosus was described. Because of the chemotherapy design and its potential cardiotoxicity the closure of PDA using coils was performed immediately. The successful closure of PDA gave the chance to apply the whole therapeutic protocol.