Background: Cystic nephroma (CN) and pleuropulmonary blastoma (PPB) are rare tumors without any previously recognized familial association.
Methods: Two cases of CN and one case of PPB in three siblings are reported.
Results: A 27-month-old girl and a 31-month-old boy underwent nephrectomy for CN and are free of disease in the contralateral kidney 16 and 14 years later, respectively. Their 28-month-old sister underwent pleuropneumonectomy with postoperative chemotherapy for PPB and died of recurrent disease 9 months later.
Conclusion: To the knowledge of the authors, these cases represent the first reported familial occurrence of CN and the second of CN and PPB among siblings. The inheritance of a germline mutation predisposing to the development of these tumors is postulated.