Intracranial relapse in Wilms tumor patients

Background. In children with nephroblastoma, recurrence with metastases in the central nervous system is rare. Recently, previous reports (NWTSG and UKCCSG) reported brain metastases with an incidence of respectively 0.5% and 0.6% in Wilms tumor (WT) patients (respectively n = 30/5,852 and n = 7/1,249). Procedure. We retrospectively investigated the incidence and survival of patients with central nervous system relapse in WT patients, treated according to the consecutive SIOP protocols 1, 2, 5, 6, 9, and 93-01. All children with WT from 1971 until 2000 were enrolled in the study (3,040 eligible patients). Specimens at diagnosis and if possible at relapse were centrally reviewed. Patients with renal neoplasms other than WT were excluded. Results. CNS relapse was documented in 14 patients (0.5%). Median time to CNS relapse was 16 months (3-69). The occurrence of relapse was not associated with specific histological subtypes. In seven patients intracranial metastases occurred at first relapse, of which two were isolated relapses. In five patients no treatment was started because of the poor condition of the patient, the other nine cases were treated with (a combination of) chemotherapy (n = 6), surgery (n = 4), and radiotherapy (n = 6). Conclusions. CNS relapse in WNT is rare. In contrast to reports of other Wilms tumor study groups, although tour patients reached (local) CR, the SIOP registry showed that eventually none of the documented WT patients survived.