[Therapy-associated late effects after irradiation of malignant diseases in childhood and adolescence. Feasibility analyses of a prospective multicenter register study]

Abstract

Background and purpose: Radiogenic late effects in children and adolescents have been evaluated retrospectively in most analyses, with small patient numbers. The German Group of Pediatric Radiation Oncology (APRO) has generated a concept for a prospective evaluation of radiation-associated late effects in childhood. The aim of this study was to evaluate the feasibility of a nationwide central database for the documentation of radiation parameters and side effects of all children treated within therapy protocols of the German Society of Pediatric Oncology and Hematology (GPOH).

Patients and methods: A study center has been implemented in Muenster, the documentation has started in July 2001 in few centers in a pilot phase. Since February 2004 the documentation is done countrywide. Detailed documentation forms have been designed for treatment parameters and for doses applied at organs at risk. Furthermore, a uniform toxicity documentation, according to the RTOG/EORTC criteria, was chosen. Patients were reported from the study centers of the GPOH to the study center. All information was collected and analyzed in the study center.

Results: Till July 31, 2005, 438 documentations of radiation and 579 toxicity documentations of side effects have been collected in the study center. 46 centers for radiotherapy in Germany and one center each in Austria and in Switzerland took part in the documentation. The quality of documentation regarding completeness and plausibility fulfilled the expected criteria in most cases. This feasibility analysis showed that important information about organ dose levels and side effects was documented in a large number of patients (Figures 1 and 2).

Conclusion: This prospective evaluation of radiotherapy and radiogenic side effects in children and adolescents will allow correlating doses at organs at risk and the incidence of acute and late sequelae in Germany. Further documentations and a longer follow-up are necessary to obtain powerful results.