The radiotherapy reference panel--experiences and results of the German Hodgkin Study Group (GHSG)

The German Hodgkin Study Group (GHSG) including more than 500 participating centers established a central radiotherapy (RT) reference center to improve quality of treatment. The purpose of the present article is to summarize the experiences and results of the performed and ongoing quality assurance programs (QAP) of RT.

A panel of expert radiation oncologists evaluated retrospectively the adequacy of treatment fields, applied radiation doses, treatment time and technical parameters. For the fourth study generation (HD10-12, 1998-2003), the RT reference center moved from Munich to Cologne. New RT QAP were initiated according to the demands of the new trials and former programs were enhanced.

A strong achievement in the era of extended field RT was to show that major deviations of radiation treatment portals and radiation dose from prospective treatment prescriptions were unfavorable prognostic factors for patients with early-stage Hodgkin's lymphoma (HL). The central prospective radiation oncological review of all diagnostic imaging showed that corrections of disease involvement in 49% of patients with early stages (HD10) and in 67% for patients with intermediate stages (HD11) were necessary. The introduction of electronic image transfer optimized and simplified the workflow of the QAP.

Today radiation oncologists in the GHSG perform efficient QAP to improve treatment quality of study patients. For early-stage HL a central prospective review of all diagnostic imaging is performed to control the disease extension and to define the IF treatment volume. Retrospective analysis of RT portals detects faults in the applied irradiation.