Impact of centralized diagnostic review on quality of initial staging in Hodgkin lymphoma: experience of the German Hodgkin Study Group.

Accurate clinical staging is crucial for adequate risk-adapted treatment in Hodgkin lymphoma (HL) to prevent patients from under- or over-treatment. Within the latest German Hodgkin Study Group trial generation, diagnostic findings such as histopathology, computerized tomography imaging and clinical risk factors were re-evaluated by expert panels. Here, we retrospectively analysed 5965 patients and identified 399 in who major discordant findings changed their first-line treatment allocation. Histopathology review did not confirm the initial diagnosis of HL in 87 patients. Treatment allocation was revised in 312 of the remaining 5878 patients: 176 were assigned to a higher and 128 to a lower risk group, respectively; the correct treatment group remained unclear in 8 patients. Cases of revised treatment allocation accounted for 9·8%, 6·0%, 0·8%, and 14·8% of patients initially assigned to the HD13, HD14, HD15 trials and stage IA lymphocyte-predominant HL project, respectively. Most revisions were due to wrong application of clinical stage (20·5% of 312 patients with revised treatment group), histological subtype (9·0%) or the risk factors ≥3 involved areas (46·8%) or large mediastinal mass (9·3%). In conclusion, centralized review by experienced experts changed risk-adapted first-line treatment in a relevant proportion of HL patients. Quality control measures clearly improve the accuracy of treatment and should be implemented in clinical practice.