The effect of specialized cancer treatment centers on treatment efficacy in Hodgkin's lymphoma

Abstract

Background: The presumed benefits of centralization and minimum case numbers often guide health-policy decisions, but these benefits remain inadequately documented, particularly in oncology. In this study, we aim to measure the effect of the type of treatment center and/or the number of patients treated in it on the outcome of patients with Hodgkin's lymphoma.

Methods: From 1988 to 2002, 8121 patients with newly diagnosed Hodgkin's lymphoma were treated in Germany in multicenter randomized and controlled trials (RCTs) of the German Hodgkin Study Group (GHSG). Center-related effects on progression-free survival (PFS) were assessed univariately with Kaplan-Meier plots and log-rank tests, as well as with a multivariate Cox regression model.

Results: The 500 participating centers in Germany included 52 university hospitals, 304 non-university hospitals, and 144 medical practices specializing in hematology and oncology. No significant differences in PFS were found between patients from centers with high or low case numbers (5-year-PFS: 78.7% and 78.6% for centers with fewer than 50 and more than 50 patients, respectively) or from different types of centers [5-year-PFS: university hospital, 77.7%; non-university hospital, 79.4%; practice, 79.8%]. Even after statistical controls for the effect of other known and unknown prognostic factors and validation in further datasets, no center effects were found.

Conclusions: The type of center and the minimum number of patients treated in a center have no impact on the treatment outcome of patients with Hodgkin's lymphoma in Germany. In all GHSG centers, regardless of type, the quality standards for successful treatment are apparently met on all levels of patient care.

Figure 1

The data sets that were analyzed. G2, 2^nd trial generation; G3, 3^rd trial generation; G4, 4^th trial generation; PFS, progression-free survival.

Figure 2

Kaplan-Meier plots of progression-free survival (PFS) by caseload and type of center. Median follow-up, 6.7 years. a) PFS by caseload (at 5 years). Centers with < 50 pts.: 78.7%, 95% confidence interval (CI) 76%-81% (870 patients). Centers with ≥ 50 pts.: 78.6%, 95% CI 76%-81% (1353 patients). b) PFS by type of center (at 5 years). University hospital: 77.7%, 95% CI 75%-80% (1060 patients). Non-university hospital: 79.4%, 95% CI 77%–82% (1000 patients). Hematology-oncology practice: 79.8%, 95% CI 72%-85% (163 patients).