Identification of Prognostic Factors in Patients with Early Stage Unfavorable Hodgkin’s Lymphoma: An Individual Patient Data Meta-Analysis.

Background: In patients with early stage unfavorable Hodgkin’s lymphoma (HL) event-free-survival (EFS) is low compared to patients with early favorable or advanced stage disease. An international collaborative study was initiated to identify prognostic factors that could help to define among early stage unfavorable patients those who might benefit from more intensive treatment.

Methods: Medline and Cochrane Library were systematically searched for randomized controlled trials in stage I/II HL. Trials should concern patients with one or more risk factors (age, sex, stage, B-symptoms, bulky disease, number of areas involved, laboratory parameters) receiving 4–6 cycles of ABVD or similar chemotherapy and radiotherapy. Only trials with ≥ 100 patients per study arm were considered. Individual patient data were collected.

Results: Six studies were identified: GHSG: HD5, HD8, HD11; EORTC: H6U, H7U, H8U. Data from 4,235 patients enrolled between 08/1982 and 01/2003 were available for analysis. The proportion of missing data was very low for demographic and clinical characteristics (< 1%); it was acceptable (1.5–9%) for laboratory parameters with the exception of albumin (41% missing values, not recorded in 3 trials). Patient characteristics are listed below. The median follow up was 58.4 months (95% CI 56–61). At the time of analysis 612 patients had experienced an event (disease progression, relapse or death) leading to a 5-year EFS rate of 85%. Using an univariate Cox-regression stratified by study and treatment arm several parameters showed significant influence on EFS.

Conclusion: The data set available is sufficiently powered to identify relevant prognostic factors. A multivariate analysis using updated data will be presented.