Initial response to salvage therapy determines prognosis in relapsed pediatric hodgkin lymphoma patients

BACKGROUND: Pediatric Hodgkin lymphoma (HL) is a highly curable disease; however, prognostic factors for the survival of patients who develop recurrent disease have not been clearly defined. METHODS: This was a retrospective analysis of 50 pediatric patients with HL who relapsed or progressed between 1990 and 2006 and who were retrieved with intense cytoreductive treatment regimens followed by autologous stem cell transplantation and radiation therapy. A Cox proportional hazards model was used to determine risk factors for second treatment failure and death. RESULTS: The median patient age was 16.1 years (range, 4.9-22.1 years) at the time of HL diagnosis. Fifteen patients developed progressive disease during therapy, 14 patients relapsed early, and 21 patients relapsed late. Patients who remained alive at the time of this study had been followed for a median of 4.4 years (range, 1.2-16.6 years). The 5-year overall survival rate for patients who had an inadequate response (n=14) to initial salvage therapy was only 17.9% (95% confidence interval [CI], 3.1%-42.5%) compared with 97.2% (95% CI, 81.9%-99.6%) for patients who responded (n=36; P < .0001). In a multivariate Cox regression analysis of overall survival, an inadequate response to initial salvage therapy was the only significant variable (hazard ratio, 43.6; 95% CI, 5.4-354; P=.0004). CONCLUSIONS: The current results indicated that pediatric patients with relapsed HL who have an inadequate response after initial primary salvage chemotherapy have a very poor prognosis and should be considered for novel therapies directed at biologic or immunologic targets.