Dose-dense chemotherapy enables elimination of RT for the majority of low-risk pediatric Hodgkin lymphomas: PHC study HOD08

The Pediatric Hodgkin Consortium hypothesized that by increasing chemotherapeutic dose density for Hodgkin lymphoma (HL) they could increase the complete response (CR) rate among patients with favorable-risk HL after 8 weeks of Stanford V (vinblastine, doxorubicin, vincristine, bleomycin, mechlorethamine, etoposide and prednisone) compared with 8 weeks of VAMP (vinblastine, Adriamycin [doxorubicin], methotrexate, and prednisone). This would translate to a decrease in patients who required radiation therapy (RT) to achieve a cure. The HOD08 study was a phase 2 multicenter, investigator-initiated single-arm trial for patients aged ≤21 years with previously untreated stage 1A or 2A HL without mediastinal bulk or extranodal disease extension and <3 sites of disease. Treatment consisted of a modified 8-week Stanford V regimen. Modified, tailored, field RT was administered only to disease sites achieving less than a CR. The primary objective was to increase CR rate after 8 weeks of chemotherapy by at least 20% (from an estimated 44% to 64%) compared with patients treated on a previous trial (HOD99). HOD08 enrolled 85 patients with HL and 72 were evaluable for the primary objective, of whom 55 (76.4%) achieved a CR at all sites and did not receive RT. The 5-year event-free survival and overall survival rates for the entire cohort were 87.4% (95% confidence interval [CI], 80.4-95.0) and 98.7% (95% CI, 96.2-100), respectively. A dose-dense modified Stanford V regimen reduced the proportion of pediatric patients with low-risk HL who received RT while maintaining excellent outcomes. This trial was registered at www.clinicaltrials.gov as #NCT00846742.