ABVD chemotherapy with reduced radiation therapy rates in children, adolescents and young adults with all stages of Hodgkin lymphoma.

Background: We adopted ABVD chemotherapy with risk-adapted radiation therapy (RT) as first-line therapy for children, adolescents and young adults with Hodgkin lymphoma (HL) in British Columbia in 2004. Patients and methods: Patients ≤ 25 years diagnosed from 2004 to 2013 with all stages of HL who received ABVD as initial therapy were included.
Results: Among 55 children (age < 18 year) and 154 young adults (18-25 year), there were no significant differences among age groups for sex, histologic subtype, tumour bulk, B symptoms, prognostic risk groups or treatment received. The rates of complete response, partial response and progressive disease were 84%, 7% and 10% for children and 95%, 4% and 1% for young adults (P=0.01), respectively. Treatment failures in children all occurred within one year of completion, while 8/21 (38%) relapses in young adults occurred later (P=0.04). With a median follow-up of 66 months the 5-year progression-free (PFS) and overall survival (OS) were 85 ± 3% and 97 ± 1%, respectively. For limited stage disease, PFS was 90 ± 7% for children and 93 ± 3% for young adults (P=0.65); OS was 100% for both. For advanced stage patients, PFS and OS were also similar for the children and young adults (77 ± 7% versus 81 ± 4%; P=0.38 and OS 90 ± 6% versus 97 ± 2%; P=0.17). The rate of consolidative RT was low (21%) and did not differ between age groups.
Conclusion: ABVD is an effective treatment in children, adolescents and young adults with HL. Children were less likely to achieve complete response and demonstrated earlier relapses compared to young adults. RT may be omitted for the majority of patients while maintaining excellent 5-year OS.