Long-term efficacy and safety outcomes of the EORTC/LYSA/FIL H10 trial assessing early PET-scan adapted treatment of limited stage Hodgkin lymphoma

The treatment of patients with early stages of Hodgkin lymphoma (HL) with a combination of chemotherapy and radiotherapy is usually successful, with a 90% cure rate. Researchers continue to look for ways of further improving tumour control while also aiming to reduce the toxicities caused by treatments. The EORTC/LYSA/FIL H10 trial randomised early-stage HL patients into two groups: the first received ABVD¹ chemotherapy followed by involved-node radiotherapy (INRT, where only the lymph nodes originally involved are treated) regardless of their early PET scan result (early PET is the repeat scan after two cycles of ABVD). In the second, early PET-negative patients  (those whose tumours were no longer visible on a scan) received ABVD only, to assess whether omitting INRT results was not detrimental in terms of disease outcome while reducing toxicity. Those who were early PET positive (with still-visible tumours) switched to intensified treatment with BEACOPP² chemotherapy followed by INRT, to assess whether treatment intensification resulted in improved disease outcomes.

The long-term results presented relate to the 1,419 patients analysed, out of the total 1,925 in the main study analysis conducted at five-year follow-up. Results from the 10-year follow-up, presented at the International Conference on Malignant Lymphoma in Lugano, Switzerland, show that early PET-negative patients who did not receive the INRT had a lower progression-free survival time than those who received INRT. This applies especially to patients with initial favourable prognostic characteristics. However, long-term overall survival did not differ between patients with and without INRT.

At the five-year follow-up, the patients in the early PET-positive group showed significant benefit from the intensification of chemotherapy, with a five-year PFS improvement of 14%. But at 10 years, this benefit was no longer significant, with a 10-year PFS difference of only 6%. “However, the good news is that neither INRT nor the switch to the BEACOPP regime was associated with an increase of late toxicities,” says study leader Dr Massimo Federico, from the Fondazione Italiana Linfomi, Alessandria, Italy.

^1. ABVD chemotherapy is a combination of doxorubicin hydrochloride, bleomycin, vinblastine, and dacarbazine
^2. BEACOPP is a combination of bleomycin, etoposide, doxorubicin, cyclophosphamide, procarbazine, vincristine, and the steroid prednisolone