Advanced Hodgkin disease with large mediastinal involvement can be treated with eight cycles of chemotherapy alone after a major response to six cycles of chemotherapy: a study of 82 patients from the Groupes d'Etudes des Lymphomes de l'Adulte H89 trial.

Background: The prognostic impact of large mediastinal involvement (mediastinum/thorax [M/T] ratio > 0.33) in advanced Hodgkin disease (HD) and the optimal treatment with chemotherapy or combined treatment remains controversial.

Methods: Among 533 assessable patients with Ann Arbor Stage IIIB/IV HD included in the H89 trial, 82 had large mediastinal mass defined on chest X-ray. All patients received induction with six cycles of chemotherapy (mechlorethamine, vincristine, procarbazine, prednisone-doxorubicin, bleomycin, vinblastine or doxorubicin, vinblastine, bleomycin, procarbazine, prednisone); then complete and good partial responders were randomized between two consolidation treatments: 2 cycles of the same chemotherapy or (sub)total lymph node irradiation.

Results: Among 82 patients with an M/T ratio greater than 0.33, 48 were very large (ratio > 0.45). A large mediastinal mass was associated with supradiaphragmatic disease, younger age, histologic nodular sclerosis, and different sex ratio compared with other H89 trial patients. Biologic parameters and prognostic factors were similar for both groups. Although the major response rate to induction chemotherapy (after 6 cycles) was lower for patients with large mediastinal mass (78% vs. 86%), the 5-year overall survival rate (80% vs. 79%) and event free survival rate (59% vs. 61%) were similar (P = 0.64 and 0.3, respectively). The outcome was the same for patients (74%) with a large mediastinal mass randomized to 1 of the 2 consolidation arms. Analysis of progression showed that 68% (21 of 31) of failures occurred early during treatment and involved the mediastinum in 86% of the cases.

Conclusions: For patients with large mediastinal mass and advanced HD who achieved a major response of at least 75% after 6 cycles of chemotherapy, a consolidation radiation therapy can be replaced by 2 additional cycles of chemotherapy.