Outcome of Nodular Lymphocyte Predominant Hodgkin Lymphoma Patients Treated with or without Rituximab

Strong CD20 expression in nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) suggests the feasibility of rituximab in the treatment of this disease.

We analysed the outcome of 102 patients with NLPHL treated with or without rituximab in combination with conventional treatment: chemotherapy and/or radiotherapy. Histologies were reviewed for the purpose of this study. Rituximab was administered in 26 of 102 NLPHL patients (13 in the first line treatment and in 13 of 20 relapsed patients). Additionally, rituximab with chemotherapy was administered in 11 patients with histologic transformation to diffuse large-B cell lymphoma. Median follow-up was 7.1 years. Median patient age was 34.2 years.

The 10-year overall survival (OS) rate and progression - free survival (PFS) of the whole group was 88% and 65%, respectively. There was no difference in OS and PFS in patients with clinical stage IA without risk factors treated without or with rituximab (30 vs 3 patients) and conventional treatment, however the follow-up in the rituximab group was short. The addition of rituximab to conventional treatment did not affect the OS in the group of patients with more advanced disease: 58 patients without vs 10 with rituximab (94% [95% CI: 88 – 100%] vs 100% [-], P=0.566). PFS in both groups did not differ significantly in the first line treatment (69% [95% CI: 57 – 82%] vs 100% [-], P=0.165), however when all lines of treatment were analysed, PFS was significantly better in patients treated without rituximab (92% [95% CI: 84 – 100%] vs 38% [95% CI: 22 – 65%], P< 0.001). Histologic transformation to diffuse large B - cell lymphoma was diagnosed in 11 rituximab naive patients, but this was not statistically significant when compared to 0 patients after rituximab treatment (14,5% vs 0%, P=0.061). Histologic transformation was the only poor prognostic factor that influenced OS (HR 7.936, P=0.004).

Rituximab does not prevent relapses in NLPHL. This study confirms favorable OS of NLPHL patients regardless whether rituximab was used or not. The absence of histologic transformation in NLPHL patients treated with rituximab deserves further investigation.

No relevant conflicts of interest to declare.