[Complete remission of relapsed mixed cellularity Hodgkin's disease treated with rituximab]

Cure rates of Hodgkin's disease (HD) with chemotherapy and/or radiotherapy are high. However, a few patients are refractory to treatment or relapse. We describe a patient with mixed cellularity (MC)-type HD with frequent relapses. As all Hodgkin's or Hogan-Reed-Sternberg (HRS) cells expressed CD20, treatment with the anti-CD20 monoclonal antibody rituximab was given.

A 55-year-old man presented with cervical lymphadenopathy. Biopsy revealed HD of MC type in stage IVA (Ann Arbor classification). Complete remission (CR) was achieved after six cycles of doxorubicin-bleomycin-vinblastin-dacarbazine (ABVD) and cyclophosphamid-vincristine-procarbazine-prednison (COPP) regimens. The first relapse occurred 12 months later and was treated with DEXA-BEAM and autologous peripheral blood stem cell transplantation. 7 years later, the patient relapsed again. Histology confirmed the initial diagnosis. Staging revealed a stage IVA. A partial remission was induced with two further DEXA-BEAM cycles (dexamethasone, BCNU [1,3-bis(2-chloroethyl)-1-nitrosourea], ectoposide, ara-C, melphalan). 4 months later, the disease progressed. Despite treatment with gemcitabine there was no response. As all Hogan-Reed-Sternberg (HRS) cells were CD20 positive, rituximab (monoclonal antibodies) was given at a dose of 375 mg/m2 once a week for 4 weeks in an outpatient setting.

Treatment was well tolerated. A complete remission was achieved 2 months later. No infectious episodes occurred. After 30 months, the patient relapsed again. A second treatment with rituximab yielded another complete remission which was maintained for 20 months.

HRS cells are derived from germinal center B-cells in more than 90% of cases, B-cell markers being present in 80% of classical HD. CD20 expressions vary from 21-80%. A few patients with HD treated with rituximab have been reported. Most of these cases had lymphocyte-predominant HD. In our patient the safety and efficacy of rituximab in relapsed CD20-positive classical HD of an MC type was demonstrated to achieve long-lasting remission.