Clinical features and outcomes of 9 patients with immunodeficiency-associated lymphoproliferative disorders treated at a single institution.

Immunodeficiency-associated lymphoproliferative disorders (LPD) represent a rare life-threatening clinical entity characterized by heterogeneous histological findings that range from polymorphic to monomorphic proliferated abnormal lymphocytes. Currently, there is no standard treatment for LPD. To elucidate the clinical features and treatment outcomes of immunodeficiency-associated LPD patients with rheumatoid arthritis (RA), we retrospectively evaluated 9 cases observed over a 5-year period. The diagnoses of these patients included 5 diffuse large B-cell lymphomas, 3 LPD, and 1 mucosa-associated lymphoid tissue lymphoma. At initial diagnosis, 6 patients had advanced-stage RA, and half of these underwent total knee arthroplasty. All patients with RA received methotrexate (MTX) and low-dose prednisolone. Biologics were administered to 4 of 9 patients. After the development of immunodeficiency-associated LPD, MTX discontinuation resulted in 5 complete remissions (CR), 1 partial remission, and 3 cases of stable disease. Relapse was observed in 3 of 5 CR patients in the MTX-withdrawal remission group. Subsequently, conventional chemotherapy, rituximab, and radiation were administered to 4, 3, and 1 patient, respectively. These treatments induced a second CR. In the chemotherapy group, 1 patient developed acute myocardial infarction and another experienced ileus and pulmonary abscess. In the rituximab group, no severe complications were observed. Consequently, all patients remained disease-free during the median 23-month follow-up period. Our results indicate that, depending on the RA disease stage, performance status, and extent of treatment response, less intensive treatments than those commonly indicated for non-Hodgkin lymphoma, involving MTX discontinuation and subsequent therapy containing rituximab, might be an efficient therapeutic strategy for immunodeficiency-associated LPD.