Patient 2, a 63-year-old man diagnosed with T-cell LGLL in July 2011. Seropositive erosive RA was diagnosed in November 2011, and low-dose methotrexate and prednisone were started. Three months later, neither the joint disease nor the leukemia was improved. Two 1000-mg rituximab infusions provided a rapid remission of the joint disease accompanied with immediate neutrophil count normalization despite persistence of the monoclonal T-cell population. Six months later, a second rituximab course was given for exacerbation of the joint symptoms. In January 2013, the RA was still in remission despite prednisone discontinuation, neutrophil counts remained normal, and the leukemic cell count was substantially decreased. DAS28, RA disease activity score evaluating 28 joints; MTX, methotrexate.