Rituximab therapy is effective for posttransplant lymphoproliferative disorders after solid organ transplantation: results of a phase II trial.

BACKGROUND: Posttransplant lymphoproliferative disorders (PTLD) remain an uncommon complication of solid organ transplantation with a high mortality rate reported after conventional therapies. Alternative treatments such as rituximab have been explored.
METHODS: Eleven patients with PTLD, who were CD20 positive, received an intravenous dose of rituximab, 375 mg/m2, weekly x 4 weeks, repeated every 6 months for 2 years in responding patients. The median age of the patients was 56 years (range, 43-68 yrs), and 9 patients were male. The type of solid organ transplantation that these patients received included lung (five patients), kidney (four patients), heart (one patient), and kidney/pancreas (one patient). The median time from transplantation to a PTLD diagnosis was 9 months (range, 1-122 mos). Diagnostic B-cell histology was diffuse large cell lymphoma or polymorphous process. No patient had bone marrow or central nervous system involvement. Primary extranodal disease was noted in 82% of patients. Immunosuppressive therapy was decreased at the time of diagnosis.
RESULTS: Rituximab was well tolerated, with mild infusional blood pressure alterations noted in two patients. The median follow-up period was 10 months (range, 1-32 mos). The overall response rate was 64%, with 6 complete responses (CR), 1 partial response, 2 cases of progressive disease, and 2 deaths. The median duration of CR was 8 months (range, 2-19+ mos). The median time to treatment failure was 10 months (range, 5-25+ mos). The median survival was 14 months (range, < 1-32+ mos). Four patients were alive at the time of last follow-up.
CONCLUSIONS: Single-agent rituximab may offer a response and survival advantage in patients with PTLD. Further evaluation of rituximab in these disorders, potentially in combination with other therapies, is warranted. Copyright 2005 American Cancer Society