The treatment of patients with advanced or therapy-refractory cutaneous T-cell lymphoma (CTCL) remains a challenge. Pentostatin is a potent inhibitor of adenosine deaminase and is selectively toxic to lymphocytes. In a small number of patients with CTCL, it previously has been shown to be effective.

Our purpose was to evaluate the efficacy and safety of pentostatin in the treatment of patients with advanced and/or therapy-refractory CTCL.

Eighteen patients with stage I to IVb CTCL were treated with 4 to 5 mg/m² of intravenous pentostatin every 1 to 4 weeks.

Two patients (11%) had complete responses of 4 months and 6 years, respectively. These patients had stage III and IVa CTCL and had previously received many different external or systemic treatments. Partial remission (50% to 99% clearing) lasting for 1.5 to 6 months occurred in five patients (28%) with stage Ila (n = 3), stage 11b, and stage IVa CTCL. These patients had received a median of three prior external or systemic treatments. No major side effects were observed, and bone marrow suppression was mild.

Single-agent pentostatin in intravenous doses of 4 to 5 mg/m² is an effective systemic treatment of CTCL (39% objective response rate) with little toxicity.