Pentostatin/cyclophosphamide with or without rituximab: an effective regimen for patients with Waldenstrom's macroglobulinemia/lymphoplasmacytic lymphoma.

Abstract

BACKGROUND:

Pentostatin has demonstrated significant activity as a single agent in patients with low-grade B-cell and T-cell lymphomas and is less myelosuppressive than other purine analogues.

PATIENTS AND METHODS:

We conducted a phase II trial with the combination regimen of PC-R (pentostatin/cyclophosphamide with or without rituximab) in 14 patients with Waldenstrom's macroglobulinemia (WM) and 3 patients with lymphoplasmacytic lymphoma (LL) without monoclonal serum immunoglobulin M (IgM), followed by a maintenance regimen with rituximab (375 mg/m2 every 3 months) for patients exhibiting a complete response (CR) or a partial response (PR) after 4-6 cycles. Nine patients were untreated, and 8 had been previously treated with 1-3 regimens. The first 9 patients received PC therapy (pentostatin 4 mg/m2 plus cyclophosphamide 600 mg/m2), and 8 patients received the same combination with rituximab 375 mg/m2 on day 1. Cycles were repeated every 3 weeks.

RESULTS:

An objective tumor response after PC and PC-R was confirmed in 11 of 17 evaluable patients (64.7%), with 2 CRs (11.7%) and 9 PRs (52.9%). In patients who received rituximab (n = 13) simultaneously or subsequently, the overall response rate was 76.9%. Grade 2/3 nausea and grade 2 vomiting was generally mild based on World Health Organization criteria. Grade 3 hematologic toxicity occurred after 9 of 49 cycles (18.3%), and grade 4 toxicity occurred after 2 cycles (4%). Ten patients were subsequently treated with rituximab every 3 months for 2-9 cycles to date (median, 4 cycles). No patients have had disease relapse to date, and all exhibited stable IgM serum levels. In 3 patients with a PR after completion of chemotherapy, remission has improved further, with normalization of the IgM level in 1 patient and another patient exhibiting a CR.

CONCLUSION:

Our data indicate that PC-R is safe and highly effective in patients with WM. Maintenance therapy with rituximab for WM as a single infusion every 3 months can be administered safely and can improve remission status.

• Authors: Manfred Hensel, Matthias Villalobos, Martin Kornacker, Fatime Krasniqi, Anthony D Ho
• Journal: Clinical lymphoma & myeloma (Clin Lymphoma Myeloma) Vol. 6 Issue 2 Pg. 131-5 (Sep 2005) ISSN: 1557-9190 [Print] United States
• PMID: 16231851 (Publication Type: Clinical Trial, Phase II, Comparative Study, Journal Article)

Chemical References

• Antibodies, Monoclonal
• Antibodies, Monoclonal, Murine-Derived
• Antineoplastic Agents
• Immunoglobulin M
• Pentostatin
• Rituximab
• Cyclophosphamide

Topics

• Adult
• Aged
• Antibodies, Monoclonal (administration & dosage, adverse effects)
• Antibodies, Monoclonal, Murine-Derived
• Antineoplastic Agents (administration & dosage, adverse effects)
• Antineoplastic Combined Chemotherapy Protocols (administration & dosage, adverse effects)
• Cyclophosphamide (administration & dosage, adverse effects)
• Disease-Free Survival
• Female
• Humans
• Immunoglobulin M (blood)
• Leukemia, Lymphocytic, Chronic, B-Cell (blood, drug therapy)
• Male
• Middle Aged
• Pentostatin (administration & dosage, adverse effects)
• Remission Induction
• Rituximab
• Waldenstrom Macroglobulinemia (blood, drug therapy)