Molecular techniques in hematopathology

Phase 2 study of fludarabine and paclitaxel in patients with recurrent low-grade non-Hodgkin's lymphoma

Although numerous options are available for patients with recurrent low-grade non-Hodgkin's lymphoma (NHL), responses are rarely durable. We previously conducted a phase I trial of fludarabine and paclitaxel in the treatment of recurrent low-grade lymphoma. The present phase II study was performed to determine the activity of fludarabine and paclitaxel in patients with recurrent low-grade NHL. Patients with histologically confirmed recurrent low-grade NHL were treated with fludarabine 20 mg/m2/day intravenously (i.v.) on days 1-5 plus paclitaxel 50 mg/m2 given by i.v. continuous infusion over 72 h starting on day 1. Treatment was repeated at 4-week intervals for a maximum of six courses. Twenty-eight evaluable patients were entered into this phase II trial. The median age was 53 years and the median performance status (Zubrod) was 1. Twenty-two (78%) patients had grade 1 or 2 follicular lymphoma, and six patients (21%) had small lymphocytic lymphoma. The median number of prior chemotherapy regimens was 1 (range, 1-3). Objective responses occurred in 16 patients (57%); nine patients (32%) achieved a complete remission with a median duration of 32 months (range 4-84+ months), and seven patients (25%) had a partial remission. Grade 3 and 4 toxicities included neutropenia (72%), neutropenic fever (34%), infection (13%), mucositis (7%), and neuropathy (3%). The combination of fludarabine and paclitaxel has clinical activity in patients with recurrent low-grade NHL.

Rituximab-mediated sensitization of B-non-Hodgkin's lymphoma (NHL) to cytotoxicity induced by paclitaxel, gemcitabine, and vinorelbine

Non-Hodgkin's lymphoma (NHL) responds initially to chemotherapy, however, the disease often relapses and acquires a chemoresistant phenotype. Third line treatment options such as paclitaxel, gemcitabine, and vinorelbine have been tried in patients with refractory or relapsed NHL with antilymphoma activity. Currently, rituximab (anti-CD20) has been approved for treatment of indolent NHL, with significant activity in a wide spectrum of B-cell malignancies, though a percentage of patients do not respond to rituximab treatment. Previous findings from our laboratory have demonstrated that rituximab can sensitize drug-resistant NHL B-lymphoma in vitro to some chemotherapeutic drugs. Hence, in this study, we examined the effect of combination treatment of rituximab and the drugs paclitaxel, gemcitabine, and vinorelbine on various NHL cell lines. Our findings indicate that pretreatment of NHL tumor cells with rituximab sensitizes drug-resistant NHL tumor cells to drug-mediated cytotoxicity. These findings suggest the potential clinical application of combination treatments of rituximab and paclitaxel, gemcitabine or vinorelbine in the treatment of drug/rituximab refractory non-Hodgkin's lymphoma.