Infectious complications of chronic lymphocytic leukemia.

Infectious complications continue to be one of the major causes of morbidity and mortality in patients with chronic lymphocytic leukemia (CLL). The pathogenesis of infections in these patients is multifactorial. Hypogammaglobulinemia is an important predisposing factor for infection in patients with early-stage disease and for those treated with conventional alkylating agents. However, the proportion of patients treated with purine analogs and monoclonal antibodies such as rituximab and alemtuzumab is increasing. As a result of this therapy, these patients often experience profound and sustained T-cell immunodeficiency. Consequently, the spectrum of organisms causing infections in these patients is changing from common bacterial organisms to less common opportunistic pathogens such as Pneumocystis, Listeria, mycobacteria, herpesviruses, and Candida. This review focuses on the pathogenesis and risk factors for infections in patients with CLL, the spectrum of infectious organisms associated with the newer agents, and the management of these infections with an emphasis on prophylaxis and vaccination strategies.

Hematopoietic recovery after unrelated umbilical cord-blood allogeneic transplantation in adults treated with in vivo stem cell factor (R-MetHuSCF) and filgrastim administration.

Transplantation with unrelated umbilical cord blood (UCB) is marked by delayed hematologic recovery. This report summarizes two adults with chronic myelogenous leukemia (CML), who received myeloablative conditioning followed by infusion of a non-expanded single UCB graft. These CML patients were enrolled in a clinical trial incorporating concomitant in vivo administration of stem cell factor (R-MetHuSCF) and filgrastim from day of UCB infusion until attained hematopoietic recovery. Each patient engrafted fully with donor UCB, with days to absolute neutrophil count (ANC) >500/microl being 13 and 29 days, respectively. Both patients remain in cytogenetic remission at 28 months follow-up. 'In vivo UCB expansion' with administration of concomitant R-MetHuSCF and filgrastim may facilitate prompt hematologic engraftment.

Prognostication of diffuse large B-cell lymphoma in the rituximab era.

Predicting the prognosis of patients diagnosed with diffuse large B-cell lymphoma (DLBCL) has been a moving target over the last several years. While earlier prognostic models relied mainly on such clinical variables as age, stage of disease, and performance status, it has become evident from gene-expression microarray studies that DLBCL is a heterogeneous disease in terms of molecular pathogenesis and cell of origin. Despite providing considerable insight into disease biology, these techniques are not widely available and are, at least at present, not applicable to routine clinical practice. Furthermore, older prognostic models need to be revalidated and modified as improved therapeutic options become available. In this review, we discuss pertinent studies on individual biomarkers and pattern-based biomarker models, with an emphasis on markers evaluated in patients treated with rituximab-containing chemotherapy. We also discuss recent and ongoing therapeutic trials using drugs that target molecular markers and pathways involved in the pathogenesis of DLBCL or those that adversely influence prognosis. The ultimate goal of these efforts is to refine prognostication of DLBCL using widely available, reproducible, and consistently predictive biomarker models applicable to currently used chemoimmunotherapy, and to create a pathophysiologically based framework for the rational design of individually tailored therapy.

High-dose carmustine, etoposide, and cisplatin for autologous stem cell transplantation with or without involved-field radiation for relapsed/refractory lymphoma: an effective regimen with low morbidity and mortality.

Over a 10-year period (January 1993 to October 2002), 101 relapsed or refractory non-Hodgkin lymphoma patients were treated at our center with high-dose chemotherapy and autologous transplantation. The median patient age was 54 years (range, 25-70 years). Thirty-two patients had indolent (low-grade), 42 had aggressive (intermediate-grade), and 27 had very aggressive (high-grade) non-Hodgkin lymphoma. Thirty-six patients had primary refractory disease, 20 had a chemoresistant relapse, 35 patients had a chemosensitive relapse, and 10 patients were "initial high risk" patients. The median number of prior chemotherapy regimens was 2 (range, 1-5). The preparative regimen (BEP) was bischloroethylnitrosourea (BCNU) 600 mg/m 2 , etoposide 2400 mg/m 2 , and Platinol (cisplatin) 200 mg/m 2 given intravenously over 5 days. Within 3 weeks before transplantation, 70 patients received involved-field radiotherapy (IFR) 20 Gy to sites of currently active (>2 cm) or prior bulky (>5 cm) disease. Most patients (n = 93) received mobilized peripheral blood stem cells (median CD34 + cell dose, 6.7 x 10 6 /kg). Median neutrophil (>500/microL) and platelet (>20 000/microL, untransfused) recoveries were 11 days (range, 7-19 days) and 14 days (range, 7-36 days), respectively. At a median follow-up of 41 months (range, 4 to 118 months) for survivors, Kaplan-Meier 5-year probabilities of overall survival (OS) and disease-free survival (DFS) were 58.6% and 51.1%, respectively. Four patients (4%) died within 30 days of stem cell infusion (1 pulmonary embolism, 2 septicemias with multiorgan failure, and 1 progressive lymphoma). Two patients (2%) developed interstitial pneumonitis most likely secondary to high-dose BCNU. Three cases (3%) of secondary acute myelogenous leukemia occurred. On multivariate analysis, age (<60 or > or =60 years), histologic grade (low versus intermediate or high), the use of IFR, and chemotherapy response at baseline did not affect OS or DFS. Of 70 patients given IFR, 27 relapsed: 10 (37%) within and 17 (63%) outside the radiation field. The use of IFR did not affect either OS or DFS, probably because IFR was offered to patients with bulky or chemoresistant disease. BEP with or without IFR is a highly effective and well-tolerated regimen in the relapsed/refractory lymphoma setting. It has low morbidity and transplant-related mortality and a low incidence (3%) of posttransplantation malignancy.

Cancer gene therapy: scientific basis.

Gene therapy of cancer has been one of the most exciting and elusive areas of therapeutic research in the past decade. Critical developments have occurred in gene therapy targeting cancer cells, cancer vasculature, the immune system, and the bone marrow, itself often the target for severe toxicity from therapeutic agents. We review some recent developments in the field. In each instance, clear preclinical models validated the therapeutic approach and efforts have been made to evaluate the target impact in both preclinical and early clinical trials. Although no cures can consistently be expected from today's cancer gene therapy, the rapid progress may imply that such cures are a few short years away.