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César O Freytes

Publications and source records attributed to César O Freytes.

6 recordsLinked to original sources
PubMed2006

Autologous or allogeneic stem cell transplantation in patients with Waldenstrom's macroglobulinemia.

The role of hematopoietic stem cell transplantation (SCT) in Waldenstrom's macroglobulinemia (WM) has not been extensively studied. To determine the potential for long-term disease control using SCT in WM, we performed a retrospective review of 36 patients with WM who received autologous (n = 10) or allogeneic (n = 26) SCT and were reported to the Center for International Blood and Marrow Transplant Research between 1986 and 2002. The following outcomes were described: nonrelapse mortality (NRM), relapse, progression-free survival (PFS), and overall survival (OS). Median age at the time of SCT was 51 years (range, 30-76 years), and median time from initial treatment to SCT was 29 months (range, 2-198 months). A total of 78% of the patients had 2 or more previous chemotherapy regimens, and 52% had disease resistant to salvage chemotherapy. In the allogeneic SCT group, 58% of the patients received myeloablative conditioning regimens containing total body irradiation (TBI), and of the allograft recipients, 19% received nonmyeloablative/reduced-intensity conditioning. After a median follow-up of 65 months, 15 of the 36 patients (42%) are alive. Primary disease accounted for 29% of the deaths in the allogeneic SCT group and 25% of the deaths in the autologous SCT group. The relapse rate at 3 years was 29% (95% confidence interval [CI], 14%-48%) in the allogeneic group and 24% (95% CI, 4%-54%) in the autologous group. PFS at 3 years was 31% (95% CI, 14%-50%) in the allogeneic group and 65% (95% CI, 32%-91%) in the autologous group; OS was 46% (95% CI, 27%-65%) in the allogeneic group and 70% (95% CI, 40%-93%) in the autologous group. NRM at 3 years was 40% (95% CI, 23%-59%) in the allogeneic group and 11% (95% CI, 0-36%) in the autologous group. Autologous SCT is a safe and feasible treatment option for patients with WM, especially for those who present with adverse prognostic factors. Allogeneic SCT carries a much higher (40%) risk of NRM and should not be considered outside the context of a clinical trial.

Adult↗
PubMed2005

Differences in characteristics of US hematopoietic stem cell transplantation centers by proportion of racial or ethnic minorities.

Racial or ethnic minorities with leukemia who receive HLA-identical sibling hematopoietic stem cell transplants (HSCTs) are reported to have worse survival when compared with whites. Characteristics of US HSCT centers according to the proportion of ethnic minorities who undergo transplantation were compared to explore systematic differences among centers; the association with 100-day mortality was evaluated to determine whether center factors may explain the observed discrepant survival among ethnic minorities. One hundred sixteen US transplantation centers that performed HLA-identical sibling transplantations for leukemia were analyzed. We compared physician and health care provider staffing, transplantation unit procedure and resources, and medical center organization according to the volume procedure ratio of ethnic minorities who underwent transplantation and also according to the ratio of Hispanics who underwent transplantation. Centers that performed transplantation in a higher proportion of ethnic minorities were more likely to perform fewer transplantations per year, to have fewer devoted transplant beds, to be in an urban setting, to have a lower physician to patient volume ratio, and to follow up survivors 1 year after transplantation. Centers that performed transplantation in a higher proportion of Hispanics were more likely to perform fewer transplantations per year and to have fewer devoted transplantation beds, were less likely to perform outpatient transplantations, were more likely to be in an urban setting, and were less likely to have posttransplantation immunization protocols. Observed differences in center factors were not associated with 100-day mortality after adjustment for disease severity. Our results suggest that the inferior survival reported in ethnic minorities after HSCT may not be readily explained by center effects.

Disease-Free Survival↗
PubMed2004

Myeloablative allogeneic hematopoietic stem cell transplantation in patients who experience relapse after autologous stem cell transplantation for lymphoma: a report of the International Bone Marrow Transplant Registry.

Myeloablative allogeneic hematopoietic stem cell transplantation (allo-HSCT) is increasingly used in patients with lymphoma who experience disease relapse after autologous hematopoietic stem cell transplantation (auto-HSCT) because the allograft is tumor free and may induce a graft-versus-tumor effect. We analyzed 114 patients treated with this approach from 1990 to 1999 to assess disease progression, progression-free survival (PFS), and overall survival (OS). Cumulative incidence of disease progression at 3 years was 52%, whereas treatment-related mortality was 22%, lower than previously reported. Three-year probabilities of OS and PFS were 33% and 25%, respectively. With prolonged follow-up, however, nearly all patients experienced disease progression, and 5-year probabilities were 24% and 5%, respectively. Complete remission at the time of allo-HSCT and use of total body irradiation (TBI) in patients with non-Hodgkin lymphoma (NHL) were associated with lower rates of disease progression and higher rates of OS. In summary, allo-HSCT is feasible for patients with lymphoma who have relapses after auto-HSCT and can result in prolonged survival for some, but it is usually not curative. Most likely to benefit are patients who have HLA-matched sibling donors, are in remission, and have good performance status.

Adolescent↗
PubMed2004

Biofilm: the microbial "bunker" for intravascular catheter-related infection.

Catheter-related infection in cancer patients remains an important health-care problem with major financial implications. During the last few years a better understanding of the pathogenesis of catheter-related infections and the interaction between microorganisms and catheter surfaces has emerged. Recently the influence of biofilm formation in catheter-related infections has been established. The development of biofilm by the colonizing microbes permits attachment of the organisms to the vascular access device and confers resistance to antibiotics and host defense mechanisms. Strategies to overcome the development of biofilm are being developed to prevent catheter- and other medical device-related infections.

Bacterial Adhesion↗
PubMed2003

Thromboembolic complications related to indwelling central venous catheters in children.

PURPOSE OF REVIEW: Thrombosis is one of the most frequent complications of indwelling central venous catheters. During the past year, new information has emerged regarding the incidence and predisposing factors of thromboembolic complications of indwelling central venous catheters. Because indwelling central venous catheters are widely used, it is important to be aware of new information regarding thromboembolic complications of these devices. RECENT FINDINGS: Recent studies have better defined the risks of thromboembolic complications in patients with cancer with indwelling central venous catheters. Acquired hypercoagulable disorders such as heparin-induced thrombocytopenia, antiphospholipid syndrome, and therapy with asparaginase are associated with thromboembolic disorders in patients with indwelling central venous catheters. Studies analyzing the association between inherited hypercoagulable disorders and thrombosis have shown conflicting results. Preliminary studies suggest that low molecular weight heparins could have a role in the prevention of catheter-related thromboembolic disorders. Nevertheless, larger prospective studies will be necessary to determine the role of anticoagulants in the prevention of thromboembolic disorders in patients with cancer with indwelling central venous catheters. SUMMARY: Recent reports will facilitate the evaluation and risk assessment of children with cancer who have indwelling central venous catheters. Despite these advances, large, controlled studies focusing on specific populations of patients, such as children, should be undertaken to determine the true performance and optimal use of indwelling central venous catheters. Future studies should also address better ways to prevent catheter-related thrombosis and infection.

Catheterization, Central Venous↗