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Conventional transplants, which are generally not perfomed onpeople over age 60 or others who are medically unfit, use highdoses of total-body irradiation and potent chemotherapy toeliminate leukemic cells. The intense treatment destroys the bloodand immune system and is fatal unless the patient is rescued byinfusion of donor bone marrow or stem cells isolated fromperipheral blood. The mini-transplant, in contrast, relies on the ability of donorimmune cells to target and destroy the cancer without the need forhigh-dose chemotherapy and radiation. Instead, low-dose radiationand chemotherapy is used to suppress the immune system rather thandestroy it. This helps the body accept the donor stem cells, whichthen go to work to attack cancer cells called thegraft-vs.-leukemia effect and rebuild the immune system. The study involved 372 patients ages 60 to 75 who were enrolled inprospective clinical trials between 1998 and 2008 at 18collaborating U.S. and European cancer centers known as the"Seattle Consortium." All patients at these centers were treatedwith the same regimen, which was developed in Seattle. The patientsin the study were treated for acute and chronic leukemia, lymphoma, multiple myeloma , myelodysplastic syndromes (which can progress to acute myeloidleukemia if not treated) and myeloproliferative diseases such aschronic myelogenous leukemia. In addition to survival and the impact of comorbid conditions, thestudy examined rates of relapse, hospitalization, acute and chronicgraft-vs.-host disease (GVHD, the most common side effect oftransplantation), and the toxicity of the treatment to internalorgans. For example, two-thirds of patients five years after theirtransplants who were affected by chronic GVHD had completeresolution of their symptoms and were able to discontinueimmunosuppressive medications after a median time of 2.5 years fromdiagnosis. This was comparable to the duration reported by previousstudies on younger patients who were treated with high-doseradiation and chemotherapy. Half of the patients never requiredhospitalization after transplant. "These findings, together with the normal to near-normalperformance status of surviving patients, should help allayreluctance in entering older patients with hematologic cancers onnonmyeloablative transplantation protocols," Sorror said. The lackof a matched sibling donor also should no longer be a limitationgiven that transplants with matched unrelated donor grafts hadcomparable outcomes, he said. Disease relapse risks and comorbidities, but not increasing age,were associated with worse outcomes. The Seattle Consortiuminvestigators continue to explore novel approaches to be combinedwith the mini-transplant to reduce the relapse rate, particularlyamong patients with more aggressive blood cancers. Sorror and colleagues previously developed and published theHematopoietic Cell Transplant-specific Comorbidity Index (HCT-CI)by studying the associations between single comorbidities (such as diabetes , heart diseases, etc) and mortality after a stem cell transplant. Laboratory and organ-function values were used to refine thedefinition of comorbidities. Based on extensive statisticalanalyses, scores were given to each of 17 different comorbiditiesthat constitute the HCT-CI based on their correlation with accurateforecast of patient outcomes. "The use of the HCT-CI in this study facilitated capturing theimportant role of comorbidities in defining survival of olderpatients. Ongoing research is focused on understanding the biologybehind the association between pre-transplant comorbidities andpost-transplant morbidity and mortality," he said. The authors noted that 20 percent of the U.S. population will be 65or older by 2030, and that increases of up to 77 percent in thenumber of newly diagnosed blood cancers among this population areexpected to occur in the next two decades. Such malignancies aremainly diseases of the elderly. Yet, only 12 percent of patientswho were treated with a transplant between 2004 and 2008 in U.S.institutions were over age 60 and a previous study suggested thatonly 26 percent of patients with acute myeloid leukemia weretreated with a transplant, according to results reported by theCenter of International Blood and Marrow Transplantation Research. "These statistics clearly highlight the reluctance of providers inoffering allogeneic stem cell transplantation to the elderly,"Sorror said. "Little is known about the reasons behind the lowreferral rate of older patients to transplant or howmini-transplant outcomes compare to those of conventionaltherapies. We are initiating a multicenter study designed to followpatients from the time of diagnosis to answer both questions."Sorror said. The National Institutes of Health and the Leukemia &Lymphoma Society funded the research. Additional References Citations. We are high quality suppliers, our products such as Mobile Security DVR Manufacturer , Vehicle Video Recorders Manufacturer for oversee buyer. To know more, please visits Mobile Security DVR.
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