Obesity Does Not Preclude Safe and Effective Myeloablative Hematopoietic Cell Transplantation (HCT) for Acute Myelogenous Leukemia (AML) in Adults

Abstract

The incidence of excessive adiposity is increasing worldwide and is associated with numerous adverse health outcomes. We compared outcomes by body mass index (BMI) for adult patients with acute myeloid leukemia (AML) who underwent autologous (auto, n=373), related donor (RD, n=2041), or unrelated donor (URD, n=1801) allogeneic myeloablative hematopoietic cell transplantation (HCT) using marrow or peripheral blood stem cells reported to the Center for International Blood and Marrow Transplant Research (CIBMTR) from 1995-2004. Four weight groups by BMI (kg/m2) were defined: underweight < 18; normal 18 – 25; overweight >25 – 30; and obese > 30. Multivariable analysis referenced to the normal weight group showed an increased risk of death for underweight patients in the RD group (RR, 1.92; 95% CI, 1.28-2.89; P = 0.002) but not in the URD group. There were no other differences in outcomes among the other weight groups within the other HCT groups. Overweight and obese patients enjoyed a modest decrease in relapse incidence, though this did not translate into a survival benefit. Small numbers of patients limit the ability to better characterize the adverse outcomes seen in the underweight RD but not the underweight URD allogeneic HCT patients. Obesity alone should not be considered a barrier to HCT.

Outcomes after autologous SCT in lymphoma patients grouped by weight

“…Our relapse and OS results were consistent with other large retrospective studies in AML and lymphoma patients undergoing auto-SCT. 8,9 Although both of these studies included over 4000 patients, the patient populations were from multiple institutions that varied in conditioning regimens, chemotherapy doses and dosing weight calculations. Despite this, these two studies and ours have shown multiple factors that contribute to relapse and OS outcomes, none of which identified obesity as a prognostic factor impacting patient outcomes.…”

“…8,9 A subgroup analysis was performed comparing the underweight and normal weight patients to assess heterogeneity. Having found no difference in relapse or survival outcomes, and given the limited number of underweight patients, combining underweight and normal weight patients likely did not have an impact on the overall outcomes or conclusions of our study.…”

“…Studies investigating outcomes of overweight and obese patients undergoing SCT have reported mixed results, leading to controversy about the optimal dosing strategy in SCT. [7][8][9] Citing insufficient evidence to draw conclusive recommendations, the American Society of Blood and Marrow Transplant Practice Guideline Committee recently published a literature review in an effort to help guide chemotherapy dosing in obese patients undergoing SCT. 10 The purpose of this single-center, retrospective study was to investigate safety and efficacy outcomes among normal/ underweight, overweight and obese patients who underwent auto-SCT and received a standardized chemotherapy conditioning regimen of BU, CY and etoposide dosed using adjusted body weight.…”

Severe weight loss in 3 months after allogeneic hematopoietic SCT was associated with an increased risk of subsequent non-relapse mortality

“…6 Even though oral caloric intake often recovers spontaneously, time taken for recovery is usually long and patients often experience significant weight loss. 7,8 Even though several studies assessed the impact of body mass index (BMI) before allogeneic HSCT, [9][10][11] there are limited data about the nutritional status of outpatients after allogeneic HSCT because the practice of screening of nutritional status is still rarely performed. Nutritional screening aims to identify patients who are malnourished or at risk of malnutrition.…”

Impact of pretransplant body mass index on the clinical outcome after allogeneic hematopoietic SCT

“…A large retrospective study from the Center for International Blood and Marrow Transplant Research (CIBMTR) showed that the probability of OS in patients with low BMI (BMI o 18.5 kg/m 2 ) was inferior to that in patients with a normal BMI in patients who received stem cells from either related or unrelated donors, mainly because of the increased risk of relapse. 4 A limitation of this CIBMTR study was the limited number of patients with low BMI (32 of 2041 patients (1.6%) who received related HSCT and 33 of 1801 patients (1.8%) who received unrelated HSCT). We previously reported that there was a trend toward an increased risk of acute GVHD and NRM in patients with high BMI, and the risk of relapse was higher in patients with low BMI using registry data from the Japanese Marrow Donor Program.…”