The role of obesity on autologous bone marrow transplant and post-transplant outcomes

Background/Aim: Autologous hematopoietic cell transplantation (AutoHCT), administered at high doses, has improved survival rates among patients with refractory or recurrent lymphoma and multiple myeloma (MM). However, inconsistencies in defining obesity, varying body weight ranges, and heterogeneous patient populations have been examined. Some researchers have hypothesized that significantly overweight patients face a higher risk of transplant-related complications. This study investigates the association between body mass index (BMI), obesity, and autologous peripheral stem cell mobilization. Methods: A retrospective evaluation of data from 180 patients who underwent peripheral stem cell mobilization at our clinic between 2014 and 2020 was conducted. Excluding patients under 18 years of age, the primary objective was to assess how BMI influences autologous transplant outcomes and mortality. This retrospective cohort study aimed to determine whether obesity constitutes an independent risk factor for autologous bone marrow transplantation. Results: Among the patients, the most prevalent diagnosis (47.2%) was MM, with notable differences in incidence rates across BMI categories (P=0.039). Obesity and overweight were associated with a higher incidence of MM (47.2%), whereas normal and underweight individuals had predominantly been diagnosed with DLBCL (44.2%). Significant differences in CD34 cell counts were observed among BMI groups (P=0.033). Overweight and obese individuals exhibited lower CD34 cell counts than underweight/normal groups (P=0.033). The treatment group showed significantly higher CD34 cell counts than the G-CSF alone group (P=0.046). Female gender (P=0.022), PLT engraftment (P=0.024), post-chemo-mobilization hospital-stay duration (P=0.019), and G-CSF count were identified as mortality risk factors (P=0.017). Conclusions: This investigation found no adverse correlation between mortality and weight among patients with various hematological malignancies undergoing AutoHCT. Obesity alone should not be a contraindication for proceeding with AutoHCT in clinically warranted hematological malignancy treatment, as no significant survival differences were observed among overweight, obese, and normal-weight individuals.