Risk factors for high-dose methotrexate-induced nephrotoxicity.

High-dose methotrexate (MTX) is widely used for the treatment of hematological malignancies. Despite the application of routine supportive care measures, such as intensive fluid hydration and urine alkalinization, nephrotoxicity is still a problem. The present study aimed to evaluate the risk factors for MTX-induced nephrotoxicity. We retrospectively reviewed 88 patients who received a regimen consisting of high-dose MTX (1000 mg/m2) and cytosine arabinoside between 2006 and 2018. Nephrotoxicity (≥ grade 2) was observed in 11 patients. Nephrotoxicity was observed only in patients with a high MTX concentration. Other than the MTX concentration, the serum uric acid level and urine pH at day 1 were associated with nephrotoxicity. A multivariate analysis revealed that urine pH was an independent risk factor for MTX-induced nephrotoxicity. Urine pH < 7.0 at day 1 was a significant risk factor for nephrotoxicity (odds ratio, 8.05; 95% confidence interval 1.95-33.3) and was also a predictor of delayed MTX elimination at 72 h after injection. Among pre-treatment factors, a low serum calcium level predicted urine pH < 7.0 at day 1. In conclusion, the present study suggests that low urine pH at day 1 is an independent risk factor for MTX-induced nephrotoxicity.

Clinical significance of autologous blood transfusions in bone marrow harvest from unrelated donors.

In the Japan Marrow Donor Program (JMDP), autologous blood is collected from most unrelated bone marrow (BM) donors. We retrospectively evaluated 5772 donors who underwent BM harvest between 2010 and 2015 through the JMDP. Autologous blood was collected in 96.8% of the donors; the wastage rate was 0.6%. Allogeneic blood transfusion was not required. The mean hemoglobin (Hb) levels were 12.1 g/dL after the BM harvest (mean 891 mL) together with autologous blood transfusion (mean 596 mL). Propensity-score matching was used to adjust the backgrounds. Among donors with harvested BM of 100-400 mL, autologous blood transfusion had no impact on Hb levels or complications after BM harvest. Among donors with harvested BM of > 400 mL, more autologous blood transfusion followed by a bleeding volume of ≤ 100 mL did not confer clinical benefit to donors compared with less autologous blood transfusion followed by a bleeding volume of > 300 mL. The findings of the present study suggest that autologous blood transfusion to BM donors is excessive in terms of Hb changes and post-harvest outcomes.

CD25 as an adverse prognostic factor in elderly patients with acute myeloid leukemia.

OBJECTIVES: CD25 has been reported to be highly expressed in leukemia stem cells and correlated with adverse outcomes in young patients with acute myeloid leukemia (AML). However, the significance of CD25 expression in elderly patients with AML has not yet been investigated. METHODS: We retrospectively analyzed 154 newly diagnosed AML patients aged 60 years or over by flow cytometry. RESULTS: CD25-positive AML was characterized by high white blood cell counts, secondary AML, rare favorable karyotypes, and positivity for CD34 and CD7 antigens, compared with CD25-negative AML. CD25 positivity was significantly correlated with an inferior complete remission (CR), event-free survival (EFS), and overall survival. Multivariate analysis showed CD25 positivity to be a significant prognostic predictor of CR and EFS. A regimen of low-dose cytarabine and aclarubicin combined with granulocyte-colony-stimulating factor (CAG) led to higher CR rates in the CD25-positive AML patients than intensive chemotherapies. CD25 expression was increased at relapse and in the development of leukemic status from myelodysplastic syndrome or myeloproliferative neoplasm. DISCUSSION: An effective treatment strategy for elderly patients with CD25-positive AML has not been established. Further studies are needed to evaluate the effect of a CAG regimen and allogenic stem cell transplantation in patients. CONCLUSION: CD25 is an independent prognostic factor in elderly AML patients. Alternative therapies for CD25-positive elderly AML patients are needed.