Efficacy, side effects and blood concentration monitoring of high-dose methotrexate in treatment of 180 children with acute lymphoblastic leukemia / 中国实验血液学杂志

ABSTRACT

This study was purposed to investigate the effects of high-dose methotrexate (HD-MTX)-CF + VDT protocol on pediatric acute lymphoblastic leukemia (ALL) by means of retrospective analysis. MTX plasma concentration was dynamically detected and evaluated so as to avoid or reduce the side effects of HD-MTX, and adjust the time and dosage of calcium folinate (CF) or carry out the plasma exchange as occasion requires. Totally 180 cases of ALL were enrolled in this study, and received 380 administration of HD-MTX-CF + VDT protocol, including 122 patients with induction therapy as well as 58 cases during maintenance therapy, among which 68 cases were defined as low risk, 80 cases as middle risk and 32 cases as high risk. 2.0 g/m(2) MTX, 3.0 g/m(2) MTX, and 5.0 g/m(2) MTX were individually used according to low risk, middle risk or T immunohistochemical expression. The results indicated that 36.3% cases showed the side-effects of HD-MTX including mucocutaneous lesions, gastrointestinal reaction, hepatic dysfunction, renal damage, fever, myelosuppression, cardiotoxicity, infection and allergic response. All of these side effects were reversible through treatment. The elimination delay of MTX occurred in 110 cases, out of which 3 cases got MTX concentration > 10 µmol/L at 24 hours, 50 cases > 1.0 µmol/L at 44 hours, the remaining 57 cases > 0.1 µmol/L at 68 hours. CF dosage was adjusted according to the concentration of MTX until it was less than 0.1 µmol/L. 1 case had renal interstitial inflammation and acute renal failure, but finally he was cured. No patients received plasma exchange or died. It is concluded that the extramedullary leukemia control protocol, in which MTX is main drug, is effective therapy for obtaining long-term remission and event-free survival rate in ALL patients, but the side effects and risks increase along with the increase of MTX dose. The metabolic level of HD-MTX has found to be obvious individual, so the dynamic monitoring of MTX concentration in plasma and administration of proper dosage of CF are important factors for HD-MTX protocol application in ALL patients.