Use of active detoxification methods with delayed elimination of methotrexate after high-dose infusion in a child with osteogenic sarcoma: clinical observation
This article represents clinical case presentation of delayed elimination of methotrexate (MTX) after high dose infusion at a patient of 12 years old with morphologically approved osteosarcoma of proximal metadiaphisis of left tibia. This boy received specific drug therapy in clinic of N.N. Petrov National Research Center of Oncology by EURAMOS program. Common time of excretion was increased to 144 hours and accompanied by kidney, liver and hematological toxicity of 2-4 gr. Abovementioned condition was eliminated by substitutive, infusion and symptomatic therapy. Patient was discharged in satisfactory condition on 12 day after MTX infusion. As a rule, prolonged excretion of MTX is connected with dysfunction of enzymes participating in intracellular metabolism of cytostatic. Data on pharmacokinetics and pharmacodynamics of drug which to a large extent allows to explain disturbance of excretion of MTX from blood serum discussed. Genes with mutations influencing on enzymes function and MTX metabolism, which are decreasing elimination of abovementioned drug and increasing toxicity are already known. Article represents method of application of high doses of antagonist of leucovorin antifolates (calcium folinate) and intensification of efferent therapy with plasma exchange procedures. Detailed algorithm of treatment of different complications associated with delayed excretion of MTX from blood serum proposed.