Distribution and pharmacokinetics of methotrexate in localized chemotherapy of solid Gardner's lymphosarcoma

Pharmacokinetics and organe distribution of Methotrexate (MTX) in Gardner lymphosarcoma bearing C3H mice was investigated following two ways of drug administration: 1. intraperitoneal injection, 2. intratumoral implantation of 2-hydroxyethylmethacrylate gel with sorbed Methotrexate (localized chemotherapy). The highest level of MTX in blood appeared 2 hours after intrperitoneal injection but 7 hr after localized intratumorous application. Following intraperitoneal application the drug level in tumor reached its maximum two hours after injection; after 7 hr the drug could not be detected any longer. The localized chemotherapy led to six times higher concentration of the drug in the tumors as compared with the intraperitoneal application. This high level persisted for 17 hr and decreased moderately for 48 hr. MTX was accumulated in liver after both modes of administration with a half life 6.1 hr after intraperitoneal injection and 12.4 hr after the localized chemotherpay, respectively.