Abstract

Five patients, three high risk and two medium risk, were allocated to a high dose methotrexate regimen. Surviving fractions of hCG-producing cells in high dose methotrexate were a factor of 3–10 times lower than the surviving cell fractions in the low dose regimen, indicating a biphasic dose-response relation for methotrexate. Medium risk patients were found to have an unacceptably high recurrence rate after methotrexate actinomycin-D therapy and should be treated with more intensive chemotherapy. It is recommended that drug dose should be corrected for body-volume in low risk regimes, to avoid drug resistance developing because of increased treatment time.