The role of low-dose methotrexate and folinic acid in gestational trophoblastic tumours (GTT).

Between 1964 and 1986, 487 patients with gestational trophoblastic tumour (GTT) were treated with methotrexate and folinic acid. The patients comprise two groups: between 1964 and 1974, 126 patients were treated but were not systematically stratified using a prognostic score before the start of treatment. These patients formed part of the 317 women who were analysed to identify a number of prognostic variables (Bagshawe 1976). Retrospective analysis of these 126 patients using these prognostic factors showed that in the true low-risk group 85/88 (96%) are alive while 20/22 (91%) of the medium-risk group and only 5/16 (31%) of the high-risk group are alive. Overall the survival was 110/126 (87%) with a minimum follow-up of 14 years. From 1974 all patients were stratified on admission into prognostic groups. Of the true low-risk patients 347/348 survived (99.7%); 13 patients were underscored and treated as low risk when they should have been treated as medium risk, 12 (92%) of these are alive, but nine (69%) needed to change treatment because of drug resistance. While the overall survival in the 1974-1986 group was 359/361 (99%) with a minimum follow-up of 16 months, the survival in all patients (1964-1986) was 469/487 (96%). Although the survival in these patients is excellent it should be noted that 69/348 (20%) low-risk patients had to change treatment because of the development of drug resistance, and a further 23 (6%) needed to change treatment because of drug-induced toxicity.(ABSTRACT TRUNCATED AT 250 WORDS)