SINGLE-AGENT METHOTREXATE CHEMOTHERAPY FOR THE TREATMENT OF NONMETASTATIC GESTATIONAL TROPHOBLASTIC TUMORS

OBJECTIVE: Our purpose was to evaluate the efficacy and toxicity of si ngle-agent methotrexate chemotherapy and to identify factors associate d with chemotherapy resistance in patients with nonmetastatic gestatio nal trophoblastic tumors. STUDY DESIGN: A total of 337 patients with n onmetastatic gestational trophoblastic tumors (choriocarcinoma and inv asive mole) received treatment at the Brewer Trophoblastic Disease Cen ter of Northwestern University Medical School from 1962 through 1990. Of the 337 patients, 253 (75.0%) were treated initially with single-ag ent methotrexate 0.4 mg/kg intravenously daily for 5 days per treatmen t course repeated every 14 days. RESULTS: All 337 patients with nonmet astatic gestational trophoblastic tumors were cured. Of the 253 patien ts initially treated with methotrexate, resistance developed in 27 (10 .7%), 22 (8.7%) required a second agent (actinomycin D), 3 (1.2%) requ ired multiagent chemotherapy, and 2 (0.8%) had a hysterectomy to achie ve complete remission. Factors associated with the development of resi stance were pretreatment human chorionic gonadotropin level greater th an or equal to 50,000 mlU/ml (36%, p < 0.001), nonmolar antecedent pre gnancy (26%, p < 0.02), and clinicopathologic diagnosis of choriocarci noma (20.5%, p = 0.02). Significant methotrexate toxicity requiring a change to a second agent occurred in only 12 patients (4.7%), the most common side effect being severe stomatitis. CONCLUSIONS: In a large s eries of patients with nonmetastatic gestational trophoblastic disease , single-agent methotrexate chemotherapy proved to be an extremely wel l-tolerated and effective treatment.