A phase II trial of aminothiadiazole in patients with mixed mesodermal tumors of the uterine corpus: A gynecologic oncology group study

Aminothiadiazole (NSC 4728) is an analog of the thiadiazoles, a group of drugs that stimulated interest because they do not cause significant myelosuppression and have a unique ability to increase uric acid production unrelated to tissue damage. Previous articles have reported results in ovarian cancer, squamous cell cervical cancer, nonsquamous cell cervical cancer, and endometrial cancer. The Gynecologic Oncology Group chose to study aminothiadiazole in patients with mixed mesodermal tumors of the uterus refractory to prior chemotherapy. Twenty-two patients were entered into this study. Eligibility required that patients had histologically confirmed measurable malignancy. Ail patients received a starting dose of aminothiadiazole of 125 mg/m(2) intravenously (30-45 min infusion) repeated at weekly intervals. All patients also took allopurinol, 300 mg orally per day, to prevent hyperuricemia. Subsequent therapy was not given unless the white blood cell count was >3,000/mu l and platelets were >100,000/mu l prior to treatment. One patient (5%) in this study had a partial response, which lasted only 1.2 months. The site of this response was a mesenteric mass. Most patients in this study had no toxicity whatsoever, and no life-threatening toxicity was seen. There were no complete responses. Aminothiadiazole in this dose schedule appears to have no utility in previously treated patients with mixed mesodermal tumors of the uterus.