Pulse actinomycin D as first-line treatment of low-risk post-molar non-choriocarcinoma gestational trophoblastic neoplasia

Background: Little data exists predicting the resistance to actinomycin D (Act-D) single-agent for gestational trophoblastic neoplasia (GTN). The objective was to determine the overall success of pulse Act-D and the factors predictive of resistance to pulse Act-D in the treatment of low-risk, non-choriocarcinoma post-molar GTN. Methods: From January 2013 to October 2016, according to the FIGO criteria for the diagnosis of post-molar disease and the FIGO risk-factor scoring system for GTN, a total of 135 patients with post-molar non-choriocarcinoma GTN who were chemotherapy-naive with a FIGO score < 7 were treated with single-agent pulse Act-D as a first-line regimen, in Peking Union Medical College Hospital. The pulse Act-D regimen is defined as 1.25 mg/m(2) (max 2 mg) IV push every other week. All patients were followed until May 2017. Epidemiological and clinical data were compared between patients with remission and resistance to Act-D to determine predictive factors by univariate and multivariate analysis. Results: Ninety-six of 135 patients (71.1%) achieved complete remission after first-line chemotherapy of pulse Act-D. In multivariate analysis, existing invasive uterine lesions observed by pre-chemotherapy transvaginal ultrasound (odds ratio [OR] 7.5, 95% confidence intervals [CI] 2.7-20.8), FIGO score >= 5 (OR 15.2, 95% CI 1.5-156.1) and pre-chemotherapy levels of beta-hCG >= 4000 IU/L (OR 3.1, 95% CI 1.2-8.3) were independent high-risk factors predicting resistance to pulse Act-D as single-agent chemotherapy. During follow-up, no relapse, treatment-associated serious adverse events, or death occurred. Conclusions: As first-line chemotherapy, pulse Act-D was effective and tolerable for patients with low-risk post-molar non-choriocarcinoma. Existing invasive uterine lesions observed by pre-chemotherapy transvaginal ultrasound, a FIGO score >= 5, and pre-chemotherapy levels of beta-hCG >= 4000 IU/L were independent factors for resistance to pulse Act-D.