EMACO for treatment of gestational trophoblastic neoplasia: A multinational multicenter study.

OBJECTIVE: To investigate the efficacy and toxicity of etoposide, methotrexate, actinomycin D alternating with cyclophosphamide, and vincristine (EMACO) for treatment of gestational trophoblastic neoplasia, and for factors independently associated with EMACO resistance and disease-specific death in an international cohort. METHODS: Medical records of GTN patients who received EMACO during 1986-2019 from gestational trophoblastic disease centers from four countries including the USA, Thailand, Hungary, and Brazil, were retrospectively reviewed. Among 335 GTN patients, 266 patients who received EMACO as primary chemotherapy were included in the primary treatment group, and 69 patients who received EMACO after relapse/resistance to single-agent chemotherapy were included in the prior treatment group. RESULTS: Three-quarters (76.1%) of all patients achieved remission, and the survival rate was 89%. The prior treatment group had better outcomes than the primary treatment group relative to remission rate (87.0% vs. 73.3%, p = 0.014) and number of EMACO cycles to achieve remission (3 vs. 6 cycles, p < 0.001). Sustained remission increased to 87.2% in EMACO-resistant patients treated with later-line chemotherapy. Number of metastatic organs ≥2 (adjusted odds ratio [aOR]: 2.33, p = 0.049) was the only independent predictor of EMACO resistance among overall patients. Interval from index pregnancy ≥7 months (aOR: 4.34, p = 0.001), and pretreatment hCG >100,000 IU/L (aOR: 2.85, p = 0.028) were independent predictors of EMACO resistance in the high-risk subgroup. The only factor independently associated with disease-specific death was EMACO resistance (aOR: 176.04, p < 0.001). CONCLUSIONS: EMACO is an effective treatment for GTN. Number of metastatic organs and EMACO resistance were the independent predictors of EMACO resistance and disease-specific death, respectively.