Consolidation courses in low-risk gestational trophoblastic neoplasia and relapse rate: A MITO-9 retrospective study

Objective: Methotrexate (MTX) is the gold standard treatment for gestational trophoblastic neoplasia (GTN). It is administered until negative human chorionic gonadotropin (hCG) levels, after which consolidation courses are recommended. Aim of this study was to evaluate the relationship between number of consolidation courses and relapse rate. Methods: Patients with low-risk GTN treated with first-line MTX between 1981 and 2022 in Italy were retrospectively identified. Exclusion criteria were exclusive surgical treatment, missing data on number of courses or non-standardized definitions of chemoresistance. Results: Among 435 low-risk GTN patients, 333 were eligible. A total of 224 (67.2 %) patients achieved remission after treatment with first-line MTX. Forty-one patients (17.4 %) underwent 2 consolidation courses and had no relapse; 132 (56.1 %) received 3 consolidation courses with a relapse rate of 2.2 %; 39 patients (16.5 %) received more than 3 consolidation courses with a relapse rate of 10.2 %. Ninety-five percent of patients undergoing 2 consolidation courses had a FIGO score ≤ 4. Multivariate analysis showed that number of consolidation courses is not related to disease relapse in patients scoring 0–2. Conclusions: Number of consolidation courses in low-risk GTN does not impact relapse rate. Our study demonstrates that patients with FIGO scores of 0,1 and 2 can safely receive 2 consolidation courses. Further studies should investigate the appropriate number of consolidation courses in patients with higher scores.