Treatment of High-Risk Gestational Trophoblastic Neoplasia

Clinical Characteristics and Prognostic Factors in Patients with Gestational Trophoblastic Neoplasia: A Single-Center Study Comparing Ultra-High-Risk and Other Risk Groups

Objective: To evaluate treatment outcomes and prognostic factors in patients with ultra-high-risk gestational trophoblastic neoplasia (GTN) compared to those with low-risk and high-risk GTN. Methods: A retrospective review of medical records was conducted for GTN patients treated at Chiang Mai University Hospital, Chiang Mai, Thailand, between January 1999 and December 2019. Overall and risk-specific survival rates were estimated using the Kaplan-Meier method, and prognostic factors were analyzed through univariate and multivariate analyses. Results: During the study period, 160 patients with GTN were identified, including 98 (61.2%) classified as low-risk, 31 (19.4%) as high-risk, and 31 (19.4%) as ultra-high-risk. One patient in the low-risk group and one in the high-risk group underwent hysterectomy without adjuvant chemotherapy due to spontaneous regression of serum β-hCG (human chorionic gonadotropin). Additionally, one patient with ultra-high-risk GTN died before receiving chemotherapy. Among the 97 low-risk GTN patients, 80 (82.5%) were treated with either single-agent methotrexate or actinomycin D. Among the 30 high-risk GTN patients, 20 (66.7%) received EMA/CO (etoposide, methotrexate, actinomycin D, cyclophosphamide, and vincristine) as first-line chemotherapy, while 24 (80%) of the 30 ultra-high-risk GTN patients received EMA/CO as first-line treatment. Following first-line chemotherapy and/or salvage treatment, patients with ultra-high-risk GTN had significantly worse outcomes compared with those with low- and high-risk GTN, with remission rates of 63.3%, 96.9%, and 80.0%, respectively (p < 0.01). The five-year overall survival rate for patients with ultra-high-risk GTN was significantly lower than that for patients with low- and high-risk GTN (56% vs. 96% and 80%, respectively; p < 0.001). On multivariable analysis, significant prognostic factors included antecedent term pregnancy (hazard ratio [HR] = 11.50; 95% confidence interval [CI], 3.56-37.22; p < 0.01) and brain metastasis (HR = 4.61; 95% CI, 1.73-12.28; p < 0.01). Conclusions: Ultra-high-risk GTN accounts for only a small proportion of GTN cases but it is associated with poor survival rate and responsible for the majority of GTN-related deaths. Antecedent term pregnancy and brain metastasis were identified as significant prognostic factors.

Pembrolizumab in gestational trophoblastic neoplasia: Systematic review and meta-analysis with sub-group analysis of potential prognostic factors

OBJECTIVE

To assess the performance of pembrolizumab for the treatment of Gestational Trophoblastic Neoplasia (GTN).

METHODS

The Medical Subject Headings related to immunotherapy/pembrolizumab and GTN were used alone or in combination to retrieve relevant articles. The authors searched in EMBASE, MEDLINE/PubMed, Elsevier's Scopus, and Web of Science until November/2024. The authors included any randomized controlled trials, cohort studies, case series, and case reports focusing on pembrolizumab treatment in GTN. Meta-analysis of proportions was carried out employing a random-effects model. The meta-analysis employed the inverse variance method, with the arcsine link function for the analysis of proportional data. All analyses were performed using Stata 18. For all analyses, a p-value < 0.05 indicated statistical significance. This study was registered on PROSPERO (CRD42023493329).

RESULTS

A total of 550 studies were identified after a literature search among which 15 original studies were included in the systematic review and in the meta-analysis. Pembrolizumab induced complete sustained remission in 71.59% (95% CI 53.27‒84.78%; I2 = 0.00%, H2 = 1.00, p = 0.90) of cases. The subgroups meta-analysis showed pembrolizumab had similar performance, regardless of age (< 40 vs. ≥ 40-years-old, p = 0.38), GTN histopathology (Placental Site Trophoblastic Tumor [PSTT], Epithelioid Trophoblastic Tumor [ETT]/noninvasive mole/others versus invasive mole/choriocarcinoma, p = 0.48), time from diagnosis to the beginning of immunotherapy (< 4 vs. ≥ 4-years, p = 0.84), pembrolizumab combined with chemotherapy (yes vs. no, p = 0.66).

CONCLUSIONS

Pembrolizumab seems an effective treatment for patients with high-risk GTN with chemoresistant or relapsed disease, including cases of PSTT/ETT, notwithstanding patient age, time to initiate immunotherapy and whether or not it was associated with chemotherapy.