Clinical utility of a tumor-naïve circulating tumor DNA (ctDNA) test to predict outcomes in patients with advanced testicular germ cell tumors.
Year: 2025
Type: conference-abstract
Abstract: 5032 Background: Serum tumor markers (STM) used in the management of Testicular Germ Cell Tumors (TGCT) lack sufficient specificity and are not altered in up to 60% of patients (pts). We evaluated the clinical utility of a tumor-naïve ctDNA test to predict outcomes in pts with advanced TGCT. We also analyzed the correlation between ctDNA detection and STM levels. Methods: Blood samples were collected from 31 pts before and after first-line treatment (chemotherapy, primary radiotherapy or retroperitoneal lymphadenectomy). ctDNA detection was performed using a ddPCR assay to identify copy number gains in chromosome 12p, present in 90% of TGCTs. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier curves and the log-rank test. The correlation between ctDNA status and STM alterations was analyzed using Pearson’s correlation test. Results: The median age of participants was 31 years, 81% were non-seminoma, 48% stage III, 45% IGCCCG intermediate-poor risk, 39% Sx-S0 stage, 83% received first-line chemotherapy, and the median follow-up time was 53 months. The ddPCR assay showed 88% sensitivity and 100% specificity for ctDNA detection. ctDNA detection before first-line treatment significantly correlated with altered LDH levels (r=0.78, p<0.001) but did not correlate with altered AFP (r=0.33, p=0.16) or bHCG levels (r=-0.03, p=0.88). Detection of ctDNA before first-line treatment was significantly associated with a shorter 2-year PFS rate (ctDNA positive 64% vs. ctDNA negative 100%, p=0.022) and 2-year OS rate (ctDNA positive 64% vs. ctDNA negative 100%, p=0.014). None of the patients who tested negative for ctDNA detection experienced disease progression or died. Elevated STM levels before first-line therapy were not significantly associated with PFS (p=0.07) or OS (p=0.053). Detection of ctDNA after first-line therapy did not significantly correlate with PFS (p=0.27) and OS (p=0.29), and was not predictive of viable tumor or teratoma in the surgical specimen. Conclusions: This is the first study to use a tumor-naïve ctDNA test to assess outcomes in pts with TGCT. ctDNA detection before first-line therapy may serve as a valuable prognostic biomarker, complementing STM for pts with advanced TGCT. Further prospective studies are needed to validate our findings.
Source: Journal of Clinical Oncology
Authors: Vitor Fiorin de Vasconcellos, Fabiana Bettoni, Mauricio Pereira, Gabriel Watarai, Diogo Araújo, Maria José Alves, Elisangela Monteiro Coser, Ernande dos Santos, Miyuki Uno, Roger Chammas, Diogo Assed Bastos, Anamaria Aranha Camargo
Language: English
Subfield: Surgery
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W4410811045