The prognostic value of tumor-informed minimal residual disease detection using circulating tumor DNA in first-line treatment of ovarian cancer
This study aims to assess the application and effectiveness of tumor-informed Minimal Residual Disease (MRD) detection using circulating tumor DNA (ctDNA) for predicting disease recurrence and survival outcomes in ovarian cancer patients. Between 2020 and 2022, 31 newly diagnosed stage II-IV ovarian cancer patients were enrolled in this retrospective study. All patients completed standard treatment, including cytoreductive surgery and platinum-based chemotherapy, achieving a complete remission (CR) without receiving first-line PARP inhibitor maintenance therapy. Archived tumor tissue, as well as plasma samples collected pre- and post-treatment, were tested using Whole Exome Sequencing (WES) to identify personalized somatic variants for MRD detection. All pre-treatment (baseline) blood samples showed a 100 % MRD positive rate, demonstrating the high sensitivity of ctDNA-based MRD detection. This rate decreased to 25.8 % in post-treatment (landmark) samples, indicating a significant reduction of ctDNA levels following effective treatment. The median follow-up time until Sep 2023 was 21.4 months, during which 15 patients experienced recurrence. Landmark MRD-positive patients exhibited a markedly shorter median progression-free survival (PFS) compared to MRD-negative patients (5.8 months vs 24.7 months, HR = 6.678, p = 0.01). Furthermore, a strong correlation was observed between post-treatment MRD status and recurrence, with a higher relapse rate in the MRD-positive group. The study establishes MRD detection via ctDNA analysis as a valuable tool for early and accurate prediction of ovarian cancer recurrence, potentially leading to improved clinical outcomes. As a result, integrating MRD detection into routine clinical practice is advocated to enable more effective and personalized treatment strategies for ovarian cancer patients.