Sensitive circulating tumor DNA–based residual disease detection in epithelial ovarian cancer

• DOI: 10.26508/lsa.202402658
• Publication Date: 2024-04-05T14:10:22Z
• Authors: Heini ML Kallio; Kalle Savolainen; Tuomo Virtanen; Lauri Ryyppö; Hanna Selin; Päivi Martikainen; Synnöve Staff; Kati Kivinummi; Joonatan Sipola; Juuso Vuorinen; Jussi Nikkola; Matti Nykter; Annika Auranen; Matti Annala
• Keywords: 0301 basic medicine; 3123; 03 medical and health sciences; 3126; 610; 3111; Research Articles

Epithelial ovarian cancer (EOC) is one of the leading causes of cancer-related death in women worldwide, and is characterized by a high rate of recurrence after surgery and chemotherapy. We sought to implement a circulating tumor DNA (ctDNA)–based blood test for more accurate post-operative surveillance of this disease. We analyzed 264 plasma samples collected between June 2016 and September 2021 from 63 EOC patients using tumor-guided plasma cell-free DNA analysis to detect residual disease after treatment. Assay specificity was verified using cross-patient analysis of 1,195 control samples. ctDNA was detected in 51 of 55 (93%) samples at diagnosis, and 18 of 18 (100%) samples at progression. Positive ctDNA in the last on-treatment sample was associated with rapid progression (median 1.02 versus 3.38 yr, HR = 5.63,P< 0.001) and reduced overall survival (median 2.31 versus NR yr, HR = 8.22,P< 0.001) in patients with high-grade serous cancer. In the case of 12 patients, ctDNA assays detected progression earlier than standard surveillance, with a median lead time of 5.9 mo. To approach the physical limits of ctDNA detection, five patients were analyzed using ultra-sensitive assays interrogating 479–1,856 tumor mutations, capable of tracking ctDNA fractions down to 0.0004%. Our results demonstrate that ctDNA assays achieve high sensitivity and specificity in detecting post-operative residual disease in EOC.