Nationwide real-world usage of blood-based (liquid) biomarker testing in Japan.

Abstract

e23311 Background: Despite the advances in precision oncology with biomarker testing including CGP (comprehensive genomic profiling), not all patients are able to benefit from tissue-guided treatment decisions, underscoring a significant demand for advancements in liquid-based biomarker testing for such patients. However, the treatment landscape based on the application and integration of liquid biopsy in clinical practice has yet to be fully characterized in Japan. Methods: Center for Cancer Genomics and Advanced Therapeutics (C-CAT), the national datacenter in Japan, was established by the Ministry of Health, Labour and Welfare (MHLW) with the start of cancer genome medicine since June 2019. The database collects the clinical and genomic data from 68,242 patients who underwent CGP by the end of 2023. This study included all patient records who underwent liquid CGP testing using FoundationOne Liquid test from the C-CAT database up to June 2023. Results: We analyzed data from 7,461 records, where the patients had an average age of 65.1 (±12.0) years; 58.8% were male. A majority (51.3%) exhibited an ECOG performance status of 0, and 66.5% reported a family history of carcinoma. Predominant cancer types included pancreatic (1,825; 24.5%), prostate (1,182; 15.8%) and biliary tract cancers (838; 11.2%). Following review by an MTB (molecular tumor board), new treatments were initiated in 5.8% (434) of cases, with targeted therapy (181; 41.7%) and chemotherapy (174; 40.9%) being the primary interventions. Separately, 9 (2.1%) of new treatments post-MTB occurred as part of clinical trials. Median (IQR) durations from specimen collection to MTB, MTB to treatment initiation, and specimen collection to post-MTB treatment were 28 (24-34), 35 (13-64), and 63 (42-94) days, respectively. The largest proportion of biomarker testing occurred after the start of second line of therapy (1,720; 23.1%) Pancreatic and biliary tract cancer patients tend to have biomarker testing at the earlier line, whereas prostate and ovarian cancer patients tend to have at the later line. Conclusions: Although the positioning of liquid CGP testing may differ among cancer types, it is important for patients to select appropriate tissue- and liquid-based biomarker testing at the right timing. Understanding this descriptive landscape of biomarker tests utilized in real-world settings will aid decision-making for addressing unmet needs (e.g., low accessibility to treatment) in cancer genome medicine and its positioning in improving the standard of cancer care.