Personalised Disease Monitoring in Metastatic Breast Cancer

Patients with metastatic breast cancer may respond well to treatment and metastases can remain stable for several years. Despite personalised medicine being increasingly used for diagnosis and treatment, follow-up still include radiological response evaluation every 3-4 months, which renders a significant number of 'unnecessary' exams for patients with long-term stable disease. Increasing evidence indicates that tumour markers such as circulating tumour DNA (ctDNA), thymidine kinase 1 (TK1) and cancer antigen 15-3 (CA15-3) may be useful for disease monitoring in the metastatic setting. However, algorithms that accurately define the time-points at which imaging can be foregone or reinstituted when progression is forecast, have not been developed. This study will measure ctDNA, TK1 and CA15-3 at all imaging time-points. The primary aim is to develop an algorithm based on these biomarkers, alone or in combination, that with sufficient specificity and sensitivity can advise whether a scan can be safely omitted at a specific time-point, for patients with MBC receiving first line therapy with AI plus cyclin dependent kinase 4/6 inhibitor (CDK4/6i). Additional samples will be stored such that novel biomarkers can also be tested in future. The cost-effectiveness of using the devised biomarker protocol will be evaluated.

NCT Number	NCT04597580
Lead Sponsor	The Christie NHS Foundation Trust Collaborators: Sahlgrenska University Hospital
Conditions	Breast Cancer Metastatic, Estrogen Receptor-positive Breast Cancer
Enrollment	97 participants
Start Date	2019-05-08
Primary Completion	2026-05-31 (estimated)
Study Completion	2030-01-31 (estimated)
Updated on ClinicalTrials.gov	2025-12-02