Circulating tumour cells (CTCs) in haematological malignancies: Advances in biology and clinical relevance with a focus on multiple myeloma.

Circulating tumour cells (CTCs) are malignant cells that detach from primary tumours and disseminate systemically through the bloodstream. While the U.S. Food and Drug Administration (FDA) has approved CTC detection for certain solid tumours, its application and investigation within haematological malignancies remain a significant area of ongoing research and development. As a non-invasive method, CTC analysis enables dynamic monitoring and demonstrates considerable potential for early prediction, enhanced diagnostic accuracy, real-time treatment monitoring and robust prognostic assessment, offering broad clinical relevance. This review outlined the biological characteristics of CTCs in the context of haematological diseases, with a particular focus on their role in clinical diagnosis, treatment response and prognostic evaluation. It explored the correlation between CTC detection and established haematological and molecular biomarkers, while also addressing current limitations and providing an outlook on future advancements. Although full integration of CTC detection into routine clinical practice necessitates standardized procedures and a more profound understanding of its molecular complexities, it promised to significantly enhance diagnostic and prognostic accuracy. With continued technological progress, CTC detection is poised to become a pivotal tool in advancing personalized precision medicine for the management of haematological malignancies.