Dormant Tumor Cells: Current Opportunities and Challenges in Clinical Practice

Tumor dormancy plays a pivotal role in cancer relapse. Dormant tumor cells have been identified in distant sites, even in early-stage tumors, and are associated with worse outcomes. This review explores the current understanding of the molecular and cellular mechanisms behind tumor dormancy, including the role of the immune system and the microenvironment. Targeting dormant tumor cells could be a therapeutic strategy to offer long-term remission and potentially cure cancer. Unfortunately, the translation of this knowledge in clinical practice is lacking. We assess the feasibility of detecting and measuring dormant tumor cells in clinical practice, and give an overview of potential therapeutic targets, both in terms of maintaining tumor cells in a dormant state, and in terms of eradicating this tumor population.