Tumor dormancy at bedside: A late awakening.

Breast cancer recurrence may occur at variable times following primary tumor removal. The corresponding event dynamics displays a structured multipeak pattern, which can be explained by the occurrence of microscopic phases of metastasis quiescence (tumor dormancy) followed by wake up, growth and timed clinical appearance. This model provides a meaningful justification of the early recurrence pattern and even explains the effectiveness of adjuvant systemic therapies. Yet, late recurrences, which were less investigated, are fairly little known and a few researchers supported their steady state appearance. We report here the analysis of the late clinical course from patients who were disease-free at 5 years of follow-up, which again displays a structured pattern, supporting the view that tumor dormancy can explain the late recurrence risk as well. Tailored treatments are needed to address late clinical recurrences.