Cellular senescence predicts treatment outcome in metastasised colorectal cancer.

<bold>Background: </bold>Cellular senescence is a terminal cell-cycle arrest that occurs in response to activated oncogenes and DNA-damaging chemotherapy. Whether cancer cell senescence at diagnosis might be predictive for treatment outcome is unknown.<bold>Methods: </bold>A senescence index (SI) was developed and used to retrospectively correlate the treatment outcome of 30 UICC stage IV colorectal cancer (CRC) patients with their SI at diagnosis.<bold>Results: </bold>5-Fluorouracil/leucovorin-treated CRC patients achieved a significantly longer progression-free survival when presenting with SI-positive tumours before therapy (median 12.0 vs 6.0 months; P=0.044).<bold>Conclusion: </bold>Cancer cell senescence predicts treatment outcome in metastasised CRC. Prospective analyses of larger patient cohorts are needed. [ABSTRACT FROM AUTHOR]