Kaplan–Meier estimate of survival function.

<p>Kaplan–Meier estimate of survival function of metastatic breast cancer patients separated on CTC-positive (red line) and CTC-negative (blue line) groups. The survival period in month of the corresponding patient. Censored patients are indicated by vertical bars (|). Statistical significance determined by log-rank test. Shorter survival correlates with presence of CTCs in blood (<i>P:</i> 0.0332, HR: 7.38, (CI = 0.84-64.09)).