Detection of metastases. The percentage of clinically detectable metastases relative to the total number of metastases within a patient is plotted here versus the time interval from the removal of the primary tumor to detection. This plot was based upon the 4000 simulations cells. A latent period provided in Fig. 2, and the detection threshold was set at 109 was apparent, where the metastases remain clinically occult, followed by a period where the proportion of overt metastases rapidly increased.