Fig. 2

The dynamics of tumour cells and tumour biomarkers in the absence of any immune response (i.e., \(N_{\text {I}}=B_{\text {I}}=0\)), as investigated in [25]: a time-evolution of ovarian cancer cells; a′ tumour size (cell numbers) at the detection times \(D_{T}\), when the CA-125 biomarkers reach the detection thresholds (as shown in b, c); b dynamics of CA-125 biomarker, when we assume only tumour shedding. Horizontal line shows the biomarker detection threshold \(d_{CA125}\). In this case, the tumour detection threshold is \(D_{T}=8.8\) years; see also [25]; c dynamics of CA-125 biomarker, when we assume both tumour and healthy cells shedding. Horizontal line shows the biomarker cut-off threshold \(c_{CA125}\). In this case, the tumour detection threshold is \(D_{T}=10.1\) years; see also [25]. The parameter values for these simulations are given in Table 1