Antiangiogenic inhibitors offer a promising new treatment modality in oncology. However,
the optimal administration regime is often not well-established, despite the fact
that it might have substantial impact on the outcome. The aim of the present study
was to investigate this issue. Eight weeks old male C57Bl/6 mice were implanted with
C38 colon adenocarcinoma, and were given either daily (n = 9) or single (n = 5) dose
of bevacizumab; both receiving the same dose the only difference being the administration
pattern. Outcome was measured by tracking tumor volume; both caliper and magnetic
resonance imaging was employed. Longitudinal growth curves were modelled with mixed-effects
models (with correction for autocorrelation and heteroscedasticity, where necessary)
to infer on population-level. Several different growth models (exponential, logistic,
Gompertz) were applied and compared. Results show that the estimation of the exponential
model is very reliable, but it prevents extrapolation in time. Nevertheless, it clearly
stablished the advantage of the continuous regime.