Prediction of tumour regrowth of pontine glioma using a two-term model

Background: Modelling tumour regrowth kinetics and determining tumour burden is critically important in making accurate patient prognoses. Patients and Methods: Our two-term model, which describes tumour regrowth after chemotherapy was tested by analyzing tumour sizes in patients with pontine gliomas treated at a major cancer centre during the past 40 years. Tumour measurements at four early time points were used to fit the model, which was then used to predict later tumour sizes. The predictions were compared with observed measurements from clinical charts and this model's performance was compared to that of a quadratic model. Results: The mean of relative errors using the two-term model was 0.186; standard deviation, 0.176. For the quadratic model, the mean of relative errors was 0.412; standard deviation, 0.521. Conclusion: The two-term model fits the tumour regrowth data reasonably well and is more accurate than a competing quadratic model used in the same way (p<0.05).