Modelling of tumour repopulation after chemotherapy

Area of Science:

• Oncology
• Mathematical Biology
• Pharmacokinetics

Background:

• Tumour cell repopulation is a known phenomenon after radiotherapy but is often neglected during chemotherapy.
• The mechanisms driving tumour regrowth after chemotherapy are not well understood.
• Chemotherapy and radiotherapy share similar mechanisms of attacking cancer cells, suggesting repopulation could occur with both.

Purpose of the Study:

• To investigate the impact of tumour cell repopulation during chemotherapy.
• To model the effect of cisplatin on head and neck tumours, including regression and regrowth.
• To explore cell recruitment as a mechanism for repopulation during chemotherapy.

Main Methods:

• Utilized a Monte Carlo modeling approach to simulate cisplatin pharmacokinetics in a virtual head and neck tumour.
• Modeled cell recruitment by releasing quiescent cells into the mitotic cycle post-chemotherapy-induced cell kill (5-50%).
• Simulated both immediate and late onset of cell recruitment to study repopulation dynamics.

Main Results:

• Simulations demonstrated that tumour cell repopulation can occur during cisplatin chemotherapy.
• The study showed that cell recruitment, where quiescent cells enter the cell cycle, is a key mechanism driving this repopulation.
• Repopulation was found to be a potent phenomenon, comparable in impact to drug resistance.

Conclusions:

• Tumour cell repopulation is a critical factor that should be considered during chemotherapy, similar to its role in radiotherapy.
• The phenomenon of cell recruitment significantly contributes to tumour regrowth during chemotherapy.
• Neglecting repopulation during chemotherapy may lead to suboptimal treatment outcomes and requires further investigation.