Transarterial chemoembolisation is a therapeutic approach for vascularised tumours, such as prostate tumours, involving the administration of drug-eluting microspheres. Its efficacy arises from the combined effects of anti-tumour drugs and blood flow occlusion. Microspheres are now commonly generated using lab-on-a-chip systems. This study presents a computational simulation model to evaluate the input flow conditions required to produce PLGA microspheres of specific sizes.