Markov Models in Health Technology Assessment: Cost-Effectiveness Analyses Using Literature- and Trial-Based Data in Breast and Ovarian Cancer

Background: Cancer is one of the leading causes of death worldwide and a major driver of health system costs. Advances in prevention and treatment have improved survival rates, but the rising prevalence and escalating costs of new therapies intensify pressure on healthcare systems. Economic evaluation within Health Technology Assessment provides an evidence-based framework to guide the allocation of resources. Markov modelling is widely used to capture long-term costs and outcomes in oncology; however, its robustness relies on the type of data used. Methods: This thesis employed Markov modelling in two case studies in oncology to assess the cost-effectiveness of preventive and therapeutic strategies, and to investigate how data sources impact outcomes and transferability. Case Study A assessed risk-reducing surgery versus surveillance and no intervention in women with pathogenic BRCA variants in Italy, using literature and registry data. Case Study B evaluated a single dose versus a standard six-monthly zoledronic acid regimen in early breast cancer in Canada, based on pragmatic randomized controlled trial data. Results: Case Study A found that surgery was cost-effective compared to alternative strategies, although the results were sensitive to assumptions regarding uptake and treatment costs. Case Study B suggested that a single dose of zoledronic acid may be a cost-effective alternative; however, the short follow-up period limited the ability to draw longer-term conclusions. Across both cases, the type and quality of data sources strongly influenced model design, robustness, and transferability. Conclusion: This thesis shows how economic modelling can inform cancer prevention and treatment policy, while highlighting that outcomes are shaped by the evidence base. Using distinct data sources, the case studies illustrate the strengths and limitations of Markov models in guiding cost-effective, patient-centred care.