The cost-effectiveness of medical versus surgical androgen deprivation therapy for advanced prostate cancer in Tanzania: a Markov model-based analysis.

Background: Androgen deprivation therapy (ADT) is a recommended treatment for patients with advanced prostate cancer, mostly for palliative purposes. In limited resource settings, decision-making about palliative treatment should be guided by the overall survival benefit of one option over another, patient life expectancy, quality of life, and cost. Purpose: This study aimed to evaluate the cost-effectiveness of medical androgen deprivation therapy compared to surgical androgen deprivation therapy among patients with advanced prostate cancer in Tanzania. Methods: A model-based economic evaluation study design, was conducted using retrospective patient records from tertiary hospitals in Tanzania and published literature. A Markov model with a five-year time horizon was developed to simulate disease progression among patients receiving either medical ADT or surgical ADT. Health states included local recurrence, asymptomatic metastatic disease, symptomatic metastatic disease, death from prostate cancer, and death from other causes. Costs were estimated from provider and societal perspectives and expressed in US$. Health outcomes were measured in quality-adjusted life years (QALYs). Incremental cost-effectiveness ratios (ICERs) were calculated and compared against a willingness-to-pay threshold based on Tanzania's gross domestic product (GDP) per capita (US$1,099) as the cost-effectiveness threshold. Alternative willingness-to-pay thresholds, including three times GDP per capita (US$3,580), were explored in sensitivity analyses. Probabilistic sensitivity analysis using Monte Carlo simulation was performed to assess uncertainty. Results: Medical ADT generated higher costs and greater health benefits than surgical ADT. The total cost of medical ADT was estimated at US$50,639.98 compared with US$6,917.51 for surgical ADT. Medical ADT produced a cumulative cohort-level effectiveness equivalent to 105.63 QALYs compared with 4.06 QALYs for surgical ADT, resulting in an incremental gain of 101.58 QALYs. The ICER for medical ADT was US$430.44 per QALY gained, which remained substantially below the selected willingness-to-pay threshold of US$1,099 and alternative threshold of US$3,580 per QALY. Probabilistic sensitivity analyses demonstrated that medical ADT remained cost-effective across a wide range of parameter assumptions. Conclusion: Medical ADT was more costly but also more effective than surgical ADT for managing advanced prostate cancer in Tanzania. The estimated ICER remained below the willingness-to-pay threshold, indicating that medical ADT represents a cost-effective treatment strategy. Further studies incorporating local utility estimates and long-term survival outcomes are warranted to strengthen economic evidence for prostate cancer management in Tanzania.