The cost-effectiveness of skin surveillance through a specialised clinic for patients at high risk of melanoma, compared with standard care.

Abstract

Clinical guidelines recommend that people at high risk of melanoma receive regular surveillance, as prognosis is better if melanomas are detected at an early stage. In this thesis, I conducted a systematic review of international clinical practice guidelines for identification, screening and follow-up of individuals at high risk of primary cutaneous melanoma, and analysed population-based data on their characteristics and actual management practices using data from the New South Wales Melanoma Patterns of Care study. I found a high degree of variation in international guidelines regarding identification and follow-up recommendations, mainly due to low levels of evidence. From the MPOC study, I found that age at diagnosis and body site of the melanomas differed according to patients’ specific risk factors. The main body of work in this thesis concerned the evaluation of the costs and benefits of a specialised ‘High Risk Clinic’ for surveillance of people at very high risk of melanoma, using data from the Clinic and a population-based dataset comprising linked data from various sources. My research built on a previous study that found melanomas were detected at an early stage and excision rates were reduced using the High Risk Clinic protocol. First, I undertook a micro-costing study to understand service delivery and costs of a High Risk Clinic. The mean annual health system cost of $1,009 per patient was comparable with the societal costs of $972 reflecting the time patients spent attending the clinic. Then, to examine the cost-effectiveness of the High Risk Clinic, I built a decision-analytic model to compare the costs and benefits of the Clinic compared to standard care in the community. I found that surveillance through the High Risk Clinic was both less expensive and more effective than standard care. Over ten years, the mean saving was AUD $8,451 (95% CI $7,174-$9,719) per patient, and the mean quality-adjusted life year (QALY) gain was 0.31 (95% CI 0.27-0.35). The main drivers of the differences were detection of melanoma at an earlier stage resulting in less extensive treatment, and a lower annual mean excision rate for suspicious lesions in the High Risk Clinic compared to standard care. The findings in this thesis have important policy and practice implications for the management of people at high risk of melanoma.