Health economic assessment of Ovatools

Ovarian cancer is the 6th most common cause of death from cancer in UK women. Most ovarian cancers are detected when the disease is advanced which makes them harder to treat; women from poorer households and ethnic minority backgrounds are more likely to be diagnosed with late ovarian cancer. Earlier diagnosis has the potential to improve treatment outcomes including survival. Currently the guideline producing body NICE, recommend testing the blood for cancer antigen 125 (CA125) in women who visit general practice (GP) with symptoms of possible ovarian cancer. If the test levels are high (≥35 U/mL), an ultrasound scan is then recommended. However, the risk of having ovarian cancer varies greatly between patients with different CA125 levels and of different ages. In a recent study, we developed Ovatools - models which take account of both age and CA125 level to estimate the risk (in percentage) of ovarian and other cancers in women having a CA125 test in primary care. On initial evaluation, these models performed well identifying 86% of women with ovarian cancer (applying a 1% Ovatools risk threshold). They have the potential to help pick up ovarian cancer in primary care and to help ensure women are referred and can start appropriate treatment in a timely way. The models are currently being validated in a separate study to ensure their reliability.

To get a clear idea of the clinical and economic implications of using Ovatools in primary care, we plan to carry out a new study. We will develop a health economic model which will look at the ovarian cancer diagnosis and treatment pathway. This health economic model will refer to the framework of previous health economic assessments used by NICE, but will update the pathway and include much greater detail on patients such as age, CA125 level and estimated cancer risk. In addition, through use of hospital and mortality data, we will know what subsequent tests patients had following CA125 testing or/and ultrasound scan, and whether/when they were diagnosed, at what stage, what treatments were used and survival. Published data will add information on the performance of ultrasound and CT tests in picking up cancer; the risk of cancer growing/spreading further (‘progression’); and quality of life associated with the diagnostic pathway and cancer stage. We will use this enhanced model to assess the outcomes (cases detected and quality of life-adjusted survival) and cost-effectiveness of using different Ovatools risk thresholds and additional tests (either alongside or following CA125) in the ovarian cancer diagnostic pathway. This health economic analysis is essential to understand whether Ovatools could improve the current ovarian cancer diagnostic pathway and, if so, to ensure that they are used in the best way possible.

Amount Awarded: £50,000