Tumour markers are molecules which may be present in higher than usual concentrations in the tissue, serum or other bodily fluids of patients with cancer. Roughly 15 million are requested in the UK each year. They are used to aid diagnosis, guide treatment choice, monitor progress both during and after treatment and guide prognosis. Inappropriate use for diagnosis can cause anxiety, delay correct diagnosis and have an economical implication to the health service. NICE (National Institute for Health and Care Excellence) indicate only four situations where a tumour marker is used for diagnostic purposes, none of these are the use of multiple requests.
We identified all tumour marker requests within Abertawe Bro Morgannwg University Health Board (ABMU) in Wales between June and December 2015 from both primary and secondary care. We did not include requests from Oncology or Urology. This gave us information about location of request and clinical details for the request. We used patient demographics to see whether there were multiple requests for individual patients. We split the multiple requests from the individual requests and compared these demographics with our local cancer registry. We analysed the clinical notes for those patients who had a positive cancer diagnosis to assess if the tumour marker was of clinical benefit in the diagnostic phase.
In primary care alone there were 12,405 single requests and 985 multiple requests. Of the multiple requests, cancer was only diagnosed in 5% of patients, with the tumour marker being useful in 0.5% of diagnoses. In secondary care there were 4,953 single requests and 762 multiple requests. Of the multiple requests cancer was only diagnosed in 32.4% with the tumour marker being useful in 10% of diagnoses. When extrapolated over a 12-month period there was a cost of nearly £100,000 for the health board.
Inappropriate requesting has economic implications but also increases anxiety and distress for the patient. Unnecessary additional investigations may delay the correct diagnosis and treatment. As a result of the findings we have now provided education through bulletins, presentations and laboratory comments to encourage more appropriate tumour marker requesting consistent with NICE guidelines.
Clinical trial identification
Legal entity responsible for the study
South West Wales Cancer Centre
All authors have declared no conflicts of interest.