GPs and cancer patients could be given a more reliable way to tackle cancer patients’ questions about their prognosis and how long they are likely to survive, after researchers developed a new system for predicting cancer survival.
Researchers developed a scoring system that is more reliable than doctors’ attempts to predict whether a terminally ill cancer patient would survive for days, weeks or months.
Using a combination of clinical and laboratory variables known to predict survival, the team created two prognostic scores to predict how long 1,018 patients with advanced cancer in different care settings were likely to survive.
Factors that could have affected the results, such as age, gender, ethnicity, diagnosis, and extent of disease, were taken into account.
Both scores – called PiPS-A and PiPS-B – were at least as accurate as a clinician’s estimate, and PiPS-B, which required a blood test to analyse for haematological and biochemical parameters, was significantly better than an individual doctor’s or nurse’s prediction.
Using the PiPS-A models performed at least as well as the clinicians and were correct on 59.6% of occasions, while multi-professional predictions were correct on 57.5%.
The PiPS-B models performed significantly better than either doctors, and was correct 61.5% of the tim compared with 52.6% for doctors, and was also a better predictor than nurses, correctly predicted survival on 61.5% of occassions compared with 52.3% of nurses’ predictions.
But the scores were not significantly better than a multi-professional estimate.
This is the first study to benchmark a prognostic scoring system against current best practice, say the authors in the BMJ.
The reserachers said the score could help GPs and carers better plan palliative care services, but they stressed further validation work would be needed before the scales can be recommended for use in routine clinical practice.
Study leader Dr Paddy Stone, reader in palliative medicine at St George’s, University of London, concluded: ‘These models are able to identify reliably those patients with expected prognoses of ‘days’, ‘weeks’, or ‘months/years’ and can be used in either competent or incompetent patients and in circumstances when blood results are available and when additional investigations would be inappropriate.’
BMJ 2011, online 25 August.