It’s a step forward that NICE are recommending better access to diagnostic tests for GPs and have moved to a more symptom-based, rather than cancer-based approach. But while they acknowledge that multiple symptoms map to multiple cancers, it’s a shame they haven’t been able to understand and use results of the key multivariate analyses available, such as those used within QCancer, which is more efficient at identifying the patients most likely to have cancer.
Also, it is disappointing that NICE has not addressed the concerns raised by many stakeholders about the draft version. These include multiple concerns around age cut-offs – for example, that the guidelines will miss significant numbers of lung cancers in people under the age of 40 and breast cancers in women under 50.
Concerns over the removal of established risk factors, such as family history of breast cancer and intermenstrual and post-coital bleeding for cervical cancer, have also been dismissed. The guidelines panel has not presented a cogent argument for adopting a 3% threshold using positive predictive values based on simple combinations of symptoms, rather than a more sophisticated risk assessment approach that combines multiple symptoms with key risk factors such as age, smoking and family history to calculate a validated measure of absolute risk. This means we have no idea of the sensitivity of the approach (for example, how many patients at risk will be correctly picked up and how many will be missed).
In other words, we may be missing high-risk patients while putting too many low-risk patients through tests.
The panel also does not appear to have addressed the large number of concerns raised by stakeholders including NHS England, Cancer Research UK and Macmillan about whether such long and complicated guidance could ever be implemented by GPs in everyday clinical practice.
In my view, they have missed a long awaited opportunity to improve early diagnosis of cancer.
Professor Julia Hippisley-Cox is professor of epidemiology and general practice at the University of Nottingham, lead researcher for the QCancer risk assessment tool and director of ClinRisk Ltd.