Identifying melanomas in primary care: can we do better?BMJ 2012; 345 doi: https://doi.org/10.1136/bmj.e4244 (Published 04 July 2012) Cite this as: BMJ 2012;345:e4244
- 1Leeds Institute of Molecular Medicine, Leeds LS9 7TF, UK
- 2University of Manchester/Christie NHS Hospital, Manchester M20 4BX, UK
The prognosis for patients with melanoma depends on the stage of disease at diagnosis. In some European countries tumour thickness is much higher at presentation than in others, with consequent adverse effects on survival.1 The thickness of tumours at presentation to secondary care in the United Kingdom is such that the overall survival at five years is around 80% for men and 90% for women.2 Survival rates are higher in some countries, such as Australia, where excision of thinner tumours is more common.3 Such better outcomes are thought to be due to higher levels of awareness among patients and general practitioners.
The incidence of melanoma continues to increase in many areas of the world, and greater awareness is needed so that the thickness of tumours at presentation is reduced without excessive increases in referral to secondary care. In the linked study (doi:10.1136/bmj.e4110),4 Walter and colleagues tested a computerised diagnostic tool, the MoleMate system, as a means of increasing diagnostic accuracy and referral to secondary care for suspicious pigmented lesions.
Cancer referral guidelines have been developed in the UK to promote more appropriate referrals, and a recent audit in Scotland showed that the rate of appropriate referral for melanoma was low.5 A total of 18 775 urgent, suspected cancer referrals were analysed from 516 general practices. Compliance with referral guidelines was 90.9%. The referral rate ranged from 3.7 to 24.0 per 1000 per annum; 30.8% of referrals were for patients aged under 50 years, yet this age group accounts for only 11.1% of all diagnosed cancers; 10.3% of referrals were for suspected melanoma, yet this cancer accounts for only 4.1% of new cancers. The proportion of patients correctly referred with suspected melanoma was 11.8%, compared with 61.7% for suspected leukaemia. The relatively high rate of referral for suspected melanoma and the relatively low positive pick-up rate reflect a lack of diagnostic confidence in primary care. This audit confirmed the findings of another study designed to investigate the appropriateness of referrals under the two week referral system for suspected cancers in the UK.6 This study found that the proportion of melanomas and squamous cell carcinomas correctly referred was around 20%, and this rate did not improve after the introduction of targeted education.
The MoleMate system reported here is based on computerised analysis of light reflected by the skin. Several tools for detecting melanoma have been reported over the years, many of which have been based on dermoscopy. Although they are often viewed positively by patients, their high false positive rate has limited their use.7
The authors of the current study specifically tested the MoleMate tool as an aid to diagnosis in primary healthcare teams. Fifteen general practices in the east of England took part, and the appropriateness of referral was based on the proportion of patients referred who were either subsequently reviewed or had biopsies. All patients with a suspicious pigmented lesion were internally referred to a primary care physician who had been specially trained to follow best practice diagnostic guidelines, including the use of the seven point check list originally devised by Mackie8; for those randomised to the intervention they also applied the MoleMate system. Patients judged to have a benign lesion were offered a follow-up appointment three to six months later. Use of the MoleMate system did not result in more appropriate referrals than in the controls. Indeed use of this tool was associated with poorer recognition of benign lesions and a higher referral rate. It was interesting that patients and clinicians viewed the use of the technology positively, with increased diagnostic certainty in clinicians and reduced anxiety in patients.
The increased rate of referral in the MoleMate group is reminiscent of the observation that dermatologists show increased concern about borderline lesions when they first start to use dermoscopy to examine naevi. This increased referral rate might therefore have settled over time. Nonetheless, the technology was not of benefit. Although this is a negative study it is an important formal attempt to assess a new technology. Doctors and patients are often seduced by new technologies—in this study, both doctors and patients liked MoleMate, but the value of new technologies must be proved.
The authors compared the use of MoleMate technology to “best practice.” Clearly best practice was an enhanced standard of care, and it is therefore not possible to compare referral rates with those in previous reports from the UK. However the outcomes for the control arm were encouraging and suggest that simple measures such as enhanced targeted education and internal referral could reduce inappropriate referrals. Diagnostic difficulty within primary care remains a problem and increased education of the public and primary healthcare teams is essential. In the UK, general practitioners have little training in dermatology, either as undergraduates or postgraduates, and this is probably reflected by the higher average stage of melanoma at presentation in the UK compared with many other European countries.
Cite this as: BMJ 2012;344:e4244
Competing interests: Both authors have completed the ICMJE uniform disclosure form at www.icmje.org/coi_disclosure.pdf (available on request from the corresponding author) and declare: no support from any organisation for the submitted work; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work.
Provenance and peer review: Commissioned; not externally peer reviewed.