The Cochrane Database (CDSR) is a leading facility for systematic reviews in health care. Reports are produced by a global, independent network of researchers, professionals, patients, carers and other health specialists.
In December 2018, they collated information on techniques for diagnosing skin cancer, from a special collection of their reviews. The majority are publicly available and can be viewed on the Cochrane website.
A senior advisory group, including skin cancer specialists, oncologists and plastic surgeons provided useful conclusions on skin cancer diagnosis:
- Inspection using the naked eye alone is not sufficient and melanomas may be missed.
- Smartphone applications intended to monitor new and changing moles, or lesions have a high chance of missing melanomas.
- In specialist hands, dermoscopy (a well lit, hand held microscope) is more effective than visual inspection for diagnosing melanoma and may help with identifying basal cell carcinoma.
- Dermoscopy can help GPs to identify suspicious lesions, checklists to assist with interpretation may be useful. Levels of expertise are however variable in primary care, any uncertainty should be referred to a specialist.
- Where referral isn’t practical, teledermatology i.e. remote, specialist assessment of lesions using dermoscopic images and photographs can support GPs.
- Computer aided diagnosis using artificial intelligence techniques is able to spot more melanomas than doctors using dermoscopy. The downside is more false positives, which can lead to unnecessary surgery.
- Whilst further research is needed on modern methods such as reflectance confocal microscopy (RCM) the evidence suggests that RCM may be better than dermoscopy for the diagnosis of melanoma in lesions that are difficult to diagnose.
- Similarly, further studies are needed on the use of high frequency ultrasound, or electrical impedance spectroscopy. The latter does show promise, particularly for malignant melanoma.
The overriding statement accompanying the points is a vital one. “Early and accurate detection of all skin cancer types is essential to manage the disease and to improve survival rates in melanoma.”
The Research & Skin Care Network
As the advisory group stated, future studies on diagnostic skin cancer tests should recruit patients with suspicious skin lesions at the point where the test under evaluation will be used.
This logical approach reflects our daily work, especially as a way to further evaluate the latest technology. Our London clinic offers reflectance confocal microscopy and electrical impedance spectroscopy, which we and our patients benefit from.
Apart from greater accuracy in some situations, they are non invasive imaging techniques. RCM in particular allows our consultants to carry out a virtual biopsy, with no surgery, or associated risks.
Patients attending for skin cancer diagnosis feel this is a significant benefit, one we hope can become more widely available.