Background: Melanoma diagnosis remains a constant challenge in clinical practice and although dermoscopy greatly improves clinical diagnosis, the benign to malignant excision ratios remain high. This led to the advent of confocal microscopy a non-invasive technique which aims to improve diagnostic accuracy. As with any diagnostic technique it produces both false negative and false positive diagnoses, with false negatives leading to melanomas not being excised at all or belatedly after confocal examination.
Methods: A literature review was performed searching the databases Medline, PubMed, Scopus, Informit Health and Cochrane Library. Keywords included “confocal microscopy”, “melanoma”, “pigmented lesion”, “false negative and “diagnostic accuracy”. With database and reference list perusal, 45 articles were identified and reviewed.
Results: The key findings of the studies show that to reduce melanoma mortality sensitivity of the testing modality and early diagnosis are key. Many papers found false negatives occurred and this can lead to misdiagnosis of a melanoma where the lesion is not excised and risks progression, metastasis and increased mortality. These numbers have been small however, and support confocal microscopy can be used support the decision to excise, enrol in monitoring or confirm a benign diagnosis.
Conclusion: Upon identifying a concerning lesion, a thorough history with clinical examination aided by dermoscopy with excision of concerning lesions is and likely should remain the gold standard for melanoma management. Before confocal microscopy can be used outside of well conducted trials it must demonstrate at least equivalent sensitivity to usual medical care and ideally document an overall benefit in terms of morbidity, mortality and cost.