Methods for diagnosing amelanotic/hypomelanotic melanoma (AHM)

Amelanotic/hypomelanotic melanoma (AHM) is the most lethal skin cancer in the world. The diagnosis of AHM is of great challenge due to its nonspecific clinical manifestation (how it looks). Dermoscopy and reflectance confocal microscopy (RCM) are non‐invasive (meaning they don't harm the skin) techniques for the diagnosis of skin lesions. Several studies have proven the importance of dermoscopy and RCM in the diagnosis of pigmented melanoma and non‐melanoma skin cancers, but their accuracy for AHM has not been systematically studied. In this study, the authors aimed to investigate the accuracy of dermoscopy and RCM respectively and compare the accuracy between them for diagnosing AHM. They searched several databases for eligible studies about dermoscopy, RCM and AHM from inception to June 31, 2019. Seven studies with a total of 1111 lesions were included in the study. In medical diagnosis, test ‘sensitivity’ is the ability of a test to correctly identify those with the disease, whereas test ‘specificity’ is the ability of the test to correctly identify those without the disease. The results showed that the pooled sensitivity and specificity of dermoscopy for the diagnosis of AHM were 61% and 90%, respectively. The corresponding values of RCM for the diagnosis of AHM were 67% and 89%, respectively. In conclusion, the study demonstrates that both dermoscopy and RCM offer good diagnostic accuracy with high specificity and moderate sensitivity in the diagnosis of AHM. RCM is more accurate than dermoscopy in diagnosing AHM but the comparison needs to be confirmed. Linked Article:   Lan et al . Br J Dermatol 2020; 183 :210–219.