Dermoscopy as an adjunct to surgical excision of non-melanoma skin lesions: a systematic review and meta-analysis

Context: Non-melanoma skin cancers (NMSC) have an incidence of 152,000 cases per year in the UK which continues to rise. Incomplete excision rates for NMSC are estimated to be around 10% and result in patients having a higher risk of recurrence or having to undertake further treatment. Objective: To determine whether the use of dermoscopy as an adjunct to clinical examination could improve the rates of incomplete excision in non-melanoma skin lesions.Method of literature search: Electronic literature search of MEDLINE, EMBASE and Central databases plus manual reference checks of articles on dermoscopy use in surgery between inception and November 2020. Two levels of screening were used on 452 studies. A random effects model was used in the meta-analysis with the DerSimonian-Laird method used to pool data.Results: A total of six fully extracted studies were included for a total of 592 patients were included, with five of these studies reporting on basal cell carcinomas and one reporting on squamous cell carcinomas. The odds ratio of incomplete excision when guided by dermoscopy was 0.29 (95%CI 0.25; 0.34). Heterogeneity was assessed with the I2 statistic and was found to be 0%. Limitations: The number of studies included is small, with three of the studies from the same authors. Studies included are non-randomised and as such hold a significant risk of bias. Conclusion: Incomplete excision rates were reduced when using dermoscopy to mark surgical excision margins in comparison to naked eye evaluation alone