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Mohs Surgery for Patients with Skin Cancer: A Review of Guidelines

Last updated: March 20, 2019
Project Number: RC1084-000
Product Line: Rapid Response
Research Type: Devices and Systems
Report Type: Summary with Critical Appraisal
Result type: Report


  1. What are the evidence-based guidelines regarding the use of Mohs surgery for the treatment of skin cancer?

Key Message

Nine evidence-based guidelines were identified; two guidelines issued recommendations on basal cell carcinoma, four on squamous cell carcinoma, two on melanoma, and one on Merkel cell carcinoma. Mohs micrographic surgery (MMS) is recommended as a first-line option for high-risk primary or recurrent basal cell carcinoma. For high-risk primary or recurrent squamous cell carcinoma, MMS may be considered as one of the options, especially where tissue preservation or margin controls are challenging, or when the tumour is at a critical anatomical site. For squamous cell carcinoma in situ (Bowden’s disease), MMS may be indicated for digital and penile tumours. MMS may also be considered for melanoma in situ (lentigo maligna) and Merkel cell carcinoma especially when the tumour is in a sensitive area and there are concerns of functional impairment from an excision that is too radical.