LAUSR

We thank Ma et al. for suggesting the inclusion of in-situ squamous cell carcinoma (SCC-IS) to the commonly used ratio, basal cell carcinoma (BCC):SCC. Indeed, we concur with the authors that superficial BCC is usually managed similarly to SCC-IS. However, equating superficial BCC with a precursor lesion (SCC-IS) on the basis of similar management approaches, would be a confusing strategy. The strength of the BCC:SCC ratio lies in its ability to facilitate easy comparison of incidence rates between what is generally considered a relatively innocuous keratinocyte tumour (BCC),1 with that of one that carries significant metastatic potential (invasive SCC).2.