Mohs and the benefits of new embedding and staining systems

Mohs practice in the UK has been expanding steadily over the past decade. The incidence of skin cancer, in particular non-melanoma skin cancer (NMSC), has been steadily increasing. The most significant tumour type contributing to this increase is basal cell carcinoma (BCC). According to statistics from the British Skin Foundation website, BCC accounts for >80% of all the skin cancers recorded in the UK. It remains the most common skin cancer with large numbers of the Caucasian population likely to develop a BCC at some point in their lives. These tumours can occur anywhere on the body, but are more commonly seen in sun-exposed sites such as the face, head, neck and ears. It is also the case that BCCs can occur at the sites of former burned tissue, scars or ulcers that have damaged the integrity of the skin.

As a junior biomedical scientist, I recall seeing histology request forms of patients with BCCs and for the large part they were all patients in their 60s or over. Perceptually, I classified this particular common tumour as a cancer of older age. However, as time has gone by we have seen the incidence of NMSC rise, primarily due to increased levels of exposure to the main causative agent, sunlight and more specifically the ultraviolet (UV) spectrum of light involving the wavelengths of UVA and UVB.

I manage a large Mohs laboratory, one of the largest of its type in the UK, and I see BCCs on patients in their early 30s and 40s. Admittedly the large majority of these younger patients are strict ‘sun worshippers’ and also partial to the use of sun beds to top up their tans. The imperative observation is clear, in that the number of BCCs that pathology laboratories will be dealing with will continue to increase for the foreseeable future. This is in spite of a much clearer understanding of how we all should be protecting ourselves from the long-term effects of sun damage to our skin.