Make the most of Mohs

Make the most of MOHS

Whether you’re on a beach or seated in the winter sun in your favourite easy chair, most of us revel in the South African sunshine. However, without adequate skin protection, we are at high risk for various types of skin cancer (although there are also people who don’t spend time in the sun who get skin cancer). If you get skin cancer, it’s essential to remove it – otherwise it could change and grow (metastasize) and end up in the lymph system or other organs of the body, which is potentially fatal. While skin cancers that develop slowly can be treated using light therapy, lotions or medication, more aggressive types of skin cancer have to be removed surgically. This includes malignant melanoma, which is extremely aggressive, and other nonmelanoma types of skin cancer – basal cell carcinoma and squamous cell carcinoma. ‘The “Gold Standard” surgical method used worldwide for the most effective removal of skin cancers is Mohs surgery, which went through a process of development overseas,’ says Dr Pieter du Plessis, who is based at the Life Brooklyn Day Hospital in Pretoria. Mohs surgery is an economical, precise and sophisticated technique that eradicates skin cancers.

‘What is critical about skin cancer is that you must get rid of it completely, so that it can’t recur, and Mohs surgery does just that. After Mohs surgery you can assure the patient that the cancer has been entirely removed,’ he says.

What is critical about skin cancer is that you must get rid of it completely, so that it can’t recur

‘If one imagines that you are cutting out half a grapefruit from the healthy tissue, then it is easier to understand. The fleshy part of
the half is the “cancer”, while the peel is the “healthy tissue”,’ explains Du Plessis. ‘Then, while the patient waits in a day ward, the
dermatologist removes the cancer from the “grapefruit” and then makes incisions in the “peel” so that he can lay it flat.’

With the so-called healthy tissue lying flat he can process them into histology sections and examine them in a specialised histology laboratory, including a cryostat machine (set up at Life Brooklyn Day Hospital specifically for this purpose) and specific microscopy. ‘A competent histo-technologist is necessary for this type of surgery, as he or she has to prepare the slides by cutting thin wafers of tissue and staining them so they can be carefully examined by the dermatologist.’

If the surgeon then sees any buds of cancerous tissue that may have been left behind he goes back to the site of the wound and removes only the affected tissue, once again only taking out a thin layer of healthy tissue. When the surgeon is sure that no cancer remains at the site of the wound, a Mohs or reconstructive (plastic) surgeon repairs the wound, usually on the same day.

The reason Mohs surgery is so economical is that it can be performed under local anaesthetic in a procedure room, and it’s so effective because the surgeon removes as little healthy tissue as possible without the risk of the cancer recurring.