What a Mohs Surgeon sees under the Microscope

Mohs surgery is a labour-intensive process that takes time. The day may be long and boring for the patient but it is a very busy day for the Mohs surgeon. Your Mohs surgeon juggles removal of the tumour, examination of the tumour specimen under the microscope, and repair of the skin when the tumour has been successfully removed.

If you have ever wondered what a Mohs surgeon looks for under a microscope, here’s a preview. The American College of Mohs Surgery (ACMS) fellowship program ensures that each Mohs surgeon is trained to a high level. Distinguishing between normal and abnormal cells may be a challenge.

Here are some examples:

Basal cell carcinomas

Basal cell carcinomas are the most common type of skin cancer in New Zealand. While there are numerous subtypes of basal cell carcinoma, there are two key, common types:

Nodular basal cell carcinoma

View of a Nodular BCC under a microscope after it has been taken and put on slides during Mohs surgery.
Nodular basal cell carcinoma

Notice how subtle the tumour can be.

The following picture is of a benign hair follicle tumour called a tumour of follicular infundibulum. It takes a sharp eye to pick out the difference!

View of a follicular infundibulum BCC under a microscope after it has been taken and put on slides during Mohs surgery.
Tumour of the follicular infundibulum

Infiltrative basal cell carcinoma

View of an infiltrative BCC under a microscope after it has been taken and put on slides during Mohs surgery.
Infiltrative basal cell carcinoma BCC

This sub-type of basal cell carcinoma is known for its strands that look like tongues. This is an aggressive form of basal cell carcinoma.

Squamous cell carcinoma

Squamous cell carcinomas (SCCs) are an aggressive form of skin cancer that has the potential to metastasize (spread to other areas of the body). It is characterised by pleomorphic cells (variability in the size, shape, and texture of cells) which are eosinophilic (pink).

View of a SCC under a microscope after it has been taken and put on slides during Mohs surgery.
Squamous cell carcinoma

Experience Matters

It takes practice to be good at picking out a tumour under the microscope. Experience matters. At Skintel your surgeon has had thousands of hours of training equating to viewing more than 10,000 slides and counting!