Mohs surgery: fewer relapses and smaller scars

Mohs surgery is a surgical procedure to remove white skin cancer. The removed tissue is examined microscopically at the edges of the incision. If tumor remnants are still visible, targeted follow-up surgery is performed – step by step, until no more tumor is detectable.

In classic excision, the tumor is usually removed with a safety margin. In Mohs surgery, the tissue is removed as sparingly as possible and the margin is controlled. The aim is to remove as little healthy tissue as possible while still completely eliminating the tumor.

There are two main advantages: the risk of relapse may be lower and often less healthy tissue needs to be removed. Depending on the situation, this can improve the esthetic result.

It is particularly suitable for infiltrative tumors (with extensions) and in situations where tissue preservation is particularly important – for example on the face, nose, lips, ears or other functionally or aesthetically sensitive areas. Whether Mohs is appropriate depends on the tumor type, histological findings and location.

Depending on the findings, Mohs can be used for certain forms of basal cell carcinomas (basal cell carcinomas) and squamous cell carcinomas (spinaliomas), for example – especially if they grow infiltratively or if there is an increased risk of recurrence.

The tumor is usually removed under local anesthesia. The tissue at the edges of the incision is then examined microscopically. If tumor remnants are found, resection is performed at precisely this point with millimeter precision. These steps are repeated until the tumor is completely removed.

This can vary because the operation and microscopic control can be carried out in several stages. The procedure is often completed in at least two operations in one morning, in some cases it takes longer – depending on how many control steps are required.

Mohs surgery is often performed on an outpatient basis. The treatment team will clarify in advance whether outpatient treatment is possible in your case.

During the procedure, the local anesthetic usually ensures that you do not feel any pain. A feeling of pressure or tension may be possible. Depending on the location, you may experience soreness or tightness after the procedure; the team will advise you on suitable pain treatment.

Depending on the size and location, the wound is sutured directly, reconstructed or – in selected cases – left open to heal. In the case of complex localizations, collaboration with other specialties may be useful.

Scars cannot be completely avoided during surgery. Since as little healthy tissue as possible is removed with Mohs, the cosmetic result can be more favorable in many cases. The final appearance of the scar depends, among other things, on the location, tumor size, wound closure and individual healing.

As with any operation, bleeding, infection, impaired wound healing, temporary swelling or changes in sensitivity may occur. The treatment team will inform you individually about the risks and what to do after the procedure.

You will be given specific instructions in advance; as a rule, you do not need to be sober. If you are taking blood-thinning medication, please discuss this at an early stage – you should only make changes after consulting your doctor.

You will receive instructions on wound care and check-up appointments. In addition, regular skin checks are important because people with white skin cancer may have an increased risk of further skin tumors.

If Mohs surgery is medically indicated, the costs are usually covered by compulsory health insurance (depending on the deductible and excess). The exact clarification takes place during planning and administration.

Depending on the procedure, a referral from your general practitioner or a dermatologist may be advisable. The dermatology clinic will inform you about the appropriate procedure and the required documents (e.g. the histology report).