Informed consent: Mohs micrographic surgery

Mohs micrographic surgery is a unique technique used to treat skin cancer. The operation is named after its inventor, Dr. Fredrick Mohs. The surgical technique is effective for most skin cancers, but is used primarily to treat basal cell carcinomas and squamous cell carcinomas.

The Mohs surgery is conducted under local anesthesia, and, very infrequently, under general anesthesia. The operation involves resection of the affected tissue in thin layers throughout the perimeter and depth of the tissue. The resected tissue is mapped and processed in a laboratory adjacent to the operating room, using frozen sections, and examined under a microscope by the surgeon. Additional resections of any remnant cancer tissue are performed in the same manner, until healthy tissue is identified under microscopy.

When the resection is complete, the damaged region is reconstructed. Reconstruction is performed by suturing the skin side to side, if possible, or by moving skin from an adjacent area (flap), or by implanting skin removed from a remote site. Recovery time following the operation until removal of the sutures is usually 7 to 14 days.

A scar will remain at the surgical site. In many cases, it is delicate and nearly invisible, and in certain cases it is more apparent. The form of scarring is also dependent on each patient's skin structure and wound healing reaction.

The Mohs micrographic surgical technique results in the highest healing rates and lowest recurrence rates for the tumor, and enables maximal preservation of healthy tissue, thus reducing the potential for scarring or deformation.

The extent of resection and absent tissue following the primary operation cannot be estimated prior to surgery. Tissue loss is often much greater than the size of the tumor apparent to the eye before the primary operation.

Alternative treatment options relevant to these circumstances include: resection without microscopic control, freezing with liquid nitrogen, local radiation, or destruction of the tumor by laser, each with its own benefits and risks and the tests and procedures involved.

Side effects following the primary operation include bleeding into the tissue, redness, swelling, pain and discomfort.

In every case a scar will form in the area from which the lesion was removed.

Possible complications during the primary operation and following it include: local hemorrhage, local infection, opening of the sutures, non-merging of the flap or graft, a prominent scar, and pigmentation changes (loss of colour or excess colour in the treated area).

Injury to peripheral nerves is also possible, which in certain parts of the body may cause weakness and/or temporary or permanent numbness at the surgical site and/or in an adjacent area.

These and other complications not listed are not common.

The form of anesthesia is set in advance, local or general, and may combine types of anesthesia. It is finalised together with the anesthetist.

Under local anesthesia, consent is also given to intravenous sedation, with or without. The possible risks include allergic reactions of varying degrees to the anesthetic drugs, and possible complications of sedatives, which may rarely cause disturbances of breathing and of cardiac activity, mainly in patients with heart disease or a respiratory disorder.

If the decision is made to operate under general anesthesia, an explanation about the anesthesia is given by an anesthesiologist.

The operation and any other procedure will be performed by any designated person, according to the institutional procedures and directives, unless a particular surgeon was chosen and agreed in advance, as long as it is performed in keeping with the institution's standard degree of responsibility and in accordance with the law.

If the medical centre has a university affiliation, students may take part in the assessment and treatment, under full supervision.

The physician who performed the surgery may not be present at the time of discharge. In that case another physician on their behalf will carry out the discharge.