How is cutaneous Squamous Cell Carcinoma (cSCC) treated?

If your skin lesions are left untreated, they may continue to grow, which can cause damage to surrounding tissue. The cancer can even spread to other parts of your body and in rare cases, can lead to death.

There are several treatment options for cSCC. Which treatment option is best for you depends on the size, location and aggressiveness of the tumour. Treatment options may include:

Surgery

All stages of cSCC are usually treated with surgery. There is a very high rate of cure for cSCC with surgical treatment. The treatment option that is best for you will depend on the size, location and aggressiveness of the tumour. If your skin lesion is left untreated, it may continue to grow, which can cause damage to surrounding tissue. The cancer can even spread to other parts of your body and in rare cases, can lead to death. cSCC that has spread can now be treated with immunotherapy.

Surgical Treatments:

Simple Excision:

This procedure involves your doctor removing the cancerous tissue and a surrounding margin of healthy skin. In some cases, your doctor may recommend removing additional normal skin around the tumour. This is known as a wide excision. Simple excision is a standard procedure for squamous cell skin cancers.

Mohs Surgery:

Mohs surgery is most often conducted for cSCC on the head or neck. During this procedure, your doctor removes the cancerous tumour and some of the surrounding tissue underneath. Your doctor then examines the margins around the excised tissue under a microscope to see if there are any other cancerous cells remaining. The procedure is repeated until clear margins are obtained.

This procedure allows the surgeon to be sure that the entire growth is removed while avoiding removing an excessive amount of surrounding healthy skin.

This form of surgery has the highest rate of success in treating cSCC, and is often used to treat large, recurrent tumours or tumours located in difficult-to-treat areas such as the face, eyes, ears, nose, hands, feet and shins, sparing as much normal tissue as possible.

Superficial Treatments for Early Stage Disease

cSCC is usually treated with surgery. However, early stage cSCC is often treated effectively through topical treatments that treat the top layer of the skin. Treatments for early stage disease (cSCC in situ, Bowen’s disease) may include topical chemotherapy creams or gels, cryotherapy, or photodynamic therapy (PDT).

The treatment option that is best for you will depend on the size, location and aggressiveness of the tumour. If your skin lesion is left untreated, it may continue to grow, which can cause damage to surrounding tissue. The cancer can even spread to other parts of your body and in rare cases, can lead to death.

Local Treatments

Topical Chemotherapy:

These are medicines that are put directly on the skin as a cream or gel (called topical). The drugs most often used in topical treatment for cSCC are 5-FU (Efudex, Actikerall), ingenol mebutate (Picato) and imiquimod (Aldara, Zyclara). These drugs are used according to various protocols, as recommended by your health care provider.

When put directly on the skin, these topical chemotherapies kill tumor cells on or near the skin’s surface, but they can’t reach cancer cells deeper in the skin or cells that have spread to other organs. For this reason, they are generally used only for precancerous conditions such as actinic keratosis and for early stage superficial skin cancers.

Cryosurgery or Cryotherapy:

Cryosurgery for early stage in situ disease uses liquid nitrogen to freeze the cancerous cells. It burns during treatment, causing the area to blister and then scab over in 1 to 2 weeks.

Electrodesiccation and Curettage (ED and C):

ED and C treatment involves removing the surface of the visible tumour with a scraping instrument (curet) and then searing the base of the wound with an electric needle. This is intended to kill off any remaining cancer cells and help to stop the bleeding.

Photodynamic Therapy (PDT)

Photodynamic Therapy (PDT):

This treatment combines photosensitizing drugs and light to treat superficial skin cancers. During this procedure, a liquid or cream drug that makes cancer cells sensitive to light is applied to the skin. Following this, a light that destroys the cancer cells is shined on the prepped area

Radiation Therapy

This treatment uses high-energy beams to kill cancer cells or slow their growth by damaging the cancer cells’ DNA. Cancer cells whose DNA is damaged beyond repair will stop dividing or die. This may be an option for treating deeper tumours, or those that have a risk of becoming recurrent (coming back after treatment). It may also be used in people who are not candidates for surgery.

Intralesional Therapy

Intralesional treatment for cSCC involves injecting therapeutic agents directly into the tumor, serving as an alternative to surgery for patients with non-operatable, multiple, recurrent, slowly growing tumors. Common agents include 5-fluorouracil (5-FU) and methotrexate (MTX). There are emerging evidence supporting the use of intralesional immunotherapy and virotherapy.

Systemic Drug Therapy

Systemic drug therapy is often used in advanced or metastatic cases of cSCC. Systemic therapies are drugs that spread throughout the body to treat cancer cells wherever they may be. They have many different forms such as chemotherapy, targeted drugs, and immunotherapy.

Chemotherapy:

Chemotherapy has been used to treat cSCC, but it is not very effective and there is no standard chemotherapy regimen fornon-melanoma skin cancer.

Immunotherapy

Immunotherapies are a new class of drugs that have been developed to stimulate a person’s own immune system to recognize and destroy cancer cells. Immunotherapies act to release the brakes, or checkpoints, of the immune system, allowing it to mount a stronger and more effective attack against cancer cells. These drugs are usually given intravenously in hospital or specialized clinic.

Currently, the immune checkpoint inhibitor cemiplimab (Brand name Libtayo) was approved in Canada for the treatment of adult patients with metastatic or locally advanced cSCC who are not candidates for curative surgery or curative radiation.

Recently, new clinical trial data showed improved disease free survival (DFS) with preventive cemiplimab compared to placebo among patients with high risk cSCC post-surgery. This could be a treatment option for eligible patients’ post-surgical resection. Learn more about clinical trials.