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:

Superficial Treatments

cSCC is usually treated with surgery. However, early stage cSCC is often treated effectively through superficial treatments that treat the top layer of the skin. Treatments for early stage (cSCC in situ, Bowen’s disease or stage T or 0) 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 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.

Topical Treatments

Topical Chemotherapy:

Topical Chemotherapy medicines 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 are typically applied to the skin once or twice a day for several weeks. When put directly on the skin, 5-FU kills tumor cells on or near the skin’s surface, but it can’t reach cancer cells deeper in the skin or those that have spread to other organs. For this reason, 5-FU is generally used only for precancerous conditions such as actinic keratosis and for early stage superficial skin cancers.

Cryosurgery or Cryotherapy:

Once the tumour has been removed, the base and edges of the biopsy site are treated with liquid nitrogen. This freezes the cancerous cells and 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 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.

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 low-risk squamous cell skin cancers.

Mohs Surgery:

During this procedure, your doctor removes the cancerous tumour layer by layer, examining each layer under a microscope until no abnormal cells remain. This procedure allows the surgeon to be sure that the entire growth is removed while avoiding taking 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.

Radiation Therapy

This treatment uses high-energy beams, to kill cancer cells or slow their growth by damaging the cancer cell’s 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. It may also be used in people who are not candidates for surgery.

Systemic Drug Therapy

Systemic drug therapy is currently used only in advanced or metastatic cases for squamous cell carcinoma. 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 there has been no standard chemotherapy treatment plan for non-melanoma skin cancer.[1]

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 of the immune system, allowing it to mount a stronger and more effective attack against cancer cells. These drugs are usually given in hospital or specialized clinic by intravenous.

Recently, the immunotherapy cemiplimab (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.[3]