Non-surgical Local Treatments for Squamous Cell Carcinoma of the Skin

Cryotherapy, photodynamic therapy, topical chemotherapy, or other local treatments might be options to treat some squamous cell skin precancers or small squamous cell carcinomas (SCCs) that are at low risk for coming back, especially in people who can’t have or don’t want surgery.

These are called local treatments because they only affect the area being treated. Radiation therapy, another type of local treatment, is discussed separately.

Cryotherapy (cryosurgery)

Cryotherapy is the use of extreme cold to destroy tumors. It is used most often for skin precancers called actinic keratoses. It might also be an option for:

• Squamous cell carcinoma in situ, also called Bowen disease (very early squamous cell skin cancer)
• Small, well-defined squamous cell cancers that are at low risk for coming back

For this treatment, the doctor applies liquid nitrogen to the tumor to freeze and kill the cells. This is often repeated a couple of times in the same office visit.

Possible side effects

After the dead area of skin thaws, it will swell, blister, and crust over. The treated area might have fluid draining from it for a while, and it might take a month or two to heal. It will leave a scar, and the area might have less color after treatment.

Photodynamic therapy (PDT)

PDT can be used to treat skin precancers called actinic keratoses. It might also be an option to treat some very early forms of squamous cell cancer, known as squamous cell carcinoma in situ, or Bowen disease.

For this treatment, a drug is applied to the skin as a gel or liquid. The drug collects in the tumor cells over several hours, where it is converted to a different chemical that makes the cells very sensitive to certain types of light. A special light source is then focused on the tumor, which kills the cells.

When large areas need to be treated, daylight PDT, where the person goes out into the sunlight for a specific amount of time, might be an option.

Possible side effects

PDT can cause redness and swelling on the skin where it is used. PDT might also make a person’s skin very sensitive to sunlight for some time, so precautions might be needed to avoid severe burns.

Topical chemotherapy

Topical chemotherapy (chemo) means that an anti-cancer medicine is put directly on the skin, usually in a cream or ointment, rather than being taken by mouth or given into a vein (IV).

Imiquimod

Imiquimod (Zyclara) is a cream that can be applied to actinic keratoses. It causes the immune system to react to the skin lesion and destroy it. It’s typically applied at least a few times a week for several weeks, although schedules can vary.

Possible side effects

This drug irritates the skin, which might lead to itching, burning, redness, swelling, scabbing, crusting, or pain in the area. It can also make the skin more sensitive to sunlight, so treated areas should be protected from the sun to prevent sunburn for a few weeks after treatment. This drug can also cause flu-like symptoms in some people. The skin in the area being treated might also lose its pigment and become lighter in color.

Laser therapy (laser resurfacing)

This approach uses a beam of laser light to destroy the top layers of the skin. It might be an option for actinic keratosis or squamous cell carcinoma in situ (Bowen disease). It’s not yet known whether this type of treatment is as effective as standard methods of treatment, and it’s not widely used.

Chemical peeling

For this treatment, the doctor applies a chemical such as trichloroacetic acid (TCA) to the skin tumor, killing the tumor cells. This can lead to redness and peeling of the skin over the course of several days. This approach is sometimes used to treat actinic keratosis.