Non-surgical Local Treatments for Basal and Squamous Cell Skin Cancers

Cryotherapy, photodynamic therapy, topical chemotherapy, or other local treatments might be options to treat basal and squamous cell skin cancers (or pre-cancers) that haven't spread beyond the skin.

These are called local treatments because they only affect the area being treated. Some of these techniques might be described as types of surgery because they destroy a targeted area of body tissue. But these techniques are different from surgery because they don’t use scalpels or cut into the skin. (Radiation therapy is also a type of local treatment.)

Cryotherapy (cryosurgery)

Cryotherapy is used most often for pre-cancerous skin conditions such as actinic keratosis. It might also be used for squamous cell carcinoma in situ (Bowen disease) or for small basal cell and squamous cell carcinomas.

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.

After the dead area of skin thaws, it will swell, blister and crust over. The treated area may 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 actinic keratoses. It might also be an option to treat some small, low risk basal cell skin cancers, as well as 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(s), which kills the cells. Another option to activate the drug, especially when large areas need to be treated, is to have the person go out into the sunlight for a specific amount of time (known as daylight PDT).

PDT can cause redness and swelling on the skin where it is used. Another possible side effect of PDT is that it can make a person’s skin very sensitive to sunlight for some time, so precautions may be needed to avoid severe burns.

To learn more about this technique, see Photodynamic Therapy.

Topical chemotherapy

Chemotherapy (chemo) uses drugs that kill cancer cells. Topical chemotherapy 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 as an IV into a vein.

5-fluorouracil (5-FU): The drug most often used in topical treatment of actinic keratoses, as well as some basal and squamous cell skin cancers, is 5-FU (with brand names such as Efudex, Carac, and Fluoroplex). It is typically applied to the skin once or twice a day for several weeks. Sometimes it might be used along with calcipotriol (calcipotriene), a drug related to vitamin D, which could shorten the length of treatment to days instead of 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 parts of the body. For this reason, topical 5-FU is generally used only for pre-cancerous conditions such as actinic keratosis and for some very superficial skin cancers (cancers that only affect the surface of the skin).

Because the drug is only applied to the skin, it doesn’t spread throughout the body, so it doesn’t cause the same side effects as systemic chemotherapy (treatment that affects the whole body). But it does make the treated skin red and very sensitive for a few weeks. Other topical medicines can be used to help relieve this, if needed. 5-FU can also make the skin more sensitive to sunlight, so treated areas must be protected from the sun to prevent sunburn for a few weeks after treatment.

A very small portion of people have a condition called DPD deficiency, which makes it hard for their bodies to break down and get rid of 5-FU. This can result in serious or even life-threatening side effects. If you are applying 5-FU and have any reactions beyond those you were told to expect on your skin, call your doctor or nurse right away.

Tirbanibulin (Klisyri): This chemo drug comes in an ointment that can be used to treat actinic keratoses on the face or scalp. It is usually applied to the skin once a day for 5 days. It’s important to avoid getting this drug in or near your eyes or mouth.

The most common side effects of this drug include itching or pain in the treatment area. Some people might have more serious skin reactions, such as severe redness or swelling in the area, flaking, scaling, peeling, or crusting of the skin, blisters, pus, sores, or breakdown of the skin.

Diclofenac (Solaraze): A gel containing the drug diclofenac is sometimes used to treat actinic keratoses. This drug is part of a group of drugs called nonsteroidal anti-inflammatory drugs (NSAIDs), which includes aspirin and ibuprofen. The gel is usually applied twice daily for 2 or 3 months. It may cause less severe skin reactions than the chemo drugs above, but it can also take longer to work.

Immune response modifiers

Some drugs can boost the body’s immune response against the cancer, causing it to shrink and go away.

Imiquimod (Zyclara) is a cream that can be applied to actinic keratoses and some very early basal cell cancers. 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. Like other topical products, it can cause severe skin reactions in some people. It can also cause flu-like symptoms.

Laser surgery

This approach uses a beam of laser light to destroy the top layers of the skin. It might be an option for actinic keratosis, squamous cell carcinoma in situ (Bowen disease), or for very superficial basal cell cancers (those only on the surface of the skin). It’s not yet known if 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.