If your dermatologist has given you a diagnosis of skin cancer, you might assume that surgery to remove it is in your future. But that’s not necessarily true.

Most skin cancer treatments do involve surgery, light therapy, or radiation. However, some topical and oral medications can also work on certain types of skin cancer. These noninvasive treatments can help you avoid scars and other side effects of more intense therapies.

A few topical medications treat certain types of skin cancer. The advantage to these drugs is that they don’t leave scars like surgery can. However, they’re only effective for precancerous growths or lesions and for early skin cancers that haven’t spread.

Imiquimod (Aldara, Zyclara) is a cream that treats small basal cell cancers and actinic keratosis — a precancerous skin condition. Aldara works by stimulating the immune system locally to attack the cancer. It can cure between 80 percent and 90 percent of superficial (not deep) basal cell cancers. You apply this cream to your skin once a day, a few times a week, for 6 to 12 weeks. Side effects include skin irritation and flu-like symptoms.

Fluorouracil (Efudex) is a type of chemotherapy cream that’s approved for small basal cell cancers and actinic keratosis. It kills cancerous and precancerous cells directly. You apply this cream twice a day for three to six weeks. Efudex can cause redness and irritation of the skin.

Two other topical drugs — diclofenac (Solaraze) and ingenol mebutate (Picato) — are approved to treat actinic keratosis. Solaraze is a nonsteroidal anti-inflammatory drug (NSAID) — part of the same drug class as ibuprofen and aspirin. Both of these medications can cause temporary redness, burning, and stinging of the skin.

Photodynamic therapy uses light to kill cancer cells in the surface layers of your skin. It treats actinic keratosis, as well as basal cell carcinoma and squamous cell cancer on the face and scalp. With basal cell cancer, the cure rates are between 70 percent and 90 percent. This treatment isn’t helpful for deeper skin cancers or for cancers that have spread.

Your doctor will give you photodynamic therapy in two stages. First, the doctor will apply a medication like aminolevulinic acid (ALA or Levulan) or methyl ester of ALA (Metvixia cream) to the abnormal growths on your skin. The cancer cells will absorb the cream, which will then activate the light.

A few hours later, your skin will be exposed to a special red or blue light for a few minutes. You’ll wear goggles to protect your eyes. Your skin might sting or burn temporarily from the light. The combination of the drug and the light produces a chemical that’s toxic to cancer cells, but isn’t harmful to surrounding healthy tissue.

The treated area will turn red and crusty before healing. It can take about four weeks for it to fully heal.

The advantages to photodynamic therapy are that it’s noninvasive, as well as relatively quick and easy. But, the drugs can make your skin very sensitive to the sun. You’ll need to stay out of direct sunlight or wear sun-protective clothing when you go outside.

Other side effects from photodynamic therapy include:

  • skin redness
  • swelling
  • blisters
  • itchiness
  • color changes
  • eczema or hives, if you’re allergic to the cream

Vismodegib (Erivedge) is a pill that treats basal cell carcinoma that has spread or come back after surgery. It’s also approved for use in people with skin cancer who aren’t candidates for surgery or radiation. Erivedge works by blocking an important step in the process skin cancer uses to grow and spread. Because this drug can cause severe birth defects, it isn’t recommended for women who are pregnant or who could become pregnant.

Sonidegib (Odomzo) is another, newer oral drug for advanced basal cell carcinoma. Like Erivedge, it’s recommended for people whose cancer has returned after treatment. It can also treat people who aren’t good candidates for other treatments. However, it can cause severe birth defects, as well as other side effects, like muscle pain and spasms.

Radiation therapy uses high-energy waves to kill cancer cells and stop them from multiplying. It’s used to treat basal cell and squamous cell skin cancers, and it may cure these cancers. For melanoma, radiation may be used together with surgery and other treatments.

External beam radiation is typically the method used to treat skin cancer. Radiation is delivered from a machine outside your body. With skin cancer, the beam usually doesn’t penetrate very deeply into your skin to avoid damaging healthy tissue. You’ll get radiation treatments five days a week for a few weeks.

Side effects of radiation include redness and irritation of the skin in the treated area. You might also lose hair in that area.

Noninvasive treatment may be an option for you depending on a number of factors. The type of skin cancer you have, the stage of the cancer, and your general health all play a role in the decision you and your doctor make. Talk to your dermatologist about these treatments to see if they’re a good fit for you.