Drug therapy for non-melanoma skin cancer

Drug therapy uses drugs to treat non-melanoma skin cancer. It is sometimes used to treat non-melanoma skin cancer. You may have drug therapy to:

• destroy cancer cells on the skin or in the body
• slow or stop the growth and spread of cancer
• shrink a tumour before other treatments such as surgery or radiation therapy (called neoadjuvant therapy)
• destroy cancer cells left behind after surgery (called adjuvant therapy)
• relieve or control symptoms of advanced non-melanoma skin cancer (called palliative therapy)

If you have drug therapy, your healthcare team will use what they know about the cancer and about your health to plan the drugs, doses and schedules.

Side effects of drug therapy will depend mainly on the type of drug or drug combination, the dose, how it's given and your overall health. Tell your healthcare team if you have side effects that you think might be from drug therapy. The sooner you tell them of any problems, the sooner they can suggest ways to help you deal with them.

Different types of drug therapy are used for non-melanoma skin cancer. Some drugs are given as topical therapy (applied directly on the skin) and some are systemic therapy (circulates throughout your body).

Topical therapy is a drug that is applied directly on the skin as a cream or ointment.

Imiquimod (Aldara, Zyclara) is a type of immunotherapy drug called an immune response modifier. It uses your immune system to help destroy cancer cells. It may be used to treat small, superficial basal cell carcinoma (BCC) on the neck, the central part of the body (called the trunk), arms or legs. It may also be used for squamous cell carcinoma (SCC) in situ.

Fluorouracil (also called 5-fluorouracil or 5-FU) is a chemotherapy drug used to treat a specific area on the skin. Topical 5-FU is mainly used for precancerous conditions of the skin such as actinic keratosis. It may also be used for superficial BCC or SCC in situ.

These drugs usually put on the growth or abnormal area once a day for several weeks.

Topical imiquimod and topical 5-FU may cause these side effects:

• skin problems in the treated area, such as redness and itching
• burning and pain in the treated area
• swelling (edema)
• discharge from the wound

Targeted therapy uses drugs to target specific molecules (such as proteins) on cancer cells or inside them. These molecules help send signals that tell cells to grow or divide. By targeting these molecules, the drugs stop the growth and spread of cancer cells and limit harm to normal cells. Targeted therapy may also be called molecular targeted therapy. It is a systemic therapy.

Vismodegib (Erivedge) is a targeted therapy drug called a hedgehog signalling pathway inhibitor. The hedgehog signalling pathway helps cells develop and grow. It is usually turned off (inactive) in adults. But sometimes changes (mutations) in certain proteins make the pathway and proteins too active. The proteins then send signals that cause BCC to develop, grow and spread quickly. Vismodegib targets the proteins and blocks the signals.

Sonidegib (Odomzo) is another hedgehog signalling pathway inhibitor that may be offered.

Vismodegib and sonidegib can be used to treat BCC that has grown into nearby areas (called locally advanced BCC) or BCC that has spread to other parts of the body (called metastatic BCC) when surgery or radiation therapy can't be used. These drugs are given daily as a pill by mouth (orally). They are usually given until the non-melanoma skin cancer no longer responds to them or unless the side effects outweigh the benefits of having the treatment.

Cetuximab (Erbitux) is a targeted therapy drug called an epidermal growth factor receptor (EGFR) inhibitor. EGFR is a receptor on the surface of cells that sends signals to cells that allow them to grow and divide. A mutation in the EGFR gene can cause cancer cells to grow and divide more than normal. Cetuximab targets and blocks the EGFR receptor. Cetuximab may be used for locally advanced or metastatic SCC if surgery can't be done. It may also be used after surgery as adjuvant therapy. Cetuximab is given through a needle into a vein (intravenously).

Find out more about targeted therapy. Ask your healthcare team questions about targeted therapy.

Vismodegib and sonidegib may cause these side effects:

• muscle and bone pain, including muscle cramps
• hair loss
• taste changes
• loss of appetite and weight loss
• fatigue
• nausea and vomiting
• diarrhea

Cetuximab may cause these side effects:

• skin problems, such as rash, itching and being more sensitive to the sun
• liver problems
• muscle weakness
• headache
• fatigue
• nausea
• loss of appetite
• diarrhea
• constipation
• fever

Immunotherapy helps to strengthen or restore the immune system's ability to fight cancer. This works to kill cancer cells and stop cancer cells from growing and spreading. Immunotherapy is a systemic therapy.

Cemiplimab (Libtayo) is an immunotherapy drug called an immune checkpoint inhibitor. The immune system normally stops itself from attacking normal cells in the body by using specific proteins called checkpoints. Checkpoints slow down or stop an immune system response. Some skin cancer cells sometimes use these checkpoints to hide and avoid being attacked by the immune system. Immune checkpoint inhibitors work by blocking the checkpoint proteins so immune system cells (called T-cells) attack and kill the cancer cells.

Pembrolizumab (Keytruda) is an immune checkpoint inhibitor that targets the PD-1 checkpoint protein.

Cemiplimab and pembrolizumab are used for locally advanced or metastatic SCC when surgery or radiation therapy can't be used. They are also used to treat locally advanced BCC that was already treated with a hedgehog pathway inhibitor.

Cemiplimab and pembrolizumab are given intravenously every 2 or 3 weeks. They are usually given until the cancer stops responding or unless the side effects outweigh the benefits of having the treatment.

Find out more about immunotherapy. Ask your healthcare team questions about immunotherapy.

Cemiplimab and pembrolizumab may cause these side effects:

• pain in the abdomen
• constipation
• loss of appetite
• cough
• diarrhea
• fatigue
• skin problems, such as a rash
• headaches
• liver problems

Chemotherapy uses drugs to destroy cancer cells. These drugs target rapidly dividing cells throughout the whole body. This means that chemotherapy kills cancer cells but it can also damage healthy cells.

With most types of chemotherapy, the drugs travel through the blood to reach and destroy cancer cells all over the body, including cells that may have broken away from the original (primary) tumour. This is called systemic therapy.

Systemic chemotherapy is usually only used for locally advanced or metastatic non-melanoma skin cancer. Some common chemotherapy drugs used are cisplatin and paclitaxel. These are given intravenously. For some cases of advanced or metastatic SCC, other drugs may be combined with chemotherapy, such as the immunotherapy drug called interferon alfa (Intron A, Wellferon) or retinoid drugs. There is no standard chemotherapy treatment plan for non-melanoma skin cancer.

Find out more about chemotherapy. Ask your healthcare team questions about chemotherapy.

Systemic chemotherapy may cause these side effects:

• nausea and vomiting
• fatigue
• low blood cell counts
• diarrhea
• kidney problems
• hearing problems, including ringing in the ears
• hair loss
• muscle and bone pain

Details on specific drugs change quite regularly. Find out more about sources of drug information and where to get details on specific drugs.