side effects of EGFR Inhibitor

After Your Cancer Diagnosis: What To Know About The Side Effects of EGFR Inhibitor Drugs

Receiving a cancer diagnosis can be overwhelming, especially if you have a more aggressive type of cancer or discover it at a more advanced stage. 

After your diagnosis, you can expect to receive a comprehensive treatment plan that may include surgery, radiation therapy, chemotherapy and other targeted therapies depending on the type of cancer you have. If your cancer is more advanced or resistant to other drugs, you may be prescribed EGFR inhibitor drugs, which have proven to be effective in slowing the progression of several types of cancers, including lung cancer, colon cancer, breast cancer, thyroid cancer and pancreatic cancer.

Unfortunately, these drugs can come with uncomfortable side effects for patients. 

If you or someone you know is considering taking these drugs to treat cancer, here’s what you should know. 

When are EGFR inhibitor drugs prescribed for cancer patients?

Epidermal growth factor receptor (EGFR) is a protein that promotes cell growth. When an EGFR gene has a mutation, it can grow too much, causing cancer. EGFR inhibitor drugs are designed to slow down or stop cell growth in patients with this gene mutation. While they do not cure the cancer, they are used alongside other treatments, such as chemotherapy, to control the progression. 

These drugs are most commonly prescribed during or after: 

Treatment for non small-cell lung cancer 

About 10-15% of lung cancers are considered EGFR-positive, according to the American Lung Association. EGFR-positive lung cancer is more common in patients without a history of smoking. If your cancer is detected early and you’re eligible for surgery, you may be prescribed an EGFR inhibitor pill to keep it from coming back. EGFR inhibitors may also be prescribed to keep late-stage lung cancer from progressing. 

Colorectal cancer treatment

As many as 25% of colorectal cancer cases are diagnosed when they are already at an advanced stage, according to the National Library of Medicine. Because EGFRs play a role in as many as 25-82% of these cancers, your oncologist may prescribe EGFR inhibitors in addition to chemotherapy, surgery or nanotherapy that targets the tumor. 

Treatment for certain types of breast cancer

Certain types of breast cancer tend to have an overexpression of EGFRs, which can make them more aggressive and more difficult to treat. Research shows they contribute to about 14% of breast tumors and tend to be more common in hereditary breast cancer. EGFRs also tend to be overexpressed in triple negative breast cancer, which is characterized by a reduced expression of estrogen, progesterone and Her2 receptors. This type of breast cancer is more likely to spread quickly and be more resistant to cancer drugs. 

EGFR inhibitors can also reduce the risk of recurrence of early-stage breast cancer with human epidermal growth factor receptors known as HER2, which causes cells to grow and divide quickly.

Treating advanced drug-resistant thyroid cancer

Tyrosine kinase inhibitors (TKIs) are oral medications, such as levatinib, used to treat advanced thyroid cancer. However, some types of cancer are resistant to these treatments. Research has shown EGFR inhibitors may help patients overcome this resistance.

What are common EGFR inhibitor drugs?

As of 2021, 14 EGFR small-molecule inhibitors had been approved for cancer treatment, according to the National Library of Medicine.

Common names include:

Tarceva

Known by the generic name erlotinib, Tarceva is often used to treat lung cancer and pancreatic cancer that has spread to other parts of the body.

Tagrisso 

Known by the generic name osimertinib, Tagrisso has been shown to improve the median overall survival rate for patients with Stage 4 lung cancer. 

Nerlynx

Known in its generic form as neratinib, Nerlynx can help reduce the recurrence of early-stage HER2-positive breast cancer. 

Iressa

Iressa, or gefitinib, has been FDA-approved to treat patients with advanced non-small cell lung cancer. 

Erbitux

Known in its generic form as cetuximab, Erbitux treats metastatic colorectal cancer. It may be prescribed in combination with other medications as a first line of defense or when other chemotherapy drugs have failed.

Vectibix 

Vectibix is another brand of cetuximab that treats patients with metastatic colorectal cancer. 

What are the side effects of EGFR inhibitor drugs?

While EGFR inhibitor drugs play an important role in cancer treatment, they can lead to painful side effects.

Frequently, side effects are dermatological, affecting the hair and the skin – ranging from excessively dry skin to painful rashes and blisters. Common side effects include:

  • Folliculitis – Presenting in 40-85% of patients, inflamed hair follicles often occur in the first 10 days of treatment. The condition most frequently occurs on the T-zone of the face but can also affect the chest, back, scalp and pubic region. Folliculitis often occurs with cetuximab.
  • Alopecia/trichomegaly – Changes in the hair chemistry, including hair loss similar to male pattern balding, can accompany TKI use 2-3 months after beginning the medication.
  • Paronychia and splinter hemorrhages – Inflammation of the nail folds, paronychia affects fingers more frequently than toes and can be incredibly painful. Splinter hemorrhages are often side effects of small molecule kinase inhibitors.
  • Rashes and swollen hands/feet – The EGFR inhibitor drugs imatinib and sorafenib can induce a red facial rash. Some patients experience swelling around the lips and mouth, called stomatitis. The painful swelling of palms and soles, known as acral erythema, is often a side effect of sorafenib and sunitinib.

The reason skin changes are the most prevalent side effects of EGFR inhibitor drugs is because these are targeted drug therapies. In the quest to stop the cancer cells from growing and dividing, the drug affects the skin cells that already have a higher level of EGFR naturally. The drug can’t just inhibit the epidermal growth factor receptor for the cancer cells – all EGFR are affected, no longer triggered to divide and grow normally. This makes it more challenging to retain moisture, and dry, scaly, and rashy skin results.

Treating EGFR side effects

While EGFR inhibitor drugs can be life-saving treatments, patients shouldn’t have to worry that the drugs that save their lives are also going to produce miserable side effects. 

Physicians may recommend topical creams or antihistamines to control the itching and rashes that can occur as a result. They may also prescribe acne medications, such as benzoyl peroxide gels, or oral antibiotics, such as tetracycline. However, there are no FDA-approved medications designed specifically to treat EGFR side effects. Clinical trial sponsors are testing investigational topical medications to minimize these painful side effects. If you are receiving treatment for cancer where EGFR is a factor but are not yet taking EGFR inhibitors, you may be eligible to participate.  To learn more about clinical trials to treat the side effects of EGFR inhibitors, search the Neighborhood Trials app for a trial near you.