Targeted Therapy for Lung Cancer

Targeted therapy is a recent innovation in the war on lung and other cancers. Targeted-therapy drugs exploit specific mutations associated with some cancer cells to stop their growth, reproduction, and spread. In this way they operate differently than chemotherapy drugs, by bottling up cancer rather than simply destroying it. In the right circumstances, targeted therapy can be a highly effective means of stopping cancer, often, though not always, with fewer side effects than traditional chemotherapy. Its current focus is in combating advanced cancers, especially those tumors that have developed a tolerance for other types of medication.

How Does Targeted Therapy for Lung Cancer Work?

Your body is made up of cells, which are, in turn, made up of genes. Genes create the proteins that drive a cell’s operation. If a gene mutates, then the proteins it produces will stop supporting the cell’s proper functioning. Cells with mutations become cancers, reproducing rapidly and interfering with normal physiological processes. A mass of cancerous cells is a called a tumor. 

Rather than killing the cell outright, targeted-therapy drugs immobilize a cancer by attacking the mutation that’s causing abnormal behavior. Alternatively, they might neutralize some element in the cancer’s environment that’s encouraging its growth and spread. You can think of this as punishing cancer cells by putting them in a permanent “time-out”. The specificity of this approach – zeroing in on particular mutations or conditions rather than any rapidly reproducing cell, whether malignant or healthy – is why targeted therapy is also known as precision medicine.

The upside of precision medicine is a decrease in unintended side effects. The downside is that not every cancer cell responds to a targeted-therapy drug. That’s why your oncologist will conduct a genetic analysis of your lung cancer before proposing a targeted-therapy treatment. He or she will be looking for genetic evidence, called a biomarker, that a particular mutation is present in your cancer cells, which can be exploited by a targeted-therapy drug. Even this is no guarantee of success, as cancer cells have defenses of their own, oftentimes mutating until they reach a new form that is no longer affected by the drug. 

What Are the Targeted Therapies for Lung Cancer?

There are a variety of targeted-therapy drugs now in use with lung cancer. Below is a brief overview of the primary types:

• Angiogenesis inhibitors: Angiogenesis is the medical term for the body’s creation of new blood vessels. A cancer cell requires food energy like any other and must therefore have access to the blood supply. Angiogenesis inhibitors stop the growth of new vessels in the vicinity of the cancer, helping to starve it.
• EGFR inhibitors: Epidermal growth factor receptor (EGFR) is a protein that assists in cell growth and division. EGFR inhibitors use a variety of chemical means to prevent the EGFR protein from facilitating cellular reproduction.
• ALK inhibitors: ALK is another gene that, in a mutated form, encourages rapid cell growth and reproduction. ALK inhibitors target the mutant version of the gene.
• BRAF and MEK inhibitors: Two more mutated genes that respond to targeted-therapy drugs are BRAK and MEK.
• Targeted-therapy medications are most frequently used in treating non-small cell lung cancers. Treatment of small cell lung cancers is less common.

How Do I Prepare for Lung Cancer Targeted Therapy?

If your physician determines that targeted therapy is appropriate for you, there are several steps you can take to help prepare yourself for treatment:

• Maintain your health: You’re already fighting cancer; don’t make matters worse by neglecting your overall health. Remain active, eat well, get rest, and limit stress.
• Get ready for the side effects: Know what to expect and how to respond if side effects occur.
• Arrange for help from family members, friends, and colleagues: There will be times when you’re unable to maintain a normal level of activity. Plan ahead by having loved ones and others cover for you.
• Provide detailed information to your physician about current medications and other supplements: This is necessary to avoid potential interactions that might reduce the effectiveness of your lung cancer drugs.
• Develop a treatment routine: You may be limited in what you are allowed to eat and drink on the days you’re receiving therapy. You’ll want to have friends or family members at hand to assist in practical matters like driving and to offer comfort and support.

Targeted-therapy medications are typically given intravenously, either by injection or infusion (that is, by drip method via specially designed IV devices). Some drugs are available in pill form. Delivery can take place in a doctor’s office, hospital, outpatient facility, or cancer-treatment clinic. Most targeted therapy is provided in cycles, with periods of treatment followed by periods without, especially if it’s being administered in conjunction with a chemotherapy drug. Depending on the nature and circumstances of the therapy, treatment periods can run from a couple of weeks to as many as six months in duration.

You’ll see your physician regularly after completing targeted therapy for lung cancer. He or she will evaluate the effectiveness of your treatment. This process will continue indefinitely. If the treatment is unsuccessful or your cancer returns, your physician will devise a new plan for addressing it.

What Are the Side Effects of Targeted Therapy for Lung Cancer?

Targeted therapy tends to produce fewer or less severe side effects than chemo but it isn’t without negative effects. Depending on the type of medication and other factors, you may experience one or more of the following during treatment:

• Fatigue and anemia
• Nausea and vomiting
• Bleeding
• High blood pressure
• Headaches and fevers
• Loss of appetite and weight loss
• Oral sores
• Allergic reactions
• Diarrhea or constipation
• Rashes, itchiness, and other skin problems
• Eyesight issues
• Hair loss
• Achy joints

More serious side effects include blood clots, skin cancers, nerve damage, heart arrhythmias, and other major organ problems.