Targeted Therapy: A Better Approach For Cancer Treatment

07 May,2024

Cancer begins when a cell's genetic instructions about division/multiplication are modified. Usually, cells follow these instructions and multiply in a standard way. However, in cancer, the altered genetic instructions lead to uncontrolled division and the formation of tumors. 

Targeted therapy is a treatment approach in which healthcare providers identify specific targets in cancer cells and use drugs customized to those cells' genetic instructions. These tailor-made drugs can either destroy cancer cells entirely or prevent them from receiving the instructions they need to continue growing.

Targeted therapy has revolutionized cancer treatment. The FDA has approved targeted therapy for over 15 different types of cancer. If you are fascinated by this new treatment and want to know more, you have landed on the right page. This blog aims to educate people about targeted therapy, how it works, and what kind of cancer it treats. 

What is Targeted Therapy?

There are many types of cancer, and not all cells behave similarly. For example, breast and colon cancer cells have different gene changes that cause them to grow and spread. The environment where cancer cells grow can differ from one person to another. Some cancers have specific proteins or enzymes that send signals telling the cancer cells to grow and copy themselves.

Scientists have developed drugs that target these proteins or enzymes and block their signals. These drugs can potentially prevent cancer cells from growing or signal them to self-destruct, which can be helpful in cancer treatment.

Targeted therapy is a cancer treatment that oncologists can use before or after surgery, as well as during the later stages of cancer treatment. It is also used as a long-term treatment to try and prevent cancer from coming back or to control its growth. 

The method and location of administering targeted drugs to cancer patients depend on several factors, including clinical considerations and personal preferences. 

• Targeted drugs can be given orally, usually in the form of a pill, capsule, or liquid that can be taken at home. 
• They can also be delivered through an injection, which is administered through a needle into a vein, muscle, or under the skin. 
• Additionally, targeted drugs can be given by infusion, which is delivered into a vein through an intravenous drip. It may take several hours to complete.

How Does Targeted Therapy Work?

Targeted therapy as a cancer treatment targets specific proteins that promote tumor growth and spread in the body. Unlike chemotherapy, which tends to kill all rapidly dividing cells, targeted therapy is more selective in its approach. This treatment approach interferes with the specific proteins responsible for cancer growth and prevents them from functioning correctly. The following mechanisms provide an overview of how targeted therapy treats cancer.

Boosts Immune System

• Cancer cells can survive and grow by hiding themselves from the immune system. 
• However, specific targeted therapies can help identify and label cancer cells, making it easier for the immune system to locate and destroy them. 
• Additionally, some targeted therapies can enhance the immune system's efficacy, making it more effective in fighting cancer.

Blocks Growth Signals

• Targeted therapy aims to prevent cancer cells from growing and dividing uncontrollably. It disrupts the signals that cause cancer cells to grow without order. 
• Healthy cells in your body divide only when they receive signals to do so. These signals attach to proteins on the cell surface, instructing the cells to divide and create new cells as needed by the body. 
• However, cancer cells can behave differently. Cancer cells have alterations in the proteins on their surface. These proteins tell cells to divide regardless of whether signals are present. 
• Targeted therapies can interfere with these proteins, preventing them from instructing the cells to divide and thus slowing down the cancer's uncontrolled growth.

Stops Blood Vessel Formation 

• Tumors need new blood vessels to grow larger. This process, called angiogenesis, happens when the tumor sends signals. 
• Some drugs, called angiogenesis inhibitors, stop these signals and prevent the formation of blood vessels. Without a proper blood supply, tumors are forced to stay small. 
• If a tumor already has a blood supply, these drugs can cause the blood vessels to die, which makes the tumor shrink.

Delivers Toxins

• Monoclonal antibodies are a class of targeted therapy drugs that can be combined with chemotherapy drugs, toxins, or radiation to kill cancer cells. 
• These antibodies attach to specific targets on the cancer cells and deliver toxins to them. It leads to cancer cell death. 
• This selective process means only the cancer cells are targeted and destroyed. Cells without the target on their surface will not be affected.

Triggers Cell Death

• Healthy cells are programmed to die in an organized manner when they are no longer needed or become damaged. However, cancer cells have evolved ways of avoiding this process. 
• Fortunately, targeted therapies have been developed to cause cancer cells to go through programmed cell death (apoptosis). 
• By forcefully inducing apoptosis, these therapies help eliminate cancer cells from the body, thereby promoting healthy cellular regeneration and preventing the spread of cancer.

Blocks Hormones

• Prostate and breast cancers require certain hormones to grow. However, hormone therapies offer a targeted approach to treating these types of cancers, with two different methods available. 
• Some hormone therapies can stop your body from producing certain hormones, while others can stop those hormones from affecting your cells, including cancerous ones. 
• Hormone therapies are effective because they work by disrupting the hormones that cancer cells need to grow and divide.

Which Cancers Does Targeted Therapy Treat?

Researchers have developed over 80 targeted therapy drugs to treat 15+ types of cancers. Further, targeted therapies have been developed to treat different mutations in the same kind of cancer. Oncologists are using targeted therapy to treat:

• Brain tumors (glioblastoma, neuroblastoma)
• Blood cancer (leukemia, lymphoma, multiple myeloma)
• Bone cancer
• Breast cancer (HER2-positive breast cancer, triple-negative breast cancer)
• GI cancer (cancer of the esophagus, colorectal, stomach, liver, pancreas, gall bladder)
• Small and non-small cell lung cancer
• Skin cancer (squamous cell skin cancer, melanoma)
• Thyroid cancer (medullary thyroid cancer, anaplastic thyroid cancer, follicular thyroid cancer)
• Kidney cancer
• Prostate cancer
• Cervical cancer
• Endometrial cancer
• Bladder cancer

How Do Oncologists Find Targets?

Knowing precisely where to aim is essential to help oncologists decide whether targeted cancer therapy is appropriate. Luckily, there are several tests available to assist in precision medicine. These tests can help determine which DNA mutation is driving the cancer's behavior and suggest the appropriate therapy, including:

• Advanced Genomic Testing: This analysis scans the tumor's genetic profile for specific mutations that may drive its growth, progression, or other behaviors. When a known mutation is found, it is matched to a particular drug therapy targeting that mutation.
• Pathology Tests: These tests examine tissue, blood, or stool samples. Pathologists may identify potential therapy targets by searching for mutant proteins or an overabundance of proteins in cancer cells.
• Genetic Testing: These tests determine whether a patient has a hereditary gene mutation linked to cancer. Knowing this information can help determine the best course of action. 

By utilizing these tests, oncologists can provide patients with more personalized, effective, and safe cancer treatment.

How Does Targeted Therapy Differ From Chemotherapy?

Chemotherapy drugs are medications that target all cells that multiply quickly. They work by eliminating cancer cells. However, they can also cause damage to the healthy cells that multiply rapidly, such as those in the bone marrow, mouth, stomach, or hair. It leads to unpleasant side effects such as painful mouth ulcers, persistent nausea, infections, hair loss, and low blood cell counts.

Targeted therapy drugs, on the other hand, work differently. They focus on cancer cells while minimizing harm to healthy cells. The side effects are usually less severe than those of chemotherapy drugs.

Does Targeted Therapy Have Side Effects?

Targeted therapies are cancer treatments that explicitly target cancer cells while sparing healthy ones. They result in fewer side effects than conventional treatments like chemotherapy. However, targeted therapy may also alter cell function, which can lead to side effects that require monitoring and management.

One of the most challenging side effects of targeted therapy is skin problems. These occur because the treatment attacks the same growth factors and blood vessels your skin needs to stay healthy. Some common skin problems to watch out for include:

• Painful, itchy rashes 
• Severe sunburn
• Extreme sensitivity to sunlight
• Dry skin
• Sores on your scalp, hair loss, or baldness
• Red, swollen eyelids 
• Swollen, painful sores on your toenails and fingernails 

Skin damage is the most common but not the only side effect of targeted therapy. Liver problems and diarrhea are also observed in a few patients receiving targeted therapy.  Other side effects include:

• High blood pressure
• Slow wound healing
• Bleeding and blood clotting disorders
• Autoimmune reactions
• Heart problems
• Swelling
• Nausea and Vomiting
• Fatigue

It's crucial to stay informed about the side effects of cancer treatments and find ways to manage them. By working closely with your oncologist, you can take steps to minimize discomfort and have a more positive treatment experience.

What Questions Should You Ask Your Oncologist Before Receiving Targeted Therapy?

When it comes to cancer treatment, having a clear understanding of the options available is essential for successful results. Establishing trust between patients and doctors is crucial for positive outcomes. Talking to your healthcare team about targeted therapy as a recommended part of your cancer treatment plan is essential. Asking the right questions can help you make informed decisions about your treatment plan. 

Confused about what to ask before getting targeted therapy? To help you get started, here are some questions you might want to consider asking your healthcare team:

• What type of targeted therapy do you recommend, and why is this the best option for me?
• What are the goals of this treatment, and how will it help me?
• Will targeted therapy be the only treatment, or will other treatments be included in the cancer treatment plan?
• How will the treatment be administered, and where will it take place?
• How often will I need to undergo this treatment, and for how long?
• What are the short-term side effects of targeted therapy, and how will they be managed?
• Whom should I contact if I experience any side effects, and how soon should I contact them?
• How will this treatment affect my everyday life, and will I be able to work, exercise, and do my usual activities?
• What long-term side effects does targeted therapy have?
• How do I know if targeted therapy is working for me?
• Will I need any scans or tests before, during, or after the treatment?

Remember, your healthcare team is there to help you, and answering these questions will give you a better understanding of what to expect during the treatment process. 

Takeaway

Cancer is one of the most challenging health problems. The complexity and diversity of cancer cell characteristics make traditional treatments difficult. However, targeted therapies have revolutionized cancer treatment. They represent a significant improvement in cancer treatment. Compared to chemotherapy, it offers a more precise approach that can yield better results and fewer side effects. If you're dealing with cancer, it is crucial to discuss targeted therapy with your doctor to see if it is the right course of action for you.