HOW DOES RADIATION THERAPY WORK? :  PRINCIPLES, BENEFITS & CHALLENGES.

Radiation therapy is a cancer treatment that uses high-energy waves to damage or destroy cancer cells. The waves stop cancer cells from growing and making more cancer cells by affecting the DNA inside of them. However, it can also damage some normal cells in the process. Radiation therapy can be given externally or internally, depending on the type, location and stage of cancer.

At CHECKUP CANCER, a company that provides comprehensive oncology services, we want to share some information and raise awareness about radiation therapy for cancer among the general public of India. In this blogpost, we will discuss the benefits and challenges of radiation therapy, and how it can help people with cancer.

## How does radiation therapy work?

Radiation therapy uses high-energy particles or waves, such as x-rays, gamma rays, electron beams, or protons, to destroy or damage cancer cells. Your cells normally grow and divide to form new cells. But cancer cells grow and divide faster than most normal cells.

Radiation works by making small breaks in the DNA inside cells. DNA is the molecule that carries the instructions for how cells function. When the DNA is damaged, the cells cannot follow the normal instructions and may die or stop dividing.

Radiation therapy can be given in different ways, depending on the type and location of cancer, the size and shape of the tumor, and your overall health and preferences. The main types of radiation therapy are external beam radiation therapy and internal radiation therapy.

## What are the types of radiation therapy?

  • External beam radiation therapy

External beam radiation therapy (EBRT) is the most common type of radiation therapy for cancer. It involves a machine that delivers high-energy beams from outside the body to the tumor site. The machine is called a linear accelerator or LINAC.

The beams are shaped and aimed precisely at the tumor, while avoiding or minimizing exposure to nearby healthy tissues. The treatment is painless and usually lasts a few minutes per session. You may need to have several sessions over a period of weeks or months.

There are different techniques of EBRT, such as:

3-dimensional conformal radiation therapy (3D-CRT): This technique uses a computer to create a 3D image of the tumor and surrounding organs. The beams are shaped to match the tumor and deliver a uniform dose of radiation.

Intensity-modulated radiation therapy (IMRT): This technique uses a computer to adjust the intensity of each beam segment. This allows for more precise delivery of radiation and sparing of normal tissues.

Image-guided radiation therapy (IGRT): This technique uses imaging tests, such as CT scans or ultrasound, before or during each treatment session. This helps to verify the position of the tumor and adjust the beams accordingly.

Stereotactic radiosurgery (SRS) or stereotactic body radiation therapy (SBRT): These techniques use very high doses of radiation delivered in one or a few sessions. They are used for small tumors in certain parts of the body, such as the brain, lung, liver or spine.

Proton therapy: This technique uses protons instead of x-rays or gamma rays. Protons are positively charged particles that can be controlled more precisely than other types of radiation. They deposit most of their energy at a specific depth in the tissue, which reduces damage to normal tissues.

  • Internal radiation therapy (Brachytherapy)

Internal radiation therapy (IRT) is also known as brachytherapy. It involves placing a radioactive source inside or near the tumor site. The source can be in different forms, such as wires, seeds, pellets, capsules or liquids.

The radioactive source emits radiation that travels a short distance in the body. This allows for a high dose of radiation to be delivered to the tumor while limiting exposure to normal tissues. The source can be placed temporarily or permanently, depending on the type and stage of cancer.

There are different techniques of IRT, such as:

Intracavitary brachytherapy: This technique involves placing the radioactive source in a body cavity, such as the uterus, cervix, vagina or esophagus.

Interstitial brachytherapy: This technique involves placing the radioactive source directly into the tumor tissue, such as in the prostate, breast or head and neck.

Surface brachytherapy: This technique involves placing the radioactive source on the surface of the skin or a body organ, such as in skin cancer or eye cancer.

Systemic brachytherapy: This technique involves swallowing or injecting a radioactive substance that travels through the bloodstream to reach cancer cells throughout the body. It is used for certain types of cancer, such as thyroid cancer or bone metastases.

## Benefits of radiation therapy

Radiation therapy can be an effective treatment for many types of cancer, such as:

– Breast cancer

– Prostate cancer

– Lung cancer

– Head and neck cancer

– Skin cancer

– Cervical cancer

– Brain tumors

Some of the benefits of radiation therapy are:

– It can shrink or destroy tumors that are not suitable for surgery or chemotherapy.

– It can kill any remaining cancer cells after surgery or chemotherapy to prevent recurrence or metastasis.

– It can relieve symptoms such as pain, bleeding, pressure or obstruction caused by tumors.

– It can be given as a local treatment that targets a specific part of the body, sparing healthy tissues from unnecessary exposure.

– It can be given in combination with other treatments, such as surgery, chemotherapy, immunotherapy or hormone therapy, to enhance their effectiveness.

According to the American Cancer Society, more than half of people with cancer undergo radiation therapy¹.

## Challenges of radiation therapy

Radiation therapy is not without its challenges and side effects. Some of the challenges of radiation therapy are:

– It requires careful planning and precision to deliver the optimal dose and avoid harming normal tissues.

– It may not work for all types of cancer or for cancers that have spread to multiple sites in the body.

– It may cause short-term or long-term side effects, depending on the dose, duration, location and type of radiation therapy.

– It may interact with other treatments or medications, so it is important to inform your doctor about any other therapies you are receiving or planning to receive.

– It may require frequent visits to the hospital or clinic, which can be inconvenient, costly or stressful.

Some of the common side effects of radiation therapy are:

– Skin changes, such as redness, dryness, itching, peeling or blistering

– Fatigue, weakness or tiredness

– Nausea, vomiting or diarrhea

– Hair loss in the treated area

– Mouth sores, dry mouth or difficulty swallowing (for head and neck cancers)

– Urinary problems, such as burning, frequency or urgency (for pelvic cancers)

– Sexual problems, such as erectile dysfunction or vaginal dryness (for pelvic cancers)

– Infertility or reduced fertility (for pelvic cancers)

– Lymphedema (swelling caused by fluid buildup) in the arms or legs (for breast or pelvic cancers)

– Bone loss or fracture (for bone cancers)

– Secondary cancers (rare but possible)

Most side effects are temporary and improve after treatment is completed. However, some side effects may persist for months or years after treatment. Your doctor will monitor your condition and prescribe medications or supportive care to help you cope with the side effects. You can also take some steps to reduce the impact of side effects, such as:

– Protecting your skin from sun exposure and using gentle moisturizers

– Eating a balanced diet and drinking plenty of fluids

– Getting enough rest and exercise

– Practicing good oral hygiene and avoiding alcohol and tobacco

– Seeking emotional support from family, friends or counselors

## Conclusion

Radiation therapy is a powerful tool in the fight against cancer. It can offer many benefits for people with cancer, such as shrinking tumors, preventing recurrence and relieving symptoms. However, it also poses some challenges and side effects that need to be considered and managed. If you have been diagnosed with cancer and are considering radiation therapy as a treatment option, talk to your doctor about the pros and cons of this therapy for your specific case. Together, you can make an informed decision that suits your needs and preferences.

We hope this blogpost has given you some useful information and awareness about radiation therapy for cancer. If you have any questions or comments, please feel free to contact at #CHECKUP CANCER. Thank you for reading!

## References

(1) Radiation Therapy: Purpose, Risks, Procedure, and More – Healthline. https://www.healthline.com/health/radiation-therapy

(2) Radiation Therapy for Cancer: Types, Uses, Side Effects – Verywell Health. https://www.verywellhealth.com/radiation-therapy-for-cancer-5197127

(3) Radiation therapy | Canadian Cancer Society. https://cancer.ca/en/treatments/treatment-types/radiation-therapy

(4) Advantages and Disadvantages of Radiation Therapy – ZenOnco.io. https://zenonco.io/cancer/advantages-and-disadvantages-of-radiation-therapy/

(5) How Radiation Therapy Is Used to Treat Cancer. https://www.cancer.org/cancer/managing-cancer/treatment-types/radiation/basics.html

(6) Types of radiation therapy: How they work and what to expect. https://www.medicalnewstoday.com/articles/types-of-radiation-therapy

(7) Radiation therapy – Mayo Clinic. https://www.mayoclinic.org/tests-procedures/radiation-therapy/about/pac-20385162

(8) Radiation Therapy for Cancer: How Does It Work? – Cleveland Clinic. https://my.clevelandclinic.org/health/treatments/17637-radiation-therapy