Radiation therapy is a medical treatment used to fight cancer. It uses high doses of radiation to kill cancer cells or slow their growth. Radiation is a type of energy that can come from special machines or radioactive substances. When doctors use radiation therapy, they aim it at the cancer cells in a specific part of the body.
How Does Radiation Therapy Work?
Radiation therapy works by damaging the DNA inside cancer cells. DNA is the part of the cell that controls how it grows and divides. When the DNA is damaged, the cancer cells can't grow or divide properly and eventually die. Radiation can also affect healthy cells, but they can repair themselves better than cancer cells.
There are two main types of radiation therapy:
External Beam Radiation Therapy (EBRT): This is the most common type of radiation therapy, and it's a machine outside the body that directs radiation at the cancer. The machine can move around you to aim the radiation from different angles.
Forms of EBRT:
3D Conformal Radiation Therapy (3D-CRT): uses imaging technology to create a 3D model of the tumor and allows the radiation beams to be shaped to match the tumor's shape, which doesn't affect nearby tissue.
Intensity-Modulated Radiation Therapy (IMRT): is an advanced form of 3D-CRT. It varies the intensity of each radiation beam and allows for more precise targeting of the tumor, which reduces damage to the surrounding healthy tissue.
Image-Guided Radiation Therapy (IGRT): uses imaging during each treatment session and ensures the radiation is accurately targeted by adjusting to the body's movements.
Stereotactic Body Radiation Therapy (SBRT) and Stereotactic Radiosurgery (SRS): deliver very high doses of radiation to small tumors. SBRT is often used for body tumors, while SRS is used for brain tumors.
Proton Beam Therapy: uses protons instead of traditional X-rays and is often used for tumors in sensitive areas, like near the brain or the spinal cord.
Internal Radiation Therapy (Brachytherapy): This involves placing a small amount of radioactive material inside your body, near the cancer. This type of therapy is often used for cancers of the prostate, cervix, or breast.
Forms of Brachytherapy:
Low-Dose Rate (LDR) Brachytherapy: places small radioactive seeds inside or near the tumor that emit radiation over several weeks or months, and are often used for prostate cancer.
High-Dose Rate (HDR) Brachytherapy: places a higher dose of radiation in or near the tumor for a short period. This treatment is repeated over several sessions and the radioactive source is inserted through a catheter and removed after a few minutes. It's commonly used for cervix, breast, or other forms of cancer.
Permanent Brachytherapy: small radioactive seeds that are permanently implanted into the tumor area, these seeds emit radiation over time and eventually become inactive.
Temporary Brachytherapy: radioactive material is temporarily placed in or near the tumor through applicators or catheters. After the prescribed dose is delivered, the material is removed.
Side Effects of Radiation Therapy:
Fatigue:
One of the most common side effects.
Patients often feel tired during and after treatment.
Fatigue can vary in intensity and duration.
Skin Changes:
Skin in the treated area can become red, irritated, or sensitive, similar to a sunburn.
Skin may peel, blister, or become dry and itchy.
Changes usually start a few weeks into treatment and can last for several weeks after.
Hair Loss:
Occurs in the treated area if radiation is aimed at parts of the body with hair.
Hair loss is usually temporary, but in some cases, it can be permanent.
Works Cited
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