Internal Beam Radiation Therapy

The following diagnostic tests could be performed before an internal beam radiation therapy procedure:

1. Physical examination: The doctor checks the physical health, symptoms, and medical history of the patient.
2. Imaging tests: Imaging tests such as CT scans, MRI scans, and ultrasounds may be done to get clear images of the cancerous organ and allow the doctor to plan how much radiation the patient needs and where to place the radioactive source or implant. The scan may be performed after the patient has a radioactive tablet or liquid to highlight the area that may need treatment.
3. Endoscopy: A tube having a camera on one end, known as an endoscope, is used to check the suspected cancerous organ internally.
4. Blood tests: Certain medical conditions can be diagnosed using blood tests.
5. Biopsy: The suspected tissue growth is surgically excised and sent to the laboratory to check for the presence of cancer cells and the type of cancer cells that may be present.

Depending on the type of procedure being performed, internal beam radiation therapy can be done in the following ways:

1. Radioactive liquid treatment:
The patient may be given radioactive liquid treatment in the form of a capsule, drink, or injection.
The different types of radioactive liquids used may include iodine-131, radium-223, phosphorus-32, or strontium-89.
The radioactive portion of the liquid is known as an isotope. It could be attached to another substance, which is designed in a manner to take the isotope into the tumor.
The radioactive liquid will travel through the body, but it mainly collects in the areas where the cancer is located, causing minimal damage to the surrounding healthy cells of the body.

2. Brachytherapy:
Most brachytherapy implants are placed in the body using a catheter (a small, stretchy tube). Sometimes, brachytherapy implants may be placed in the body through a larger device, called an applicator. The catheter or applicator is placed into the body before starting the treatment.
Once the catheter or applicator is in its place, the radiation source is later placed inside it. The radiation source must be kept in its place for a few minutes for several days, or for the remaining life of the patient depending on the type of radiation source used, location of cancer, type of cancer present, the condition of the patient, and other forms of cancer treatments that the patient has undergone.
The different techniques used for brachytherapy are:
Interstitial brachytherapy: This technique involves the placement of the radiation source within the tumor, like within the prostate or breast.
Intracavitary brachytherapy: This technique involves the placement of the radiation source within a body cavity or a cavity created by surgery, like a vagina or windpipe.
Episcleral brachytherapy: This technique involves the attachment of the radiation source to the eye and is used to treat melanoma of the eye.

Internal beam radiation therapy may have the following side effects:
Fatigue
Hair loss
Urinary incontinence (involuntary urine leakage)
Difficulty in urinating
Cough
Erectile dysfunction
Bowel incontinence (involuntary stool passage)
Dyspnea (shortness of breath)
Constipation
Diarrhea
Mouth ulcers
Headaches
Nausea
Vomiting

The radiation source in the body may give off radiation for some time after internal beam radiation therapy. You will therefore need to take certain safety measures after internal radiation therapy like: 
Stay in the private hospital room and protect other people from radiation coming from your body.
Hospital visits by visitors are to be avoided completed or done only at a safe distance after wearing protective gear.
Avoid any contact with young children or pregnant women.
The catheter is removed after treatment completion using LDR or HDR implants.
The doctor prescribes pain-relieving medications before catheter or applicator removal.
It is normal to have tenderness in the catheter or applicator placement area for a few months.
After the removal of the catheter or applicator there is no radiation left in your body and it is safe for you to be around other people.
After the removal of the catheter, you may need to limit your daily activities for one or two weeks.
Follow-up visits and scans are advised by the doctor to check how successful was the treatment.