Intraoperative radiation therapy may be used to treat the following types of cancers:

• Breast cancer, if the following criteria are met:
• Early-stage breast cancer
• Lymph nodes have tested negative for cancer cells
• Tumor is less than 2.5 cm in diameter
• Above 50 years of age
• Other types of cancers that can be treated using IORT include:
• Bladder cancer
• Prostate cancer
• Colorectal cancer
• Sarcoma (soft tissue cancer)
• Head and neck cancers
• Cervical cancer 
• Endometrial cancer
• Kidney cancer 

1. Physical examination: The doctor will check the symptoms, medical history, and family history of the patient.
2. Imaging tests: CT scans, MRI scans, and ultrasounds are done to obtain clear images of the cancerous organ.
3. Mammography: A mammogram is an x-ray image of the breast. It helps the doctor to look for early signs of breast cancer.
4. Endoscopy: An endoscope (a tube having a camera on one end) is used to examine the cancerous organ internally.
5. Blood tests: Certain medical conditions can be detected using blood tests.
6. Electrocardiogram (ECG): This test helps in obtaining the electrical activity of the heart.
7. Echocardiogram: The internal image of the heart can be obtained using an echocardiogram.
8. Chest x-ray: The condition of the internal organs in the chest region can be evaluated using a chest x-ray.
9. Biopsy: The suspected tissue growth is surgically excised and sent to the laboratory to check for the presence of cancer cells.

The procedure is generally done under general anesthesia, that is, you will be asleep during the procedure.
The surgeon will first make an incision or cut in the surgical area.
Following the surgical removal of the tumor, the radiation oncologist will assess the area to check the likely location of the leftover cancer cells.
The healthy tissues and organs are moved out of the way gently.
IORT can be delivered using x-rays, electron beams, low-energy x-rays, or high-dose-rate brachytherapy.
The applicator of the IORT device, which either used x-rays or electrons, is placed directly into the tumor bed (the opening where the tumor was).
The radiation dose is directly delivered to the tumor bed through the applicator.
Sometimes, you may get IORT using radioactive seeds inside a special type of mesh. This is known as high-dose-rate brachytherapy. The mesh will be cut to fit the treatment area and then sewed into its place by the surgeon.
The radioactive seeds fiber treatment where needed until the radiation runs out. The mesh will stay in the body but will dissolve over time.
The procedure may take approximately half an hour to complete.
The surgeon will then close the incision using sutures (stitches).

Intraoperative radiation therapy may have the following side effects:
Fatigue
Skin irritation
Bruising or bleeding 
Fluid buildup in the breast (if treatment is performed for breast cancer)
Difficulty in swallowing 
Anemia
Constipation
Diarrhea
Dizziness
Headache
Pain
Problems in sleep
Urinary problems
Slow wound healing
Nerve damage

It is normal to have some tenderness and swelling in the treatment area after the procedure.
Side effects like fatigue and skin irritation may be observed a couple of days after treatment.
If you have had brachytherapy, which is a type of internal beam radiation therapy, your body will be emitting radiation after the procedure. It is therefore advisable to not go near other people, especially young children and pregnant women, for a few days after treatment to prevent them from getting exposed to radiation.
You will be explained in detail how to care for your wound area and keep the area clean and dry.
The doctor will determine if additional treatment is needed after IORT to treat cancer.
Follow-ups with the doctor are a must to gauge the success of treatment, check for any recurrence of cancer, and assess the need for additional forms of cancer treatments.