Intraoperative Radiation Treatment

Intraoperative radiation therapy (IORT) involves a single-dose radiation treatment which is delivered during breast conserving surgery directly to the tumour site. The radiation treatment takes between 20 and 40 minutes and eliminates the need for any further radiation treatment. The aim of the treatment is to kill any remaining cancer cells at the tumour site.

The standard radiation treatment for breast cancer involves  External Beam Radiation Therapy or “EBRT”. This involves beams of radiation being directed to the patient  using a machine called a linear accelerator.  EBRT is delivered to the whole breast and is delivered daily (week days) over 15 – 30 days, depending on the treatment. This contrasts with treatment delivery using IORT, which requires only a single treatment.

Only certain women will be eligible for intraoperative radiation therapy treatment. Those who have early-stage breast cancer, have negative lymph nodes and are 50 and older may be candidates for Intrabeam.

Watch a video about IORT here.

BCAC has requested that the Ministry of Health promote the immediate introduction into the public health system of intraoperative radiotherapy (IORT) using Intrabeam as a radiation therapy option for selected breast cancer patients. Read our letter to the Minister of Health.

Find out more about the key differences between standard external beam radiation therapy and intraoperative radiaton therapy below.

  • The amount of the breast that is treated with radiation therapy

With external beam radiation therapy, usually the whole breast is treated with radiation therapy.

With intraoperative radiation therapy, just the area where the tumour was located is treated with radiation therapy. This minimises the amount of the healthy organs and tissue that is treated with the radiation therapy.

Undesirable irradiation of healthy tissue: Under EBRT, the radiation beams are external, i.e. come from outside the patient. This means that the radiation must pass through other healthy parts of the patient’s body to hit the intended target. To reach the target, the radiation beam must pass through the healthy tissue (skin, breast, muscle, ribs and organs such as the lung and also the heart if the cancer is on the left side).

With IORT however, the radiation treatment comes from the small probe placed directly within the tumour cavity – i.e. internally from within the patient. Because the probe is placed directly into the cavity where the tumour was removed the radiation used by the IORT probe does not have to first pass through a lot of other healthy tissue to reach its target. This means that the irradiation of some healthy parts of the body is avoided.

Why is this important? With EBRT the unavoidable irradiation to other parts of the body can potentially cause side effects for the patient including inflammation of the lung and heart problems.

  • The duration of the treatment

There is a significant reduction in the treatment time with intraoperative radiation therapy.  Treatment is delivered as a single dose over approximately 25 to 40 minutes while the woman is under anaesthetic.
By contrast, external beam radiation therapy is given each day, Monday to Friday with the weekends off over 3 to 6 weeks, (so a total of 15 to 30 treatments).  The patient is usually in the radiation department for 20 to 30 minutes a day.

Why is this important?  The 15 – 30 daily treatments required with EBRT create a massive disruption to the patient’s quality of life – both psychologically and economically - at a time when the patient is already under significant stress resulting from the diagnosis of cancer and the subsequent cancer surgery.  Depending on the specific circumstances of the individual patient, arrangements must be made for time off work for a period of between three to six weeks, childcare may need to be arranged, regular transport organised over the period to attend treatment, a support person arranged and so on.  These difficulties are further compounded if the patient lives out of town – in such cases accommodation may also  need to be arranged for the duration of the treatment.

  • The timing of the delivery of the radiation therapy

The intraoperative radiation therapy is given as a part of the breast cancer surgery. By comparison, the earliest the external beam radiation therapy is given is approximately 4 to 5 weeks after surgery to allow time for the surgical wound to heal.

What if the cancer comes back after surgery and tradition therapy?

If you have had intraoperative radiation therapy and the cancer does come back in the breast, the cancer can be removed and external beam radiation therapy can be given to the breast, so you can still keep your breast.

If you have had external beam radiation therapy and the cancer comes back the standard treatment is a mastectomy.

Read BCAC's letters to the National Health Committee (2013) and the Minister of Health (2016) requesting intraoperative radiation therapy be introduced into the public health system.