Radioimmunotherapy uses a form of radiation therapy combined with monoclonal antibody therapy to fight lymphoma.
Rather than using ‘external beam’ radiation therapy that is generated in a high-power X-ray machine (see ‘Radiation Therapy’), radioimmunotherapy uses a radioactive element (radioisotope) such as iodine-131, that emits radiation and is capable of killing cancer cells.
The radiolabelled-antibody attaches onto the cancerous B-cells so that the radiation is delivered specifically to lymphoma cells (see the previous section on Monoclonal Antibody Therapy for a more detailed explanation of how this works).
Once attached, the radiation kills the cancerous B-cell as well as any other lymphoma cells that are nearby.
The therapy regime typically consists of the following:
- An infusion of non-radioactive antibody, followed on the same day by an injection of a small amount of radioactive antibody, immediately followed by a scan under a CT/SPECT gamma camera.
- Three or four days later another scan is performed.
- One week after the initial infusion, another infusion of antibody is given, followed by another scan. The three scans are then compared and used for dosimetry to determine the correct radioactive therapy activity to be prescribed. The radioactive antibody is then given, also by intravenous infusion.
With radioimmunotherapy, the patient becomes mildly radioactive (which decreases over a period of a few weeks) and needs to take some precautions to minimise radiation exposure to other people. Depending on the relevant laws in the state where the therapy is conducted, patients may be required to either stay in hospital for several days or remain confined at home for up to one week.
Side effects of radioimmunotherapy may include a mild allergic-type reaction to the antibody, mild nausea that may last for one or two days, and some tiredness or lethargy for a few days after therapy. Hair loss, radiation burns, infertility and other side effects do not occur.
This form of treatment is available in only a few hospitals in Australia, including the Peter Mac Cancer Hospital in Melbourne, and Fremantle Hospital in Western Australia.
From The DVD - "Your Journey Of Lymphoma Treatments"
Related video : Chapter 11 - What Is Radioimmunotherapy