2/14/2015
Medical Isotopes: Frequently Asked Questions
What is a medical isotope? A medical isotope is a very small quantity of radioactive substance used in safe, cost effective imaging and treatment of disease. New technologies enable medical isotopes to be delivered directly to the site of diseased cells. This is different from external beam radiation treatment where radiation is directed from outside of the body. Who uses medical isotopes? The medical specialty that utilizes medical isotopes for diagnosis and treatment is called nuclear medicine. The doctors that perform nuclear medicine procedures for cancer are called radiation oncologists. What can medical isotopes do in diagnosis? Radioisotopes give off energy that can be detected by special equipment. When small quantities are introduced into the body, the imaging equipment tracks their location and movement. This enables the doctors to learn more about the diseased tissues than a diagnostic procedure that just takes a picture from the outside. Medical isotope diagnostic procedures often facilitate an earlier and more complete disease diagnosis and therefore more rapid and effective treatment. What can medical isotopes do in cancer treatment? The energy given off by radioisotopes is very effective at zapping diseased cells. When they are delivered straight to the cancer cells, healthy tissues are spared while cancer cells are eliminated. Medical isotopes are delivered to the cancer cells in several different ways. What different types of medical isotope treatments are there? Brachytherapy is a form of cancer treatment where tiny "seeds" containing medical isotopes are accurately placed within and near a tumor. Brachytherapy is FDA approved and used for localized prostate cancer, liver cancer, head and neck cancers, gynecological cancers and others. Radioimmunotherapy is a type of treatment where doctors inject antibodies that have isotopes attached like little backpacks. The antibodies (called monoclonal antibodies) then flow through the bloodstream and attach themselves to the cancerous cells. The energy from the medical isotopes is thus targeted straight to the cancer. This type of treatment is showing great promise for blood cancers such as leukemia, lymphoma, and multiple myeloma. Most Radioimmunotherapy treatments are still in clinical trials. Medical isotopes can also be directed to cancerous cells by a carrier that has an attraction to a certain part of the body. Chemical phosphonates can be paired with medical isotopes and sent to the bone, since phosphonate is a natural building block of bone matrix. FDA approved treatments for pain associated with cancer that has spread to the bone are based on this delivery system. The medical isotope Iodine http://www.medicalisotopes.org/faq.html
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