Medicine radiotherapy

The decision to undertake Y microembolization should be made following the consent of an interdisciplinary team from interventional radiology, nuclear medicine, radiotherapy, medical and surgical oncology, and transplantation medicine, since a wide variety of conditions and parameters have to be considered (Table 2.7.3). 

Class 7 Radioactive substances and articles (sources In nuclear Industry, Industrial radiography, military, nuclear medicine, radiotherapy)... 

An alternative anti-cancer strategy entails insertion of a copy of a tumour suppresser gene into cancer cells. For example, a dehciency in one such gene product, p53, has been directly implicated in the development of various human cancers. It has been shown in vitro that insertion of a p53 gene in some p53-dehcient tumour cell lines induces the death of such cells. A potential weakness of such an approach, however, is that 100 per cent of the transformed cells would have to be successfully treated to fully cure the cancer. Tumour suppressor-based gene therapy in combination with conventional approaches (chemotherapy or radiotherapy) may, therefore, prove most efficacious, and the sole gene-therapy-based medicine approved to date (in China only) is based upon this approach (Box 14.2). 

In view of this, and in view of ARL s experience over the years, there were only two results of significant concern, and these have been adequately addressed (a single capsule receiving only half the required dose, and a 15.4% deviation due to a misunderstanding. Some Australian radiotherapy centres have not yet adopted the IAEA dosimetry protocol TRS 277. This protocol has been recommended by the Australian College of Physical Scientists and Engineers in Medicine, and calibration factors supplied by ARL are appropriate for the use of this protocol. ARL strongly recommends the use of TRS 277 in a water phantom by all radiotherapy centres in Australia (Huntley and Nette, 1993). 

In general, p - and p" -Particles penetrate deep into the medium however, they do not cause damage to tissues and organs. Radionuclides that decay by p-Particle emissions are used very extensively in nuclear medicine for diagnostic and therapeutic applications. Positron-emitting nuclides are used in nuclear medicine for diagnostic purposes. p+-Emitting radionuclides are under active study for use in radiotherapy. An example... 

Californium-252 is also used in medicine. When injected into the body, it tends to be deposited in bones. The radiation it gives off can be used to determine the health of the bone. Californium-252 is also used to treat ovarian and cervical cancer. Some experts see a number of important medical uses for californium-252 in the future, especially in radiotherapy (medical treatment using radiation). 

Falk SA. Thyroid disease Endocrinology, surgery, nuclear medicine, and radiotherapy. 2nd ed. Philadelphia Lippincott-Raven Publishers, 1997. 

Cobalt-60 was a common isotope for external radiotherapy, but it has mostly been replaced by linear accelerators that provide high-energy electrons (P particles) without a dangerous isotope source. It is still used for food irradiation. Iodine-131 is used to combat diseases of the thyroid and of several types of cancer. A list of isotopes used in nuclear medicine may be found at http //www.cbvcp.com/nmrc/mia.html. 

For therapy radiographers, supply and administration of medicines is not limited to the adverse consequences of radiotherapy. These radiographers have a significant involvement in the production of images that inform radiotherapy planning and a growing number... 

Since the late 1990s, therapy radiographers have been trained to administer medicines for the management of radiotherapy side effects, such as pain rectal symptoms, constipation, diarrhoea skin reactions, wound care oral care nausea and vomiting. They are also beginning to use PGDs for X-ray contrast agents. 

Study and classification of serotonin receptors has resulted in the design and synthesis of highly selective medicines such as Sumatriptan, for the treatment of migraine, Ondansetron for the suppression of the nausea and vomiting caused by cancer chemotherapy and radiotherapy, and Alosetron for treatment of irritable bowel syndrome. 

Bonner J et al. Radiotherapy plus cetuximab for squamous-cell carcinoma of the head and neck. The New England Journal of Medicine 2006 354 567-578. 

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