IAEA Laboratories Expand Radiation Medicine Services to High Dose Rate Brachytherapy

A form of radiotherapy, brachytherapy is the application of an encapsulated radioactive source directly into or near a tumour in a human body. Once in place, the source emits ionizing radiation to the surrounding cells or tissue, which damages DNA and inhibits cancer cell growth or kills cancer cells completely.

Brachytherapy treatment can be administered in several ways, depending on the intensity of radiation. In LDR brachytherapy, a low intensity of radiation is used, thereby requiring a patient staying in a hospital for potentially up to seven days. HDR brachytherapy delivers the dose of radiation to the tumour in a few minutes, requiring only a few short treatment sessions to be effective. The treatment is typically delivered on an outpatient basis. The nature of this treatment means HDR brachytherapy uses more practical procedures, provides increased opportunities to optimize the absorbed dose and enhanced radiation protection of staff with shorter treatments requiring reduced exposure to the radiation source.

The type of source used and the method of its delivery depend on the nature and location of the tumour, to be treated.

The new HDR System will be utilised for several new activities in support of Member States. The main service provided will be the calibration of well type chambers used for dosimetry of HDR brachytherapy for Secondary Standards Dosimetry Laboratories (SSDLs) within Member States, who will in turn provide calibration for hospitals. These services, to be provided for both Iridium-192 and Cobalt-60 sources, will help to assure proper source calibration, thereby preventing a patient from receiving too much radiation, which can damage normal tissue, or too little radiation, which may not fully treat a tumour.

"Very few dosimetry standards laboratories currently offer the calibration of well type chambers for HDR brachytherapy," explained Izewska. "We hope to address this challenge over time through the IAEA/WHO Network of SSDLs through which these standards can be more easily disseminated."

In addition to calibration, the Seibersdorf-based laboratory will also be providing training for SSDL staff on the calibration practices and procedures to be followed throughout the calibration process.

*The ReNuAL Project is a three year project to modernize the eight IAEA Nuclear Sciences and Applications Laboratories in Seibersdorf. These labs deliver technical assistance to Member States in the areas of food and agriculture, human health, the environment and the development and use of advanced scientific instruments. With the construction of new laboratory buildings, the acquisition of new equipment and the development of site infrastructure the IAEA aims to establish fit-for-purpose laboratories that will be positioned to more efficiently respond to Member State needs for the next 15-20 years.