External beam radiotherapy (EBRT) is delivered by directing the radiation at the tumour from outside the body. Types of external beam radiotherapy include conventional EBRT, intensity modulated radiation therapy (IMRT) and 3-dimensional conformal radiotherapy (3D-CRT).

Brachytherapy is delivered by placing the radiation source in close proximity to the tumour site. The radioactive isotopes are sealed in tiny pellets or “seeds” which are placed in the body using delivery devices such as needles or catheters. Types include interstitial brachytherapy, which uses a source placed within tumour tissue, for example, within a prostate tumour; and intracavitary brachytherapy, whereby the source is placed within a surgical cavity or a body cavity. Brachytherapy can involve the temporary or permanent placement of radioactive sources.

Unsealed radioisotopes or systemic radioisotope therapy is delivered by infusion into the bloodstream or by ingestion and is a form of targeted therapy. Targeting can be due to the chemical properties of the isotope, for example, radioiodine is specifically absorbed by the thyroid gland. It can also be achieved by attaching the radioisotope to another molecule or antibody to guide it to the target tissue. Examples of treatment with unsealed radioisotopes include the infusion of metaiodobenzylguanidine (MIBG) to treat neuroblastoma and of oral iodine-131 to treat thyroid cancer.

Radiotherapy treatment type is collected for all courses of radiotherapy delivered to the patient during the course of treatment.

The radiotherapy treatment type is recorded regardless of whether the course of treatment is completed as intended, and regardless of the intent or timing of treatment.

More than one radiotherapy treatment type may be administered during the course of treatment; select the appropriate code value.

If external beam radiotherapy and/or brachytherapy were administered, the radiation dose received and number of fractions should also be collected as well as the start and finish dates of the radiotherapy.

Most external beam radiotherapy is delivered on an outpatient basis.

The radiotherapy treatment modality will typically be found in the radiation oncologist's summary letter for the course of treatment or in the radiotherapy treatment summary in the patient's medical record.

Commission on Cancer, American College of Surgeons

New South Wales Health Department

American College of Surgeons 2002. Facility Oncology Registry Data Standards (FORDS), 2009 revision. Commission on Cancer

American College of Surgeons 1998. Standards of the Commission on Cancer: Registry Operations and Data Standards (ROADS), Volume II. Commission on Cancer

Cancer Institute NSW 2006. NSW Clinical Cancer Registration: Minimum Data Set Data Dictionary, version 1.9 draft