Cohort profile: radiotherapy dataset (RTDS) in England.

PURPOSE: The purpose of the Radiotherapy Dataset (RTDS) is to collect consistent and comparable data across all providers of National Health Service (NHS)-funded radiotherapy and to provide intelligence for service planning, commissioning, clinical practice and research. PARTICIPANTS: The RTDS is a mandated dataset requiring providers to collect and submit data monthly for patients treated in England. Data is available from 01 April 2009 to 2 months behind the calendar month.The National Disease Registration Service (NDRS) started receiving data from 01 April 2016. Prior to this, the National Clinical Analysis and Specialised Applications Team (NATCANSAT) were responsible for the RTDS. NDRS holds a copy of the NATCANSAT data for English NHS providers.The RTDS contains clinical information on the primary disease being treated, modality and intent of treatment, dose fractionation and hospital appointment details. Due to constraints in RTDS coding, linkage to the English National Cancer Registration dataset is beneficial. FINDINGS TO DATE: The RTDS has been linked to the English National Cancer Registration and Systemic Anti-Cancer Therapy (SACT) datasets and to Hospital Episode Statistics (HES) to provide a more complete picture of the patient cancer pathway. Findings include a study to compare outcomes for patients treated with radical radiotherapy, an investigation of factors influencing 30-day mortality, assessing sociodemographic variation in the use of treatment and a study to assess the service impact of the COVID-19 pandemic. A range of other studies have been completed or are ongoing currently. FUTURE PLANS: The RTDS can be used for a variety of functions including cancer epidemiological studies to investigate inequalities in treatment access; provide service planning intelligence; monitor clinical practice; and support clinical trial design and recruitment. Collection is to continue indefinitely, with regular updates to the data specification to enable capture of more detailed information on radiotherapy planning and delivery.

Radiation exposures in pregnancy, health effects and risks to the embryo/foetus-information to inform the medical management of the pregnant patient.

Generally, intentional exposure of pregnant women is avoided as far as possible in both medical and occupational situations. This paper aims to summarise available information on sources of radiation exposure of the embryo/foetus primarily in medical settings. Accidental and unintended exposure is also considered. Knowledge on the effects of radiation exposure on the developing embryo/foetus remains incomplete-drawn largely from animal studies and two human cohorts but a summary is provided in relation to the key health endpoints of concern, severe foetal malformations/death, future cancer risk, and future impact on cognitive function. Both the specific education and training and also the literature regarding medical management of pregnant females is in general sparse, and consequently the justification and optimisation approaches may need to be considered on a case by case basis. In collating and reviewing this information, several suggestions for future basic science research, education and training, and radiation protection practice are identified.

IPEM topical report: the first UK survey of dose indices from radiotherapy treatment planning computed tomography scans for adult patients.

CT scans are an integral component of modern radiotherapy treatments, enabling the accurate localisation of the treatment target and organs-at-risk, and providing the tissue density information required for the calculation of dose in the treatment planning system. For these reasons, it is important to ensure exposures are optimised to give the required clinical image quality with doses that are as low as reasonably achievable. However, there is little guidance in the literature on dose levels in radiotherapy CT imaging either within the UK or internationally. This IPEM topical report presents the results of the first UK wide survey of dose indices in radiotherapy CT planning scans. Patient dose indices were collected for prostate, gynaecological, breast, lung 3D, lung 4D, brain and head and neck scans. Median values per scanner and examination type were calculated and national dose reference levels and 'achievable levels' of CT dose index (CTDIvol), dose-length-product (DLP) and scan length are proposed based on the third quartile and median values of these distributions, respectively. A total of 68 radiotherapy CT scanners were included in this audit. The proposed dose reference levels for CTDIvol and DLP are; prostate 16 mGy and 570 mGy · cm, gynaecological 16 mGy and 610 mGy · cm, breast 10 mGy and 390 mGy · cm, lung 3D 14 mGy and 550 mGy · cm, lung 4D 63 mGy and 1750 mGy · cm, brain 50 mGy and 1500 mGy · cm and head and neck 49 mGy and 2150 mGy · cm. Significant variations in dose indices were noted, with head and neck and lung 4D yielding a factor of eighteen difference between the lowest and highest dose scanners. There was also evidence of some clustering in the data by scanner manufacturer, which may be indicative of a lack of local optimisation of individual systems to the clinical task. It is anticipated that providing this data to the UK and wider radiotherapy community will aid the optimisation of treatment planning CT scan protocols.