A review of Kilovoltage (kV) Radiotherapy Treatment in the UK: Quality Control, Radiation Dosimetry, Treatment Equipment and Workload.

Abstract

Objectives: To survey kilovoltage (kV) radiotherapy in the UK, updating a 2016 study, focussing on radiotherapy physics, including equipment quality control (QC) and radiation dosimetry, with information on installed equipment and clinical activity.

Methods: All UK radiotherapy physics departments (n = 68) were invited to complete a comprehensive survey. An analysis of the installed equipment base, patient numbers, clinical activity, QC testing and radiation dosimetry processes were undertaken.

Results: 91% of centres (n = 62) responded to the survey. kV radiotherapy was available in 70% of UK radiotherapy departments, with a wide variation in workload; 7 to 436 patients/centre annually. There has been an increase in the centres using treatment calculation software rather than manual methods, up from 36% in 2016 to 50% in the current study. Only 50% of centres use a calculation check method different to the primary method. There was also an increase in use of the addendum to the UK dosimetry code of practice, enabling medium energy calibration in-air rather than at depth in phantom, citing "clinical relevance". Appropriate levels of quality control testing were being conducted at UK centres, with IPEM Report 81 cited as a primary source of guidance. Good consensus for the frequency and tolerance values used for QC was seen across UK centres.

Conclusions: A comprehensive review of consensus practice for quality control and dosimetry in kV radiotherapy across the UK is presented, with supporting information on equipment installation and clinical use.

Advances in knowledge: Updated data is presented on kV radiotherapy treatment in the UK, with focus on physics aspects of QC and dosimetry.