Characterisation of Portuguese radiotherapy departments: Organisation, occupational exposure values and diagnostic reference levels for breast and prostate computed tomography planning

R Guisantes; J Santos; A J Ferreira

doi:10.1016/j.radi.2024.04.007

Characterisation of Portuguese radiotherapy departments: Organisation, occupational exposure values and diagnostic reference levels for breast and prostate computed tomography planning

Radiography (Lond). 2024 Apr 23;30(3):932-937. doi: 10.1016/j.radi.2024.04.007. Online ahead of print.

Authors

R Guisantes¹, J Santos², A J Ferreira³

Affiliations

¹ Unidade Local de Saúde de Coimbra, Radiotherapy Department, Praceta Mota Pinto, 3000-075, Coimbra, Portugal. Electronic address: rafaelaguisantes@ulscoimbra.min-saude.pt.
² Instituto Politécnico de Coimbra, ESTESC - Coimbra Health School, Medical Imaging and Radiotherapy, Rua 5 de Outubro, S. Martinho do Bispo, 3046-854, Coimbra, Portugal. Electronic address: joanasantos@estesc.ipc.pt.
³ Faculty of Medicine, University of Coimbra, Portugal. Electronic address: aferreira@fmed.uc.pt.

PMID: 38657386
DOI: 10.1016/j.radi.2024.04.007

Abstract

Introduction: Portugal currently hosts 24 active radiotherapy departments, 8 public and 16 privates, presenting potential radiation exposure risks to multidisciplinary teams. Patients in these treatments also face ionising radiation during treatment planning and verification.

Methods: Authorisation and ethical approval were secured for a national online survey, disseminated to radiotherapy departments across Portugal. The survey encompassed three sections: equipment, staff, and radiographer role characterisation; occupational exposure values for one month; and exposure parameters, including computed tomography (CT) dose values [CT dose index (CTDI_vol) and dose length product (DLP)] for breast and prostate cancer CT planning. Local Diagnostic Reference Levels (DRLs) derived were based on the 75th percentile of median dose values.

Results: The study garnered a 50% response rate from public institutions, 12,5% from private and 25% from all active radiotherapy institutions in Portugal. All departments employ Three-Dimensional Conformal Radiation Therapy (3D-CRT) and incorporate Intensity Modulated Radiation Therapy (IMRT) and/or Volumetric Modulated Arc Therapy (VMAT) irradiation techniques. Additionally, half of the departments also perform Brachytherapy (BT). Radiographers demonstrated an occupational dose of zero mSv. CT planning dose values were 13 mGy and 512 mGy cm for breast CT and 16 mGy and 689 mGy cm for prostate CT, pertaining to CTDI_vol and DLP, respectively.

Conclusion: Most aspects of national radiotherapy characterisation align with the established literature. Occupational exposure values exhibited consistency across radiotherapy modalities. An approach to national DRLs was formulated for breast and prostate CT planning, yielding values congruent with recent European studies.

Implications for practice: This study offers vital insights for analysing occupational contexts and risk prevention, serving as the initial characterisation of the national radiotherapy landscape. It also pioneers the calculation of DRLs for CT planning in radiotherapy to optimise procedures.

Keywords: Diagnostic reference levels; Occupational exposure; Radiographers; Radiotherapy departments.