The radiation dose to the skin overlying the thyroid was measured for 91 women undergoing routine mammographic screening. Measurement was made over 6 days using thermoluminescent dosimeter (TLD) detectors taped appropriately to the neck. An average skin dose of 0.39 +/- 0.22 mGy per mammographic examination was measured with measurements ranging from background levels to 1.15 mGy. The average dose was significantly correlated to the milliampere-seconds for a total procedure. The mediolateral-oblique view was found to give a 2.4-fold greater skin dose at the thyroid than the craniocaudal view. After considering depth dose data from the literature it was conservatively estimated that the dose to the thyroid gland might be 10% of the skin dose overlying the thyroid. This corresponds to an average thyroid dose during mammography of approximately 0.04 mGy which is considered insignificant compared with the average breast dose (4 mGy) and in light of the relevant available literature on the risk to the thyroid.

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Aims To demonstrate the magnitude of the potential problem caused by the trend towards using positron emission tomography prostate‐specific membrane antigen scans on men in rural Australia. Context Prostate‐specific membrane antigen positron emission tomography scans have higher sensitivity to detect metastatic prostate cancer than other imaging modalities, especially at lower prostate specific antigen (PSAs). This has led to proposals that prostate‐specific membrane antigen be the gold standard to investigate men with a suspicion of prostate cancer. There is a trial underway in Australia examining the use of positron emission tomography prostate‐specific membrane antigen in pre‐biopsy men. Disparities in access to care and outcomes for prostate cancer for men in rural Australia are well documented. Incorporating positron emission tomography prostate‐specific membrane antigen into the primary diagnostic pathway for prostate cancer creates a risk of further entrenching or worsening this inequity due to the lack of positron emission tomography scanners in rural locations. Approach As a surrogate marker for restricted access, we determined the proportion of men over 50 more than 1.5 hours from a positron emission tomography scanner, with local government areas as the unit of assessment. Conclusion Of the 505 local government areas, 309 were greater than 1.5 hours from the nearest positron emission tomography scanner. Of 3 793 865 men, over 50 585 689 lived in the 309 local government areas with restricted access to a positron emission tomography scanner. Our study highlights the risk of exacerbating inequalities in prostate cancer care experienced by men in rural areas. If positron emission tomography prostate‐specific membrane antigen becomes the new gold standard, one in 6 men will face geographic barriers to access the standard of care. Future considerations of positron emission tomography prostate‐specific membrane antigen must take this into account.