An Analysis of Acquisition Dose in Male Mammography

Although primarily used for female patients, mammography is a valuable tool for detecting male breast abnormalities, providing detailed images of breast tissue. Due to the low incidence of male breast imaging, limited male-specific studies exist on radiation exposure. This study measured the acquisition radiation dose of male patients undergoing full-field digital mammography (FFDM) and digital breast tomosynthesis (DBT) at an Australian tertiary hospital and compared these values with published cohorts. The goal was to determine whether differences in breast anatomy between sexes influenced radiation dose levels.

A retrospective analysis of 266 male breast imaging acquisitions (66 patients, 78 procedures) across two hospital sites between February 2019 and April 2024 was performed. Both FFDM (n = 164) and DBT (n = 102) were assessed. Radiation dose metrics, including entrance surface air kerma (ESAK) and glandular dose (GD), were extracted from DICOM headers using a Python script. Data was anonymised and analysed with descriptive statistics, Shapiro-Wilk, Mann-Whitney U, and Pearson correlation to compare modalities and explore associations between patient and technical factors.

Median participant age was 65 years; median breast thickness 51 mm. Median FFDM variables: 28 kVp, 128 mAs, 570 ms exposure time, 2.7 mGy ESAK, 0.83 mGy GD. For DBT: 29 kVp, 100 mAs, 975 ms exposure time, 4.7 mGy ESAK, 1.34 mGy GD. Shapiro-Wilk (p < 0.001) confirmed non-normal distributions. DBT doses were significantly higher than FFDM (Mann-Whitney U, p < 0.001). FFDM GD values were lower than both male and female cohorts reported previously. Breast thickness correlated strongly with FFDM ESAK (Pearson r = 0.72, p < 0.001).

This study quantified ESAK and GD in male FFDM and DBT patients and compared these values with published female cohorts. Male doses were consistently lower, likely from reduced breast thickness and density. This study successfully measured acquisition dose in male mammography patients, identifying differences by sex and highlighting breast anatomy's influence.