Experience of pain during mammographic screening by three different compression paddles.

INTRODUCTION: Experience of pain during screening mammography is shown to affect further attendance negatively. We aimed to explore the experience of pain during screening mammography using three different breast compression paddles. METHODS: Using a self-report questionnaire, we collected information on pain experienced during mammography from 938 women screened in Bodø at Nordland Hospital County in 2018, as a part of BreastScreen Norway. Pain was assessed by a numeric rating scale (NRS, 0-10). A fixed paddle, a flexible paddle or a fixed paddle standardizing pressure (study paddle) were used during screening. Compression force (kg) was recorded by the radiographers for each screening examination. Log-binomial regression was used to determine the relative risk (RR) of severe (≥7 on NRS) versus mild/moderate (<7 on NRS) experience of pain associated with type of compression paddle, adjusting for breast tenderness, shoulder(s) and/or neck pain prior to screening, compression force, age, body mass index and screening history. RESULTS: Mean score of self-reported experienced pain was 2.8 for the fixed, 2.3 for the flexible and 2.8 for the study paddle (p < 0.03 for fixed versus flexible and for flexible versus study paddle). Adjusted RR of severe pain was higher for the fixed (RRAdj 2.01, 95%CI 1.13-3.59) and the study paddle (RRAdj 2.52, 95%CI 1.44-4.42) compared to the flexible paddle. Breast tenderness was associated with a higher risk (RRAdj 1.93, 95%CI 1.04-3.58) of severe pain compared to no breast tenderness. CONCLUSION: Women screened with the flexible paddle reported lower experience of pain than those screened with the fixed or study paddle. IMPLICATION FOR PRACTICE: The flexible compression paddle might be the best choice regarding experience of pain in screening mammography. Breast tenderness should be considered by the radiographers in a practical screening setting.

Standardised or individualised X-ray tube angle for mediolateral oblique projection in digital mammography?

INTRODUCTION: We aimed to investigate whether there were any differences in positioning criteria related to the presentation of the pectoralis major muscle (pectoral muscle) for women of different heights using a standardized 60° X-ray tube angle for mammograms in mediolateral oblique (MLO) projection. METHODS: Data from MLO mammograms of right breasts of 45,193 women screened in BreastScreen Norway 2016-2019 were used. The positioning criteria were related to the pectoral muscle length (measure A and measure B), width and shape and considered adequate or inadequate depending on the degree of fulfilling the criteria. Data associated with the pectoral muscle were extracted from Volpara, an automated software for breast density assessment. Information on height was obtained from a self-reported questionnaire received by the women together with the invitation to attend the screening program. Women were divided into three groups based on the height percentiles (P) in the Norwegian growth curves: < 25th percentile (75th percentile (>P75th: >170 cm). Logistic regression was used to analyse the odds of adequate pectoral muscle length A and B, and shape, adjusting each model for screening technique and equipment model. Results were presented with odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Mean age of the screened women was 61.5 (SD = 4.8) years. The adequate measure for the pectoral muscle length A was obtained for 25.9% (11,724/45,193), length B for 76.3% (34,489/45,193), width for 75.0% (33,894/45,193) and shape for 97.6% (44,118/45,193) of the mammograms. Adjusted odds of an adequate pectoral muscle length A were lower for women of P75th (OR = 1.08, 95% CI 1.02-1.14) compared to women of P25-75. Odds of an adequate pectoral muscle shape were higher for women of P75th (OR = 0.92, 95% CI 0.87-0.97) compared to women of P25-75th. CONCLUSION: The 60° X-ray tube angle might suit most of the female population offered mammographic screening in Norway, but women of a relatively low height (163 cm or lower) might benefit from an X-ray tube angle less than 60-degrees. IMPLICATIONS FOR PRACTICE: Using 60° X-ray tube angle for the MLO mammograms in BreastScreen Norway fit the majority of the participating women. More research is needed to change the protocol associated with the tube angle for women shorter than 163 cm.

Mammographic features and screening outcome in a randomized controlled trial comparing digital breast tomosynthesis and digital mammography.

PURPOSE: To compare the distribution of mammographic features among women recalled for further assessment after screening with digital breast tomosynthesis (DBT) versus digital mammography (DM), and to assess associations between features and final outcome of the screening, including immunohistochemical subtypes of the tumour. METHODS: This randomized controlled trial was performed in Bergen, Norway, and included 28,749 women, of which 1015 were recalled due to mammographic findings. Mammographic features were classified according to a modified BI-RADS-scale. The distribution were compared using 95 % confidence intervals (CI). RESULTS: Asymmetry was the most common feature of all recalls, 24.3 % (108/444) for DBT and 38.9 % (222/571) for DM. Spiculated mass was most common for breast cancer after screening with DBT (36.8 %, 35/95, 95 %CI: 27.2-47.4) while calcifications (23.0 %, 20/87, 95 %CI: 14.6-33.2) was the most frequent after DM. Among women screened with DBT, 0.13 % (95 %CI: 0.08-0.21) had benign outcome after recall due to indistinct mass while the percentage was 0.28 % (95 %CI: 0.20-0.38) for DM. The distributions were 0.70 % (95 %CI: 0.57-0.85) versus 1.46 % (95 %CI: 1.27-1.67) for asymmetry and 0.24 % (95 %CI: 0.16-0.33) versus 0.54 % (95 %CI: 0.43-0.68) for obscured mass, among women screened with DBT versus DM, respectively. Spiculated mass was the most common feature among women diagnosed with non-luminal A-like cancer after DBT and after DM. CONCLUSIONS: Spiculated mass was the dominant feature for breast cancer among women screened with DBT while calcifications was the most frequent feature for DM. Further studies exploring the clinical relevance of mammographic features visible particularly on DBT are warranted.