Objective To carry out the quality control testing and evaluation for three digital mammography systems.Methods The performance of three digital mammography systems was assessed by applying methods recommended in the European guidelines for quality assurance in breast cancer screening and diagnosis and Chinese specification for testing of quality control in X-ray mammography.The performance of X-ray generator of three digital mammography systems were tested and evaluated.CDMAM 3.4 phantom with four different thickness(30,40,50,60 mm) were exposured in DR,PCM,and CR system,respectively.The average glandular dose (AGD) value was measured and image quality figure (IQF) analysis was performed in each thickness.Results The X-ray machine performance of DR and CR was in accordance with existing standard,however the standard was inappropriate to evaluate part of X-ray machine performance of PCM system.The AGDs for system DR were 1.20,1.42,1.75 and 2.20 mGy for 30,40,50 and 60 mm PMMA thickness,respectively.The respective AGDs for system PCM and CR were 0.82,1.19,1.33,1.70 mGy and 0.59,0.88,1.47,2.19 mGy.For the same phantom thickness sequence,the IQFs were 21.36,21.57,27.25 and 30.58 for system DR,28.02,29.10,35.90,and 41.24 for system PCM,whereas they were 39.78,39.30,43.85 and 48.08 for system CR.Conclusions The AGDs of all three systems were in accordance with the values recommended in European guideline.The AGD and IQF could provide an effective way for performance assessment and constancy checks for digital mammography systems.

Objective:Based on the data of Global Burden of Disease 2019 data, to analyze the past, current, and future burden of disability-adjusted life years (DALYs) in China and compare with the international status.Methods:The total number of DALYs, age-standardized DALY rate, and the composition of different subgroups were extracted and described to analyze the time trend in 2000-2019 and the current situation in 2019 for Chinese female breast cancer. The burden of DALYs in 2050 was predicted by Joinpoint using average annual percent change (AAPC).Results:In 2000-2019, the ranking of DALYs caused by female breast cancer in China rose from the fourth to the second in all female cancers. The total DALYs increased by 48.4%, of which the years lived with disability increased from 4.8% to 8.8%. The age-standardized DALY rate only slightly decreased (AAPC=-0.3%; which increased during 2016-2019, AAPC=1.6%). In 2019, the age-standardized DALY rate for breast cancer in China was 278.0/100 000. The DALYs were 2.88 million (accounting for 14.2% of the global burden and 12.1% of all female cancers burden in China), 26.5% of which attributed known risk factors (overweight and obesity were the largest: 0.34 million DALYs, but some common breast cancer risk factors were not available on the platform, such as menstruation and fertility). In 2050, the prediction suggests that the total DALYs caused by female breast cancer in China will reach 3.80 million person-years-5.16 million person-years, increasing 32.1%-79.4% over 2019. From 2000 to 2019, the peak age of DALYs and DALY rate became older, and the DALYs among females aged 65 years and above increased faster than those younger than 65 years (AAPC were 4.8% and 1.3%, respectively). In 2019, females aged 45-74 (the starting age recommended by local guidelines for breast cancer screening) contributed 74.3% of the total DALYs.Conclusions:Over the past 20 years, the age-standardized DALY rate for breast cancer in female populations in China has not changed obviously. Without the continuous expansion of effective intervention and population aging, the burden of DALYs for female breast cancer in China will increase. DALYs for breast cancer attributed leading risk factors were still limited.