Breast, Mammography, Screening, Cancer, Retrospective, Observational, Performed at one institution
T. Presa 1, M. Moreland2, A. Kumar3, J. K. Juttla4; 1London/UK, 2Maidenhead/UK, 3Slough/UK, 4Harrow/UK
Methods and materials
This was a retrospective analysis of the G3 interval cancers diagnosed in our breast screening unit from April 2016 to April 2019. The screening population of the Unit is seventy eight thousand.
The breast screening programme in the UK offers screening once every three years to woman between 50 to 70 years old, with some extensions in certain trials to women aged 47 to 73 years old.
All the G3 interval cancers were anonymised and analysed by a group of six breast radiologists and classified into three categories ( Fig. 1 ):
Category 1: Interval cancer with a normal screening mammogram. None of the radiologists would have recalled the screening mammogram ( Fig. 2 ).
Category 2: Interval cancer with subtle findings. In hindsight and with the knowledge that the patient has a breast cancer, there were some subtle findings in the screening mammogram and some radiologists would have recalled the screening mammogram ( Fig. 3 ).
Category 3: Missed cancer. There were signs of cancer in the screening mammogram, and the entire group of radiologists would have recalled the screening mammogram ( Fig. 4 ).
The category 2 or 3 interval cancers were reviewed. The screening mammogram was compared to previous mammograms in order to analyse early radiological findings.
Other prognostic factors reviewed were the time between screening and presentation, the size of the tumour and the hormonal status.