THE INFLUENCE OF PREVIOUS FILMS ON SCREENING MAMMOGRAPHIC INTERPRETATION AND DETECTION OF BREAST-CARCINOMA

Aim: To establish if the availability of previous mammograms improves the detection rate of carcinomas and reduces supplementary examination s in the National Health Service Breast Screening Programme (NHSBSP). Method: Eight radiologists with varying experience but an interest in reporting mammograms reported 100 mammograms on two occasions, at leas t 1 month apart, In this selection of 100 mammograms we randomly inser ted 12 abnormal films, with both benign and malignant changes present, These were chosen retrospectively with histological correlation of th e abnormality. On the first occasion only the current films were revie wed, however, on the second occasion previous films mere available for comparison, The films were viewed under standard viewing conditions, and the participants mere asked to comment if they required further vi ews or would refer the patient for either an ultrasound examination or surgical referral. Results: Receiver operating curves (ROC) mere cons tructed for the group's overall performance on each of the occasions a nd there was no difference in the curves, This indicates that the pres ence of previous films did not improve diagnostic accuracy, The presen ce of previous films did, however, lead to a significant reduction in the number of additional views and ultrasound examinations that mould have been requested, The most significant reductions occurred in the g roup of normal mammograms. Conclusion: The presence of previous mammog rams does not lead to an improvement in diagnostic accuracy, However, the presence of previous films led to significant reduction in additio nal examinations and ultrasound examinations.