Purpose: To assess the effect of a second diagnostic reading of breast imaging at a university department of radiology.
Material and methods: The diagnostic reports of first readers from different private radiology practices and the reports of second readers from the university department of radiology were compared with the histological results (n = 214) and outcome of follow-ups for 4 years (n = 74) in 236 patients (mean age 55 years). BI-RADS categories were used for this purpose. The initial examinations had been performed because of symptoms (n = 117), early detection outside an organized screening program (n = 102), evaluations following breast cancer therapy (n = 13) and unknown primary tumors (n = 4). In addition, the number of complementary examinations and the influence of a second reading on patient management were evaluated.
Results: A total of 140 lesions were malignant and 148 were benign. Of the 288 lesions, 49 % were classified identically in the second reading; 36 % (79/217) of the lesions initially classified as BI-RADS 4 and 5 were downgraded to benign; and 41 % (29/71) of the lesions classified as BI-RADS 1 to 3 were upgraded as suspected of being malignant. The kappa value between the first and second readers was 0.34 with respect to each BI-RADS category separately and 0.18 with respect to categories 1 to 3 (benign) versus 4 and 5 (malignant). A second reading increased the sensitivity from 81 % (114/140) to 96 % (135/140) and the specificity from 30 % (45/148) to 78 % (116/148). Second readers detected 23 additional malignant lesions, changed two lesions correctly classified as malignant to benign categories and caused 6 additional false-positive findings. In all, 38 surgical biopsies could be prevented, one biopsy was erroneously delayed and three unnecessary excisional biopsies were initiated. In the study group, 49 MRI examinations revealed 5 additional malignant lesions and positively influenced surgical planning in 28 patients. In addition to these MRI examinations, 221 patients were examined using ultrasonography, 62 patients using complementary mammography, and 7 using galactography.
Conclusion: The benefit of a second reading outweighs the expenditure.