The value of magnetic resonance imaging in diagnosis and size assessment of in situ and small invasive breast carcinoma

Background The value of magnetic resonance imaging (MRI) in diagnosis and size assessment of ductal carcinoma-in-situ (DCIS) and DCIS with small (<10 mm) invasive carcinoma was evaluated. Methods Fifty-four patients with DCIS and 12 patients with DCIS and small invasive carcinoma were included. Mammographic (N = 64) and MRI (N = 22) images were retrospectively reviewed. Correlation coefficients were calculated to assess differences in size between imaging and histopathologic examination. Results Mammographic rate of detection for DCIS was 48/52 (92%) and for DCIS with small invasive carcinoma, 10/12 (83%). MRI revealed 1 false negative case and the rate of detection for DCIS was 16/17 (94%). Correlation of mammographic size with histopathologic size was r = .44 (P< .01) and r = 0.49 (P = .03) for MRI. Mammography underestimated lesion size by 5 mm or more in 47%, whereas with MRI size was adequately assessed in 43% and overestimated in 38%. Conclusions DCIS can be visualised on MRI with high sensitivity, although tumor size can be overestimated.