What is the yield of breast MRI in the assessment of palpable breast findings?

Aim: To examine the contribution of magnetic resonance imaging (MRI) to characterise palpable breast masses after conventional imaging was found to be non-contributory.

Materials and methods: The breast MRI database was reviewed for studies performed between January 2010 and December 2015 for the clinical indication of palpable breast finding with negative standard imaging. Medical files were reviewed for demographic data, clinical information, radiology, and pathology reports. Benign versus malignant outcomes were determined at histopathology or a minimum of 12 month follow-up.

Results: Investigation of palpable breast finding was the clinical indication for 167 of 7,782 (2%) examinations. Thirty-two (19%) women in the study had positive MRI findings. Most (20, 63%) findings corresponded to the palpable area, resulting in three carcinomas being diagnosed. Only one carcinoma required MRI-guided biopsy for diagnosis. Eighteen women with negative MRI underwent ultrasound-guided biopsy from the palpable area, which resulted in a diagnosis of one carcinoma. One carcinoma was incidentally detected in another location. Within the present population, the sensitivity for detecting malignancy was 80%, specificity 78%, negative predictive value 99%, and positive predictive value 13%.

Conclusions: Although cancer was found in four cases in the palpable area, the biopsy was directed using MRI in only one case. A new palpable finding with non-contributory standard imaging should prompt a needle-guided biopsy and not further evaluation using MRI.