gms | German Medical Science

The objective of this study was to define situations where core needle biopsy (CNB) of breast lesions may fail to yield a reliable histological diagnosis of a sonographically detectable breast lesions. Over a 28 months period, 962 sonographically guided CNBs were performed under US validation to assess 962 breast lesions. All biopsies were carried out with an automated core biopsy device fitted with 14-gauge (22 mm excursion) needles. Data of 962 biopsied breast lesions were gathered. Surgical follow-up was available for 659 lesions. Breast malignancies were diagnosed by ultrasound-guided CNB with a sensitivity of 98,2%. Overall histological agreement between CNB specimen and finding at excision biopsy was highly significant (p < 0,001). CNB misses occurred in lesions that were sonographically classified as masses and central hits of the needle. None of the recorded parameter like lesion size, palpability or number of biopsies was significantly different in the group of malignant lesions not recognized by CNB-based diagnosis. In our study 5 of 11 (45%) core misses were observed in scars from former excision biopsies (more than one year before) where either sonographic assessment of the lesion or visualization of the needle was impaired. This is supported by our observation that core biopsy misses later diagnosed to be invasive carcinomas had been expected to be scar tissue from former surgeries. Our results demonstrate that CNB is a very safe method to obtain a reliable histological diagnosis of breast lesions. Furthermore CNB which causes no visible scaring that might impair further diagnostic breast assessment should replace surgical biopsy as the standard technique to remove tissue for initial histological assessment of breast lesions.