Outcome analysis of 9-gauge MRI-guided vacuum-assisted core needle breast biopsies

The purpose of this article is to correlate 9-gauge MRI-guided vacuum-assisted breast biopsy with surgical histologic findings to determine the upgrade rate and to correlate the frequency of MRI-guided vacuum-assisted breast biopsy cancer diagnosis with breast MRI indications and enhancement characteristics of targeted lesions.

A database search was performed of all MRI-guided vacuum-assisted breast biopsies performed from January 1, 2005, to September 31, 2010. The breast MRI indications, history, age, risk factors, lesion size, enhancement characteristics, and pathologic diagnoses at MRI-guided vacuum-assisted breast biopsy and at surgery were documented. Fisher exact test and analysis of variance were used for statistical analysis.

A total of 218 lesions underwent MRI-guided vacuum-assisted breast biopsy in 197 women (mean age, 52 years; range, 28-76 years), of which 85 (39%) had surgical correlation. Of the 218 lesions, 48 (22%) were malignant, 133 (61%) were benign, and 37 (17%) were high risk according to MRI-guided vacuum-assisted breast biopsy. Ten of 85 lesions (12%) were upgraded to malignancy at surgery, with a final malignancy rate of 25%. The frequency of malignancy was significantly higher in patients presenting for diagnostic (50/177 [28%]) versus screening (4/41 [10%]; p < 0.05) evaluation, patients with ipsilateral cancer (22/49 [45%]; p < 0.001), and lesions with washout kinetics (34/103 [33%]; p < 0.05) and was relatively higher in lesions with nonmasslike enhancement (26/76 [34%]; p = 0.07), which represented ductal carcinoma in situ in the majority of cases (17/26 [65%]; p < 0.005).

Patients with ipsilateral cancer who have additional suspicious lesions identified on MRI require careful evaluation and biopsy to exclude additional sites of cancer that may impact surgical management.