Cancelled stereotactic biopsy of calcifications not seen using the stereotactic technique: do we still need to biopsy?

Diagnostic Contrast-Enhanced Mammography Performed Immediately Prior to Same-Day Biopsy: An Analysis of Index Lesion Enhancement Compared to Histopathology and Follow-up in Patients With Suspicious Ultrasound Findings

Objective

To measure the diagnostic performance of contrast-enhanced mammography (CEM) for the index lesion when it is performed the same day prior to biopsy in patients with suspicious findings at US.

Methods

This IRB-approved retrospective study compared radiologist original reports of the presence or absence of index lesion enhancement on CEM to biopsy results and follow-up. The most suspicious lesion or the larger of equally suspicious lesions recommended for biopsy by US after a diagnostic workup including mammography was considered the index lesion. CEM exams were performed the same day, immediately prior to the scheduled biopsy, as requested by the radiologist recommending the biopsy. Numeric variables were summarized with means and standard deviations, or medians and the minimum and maximum, where appropriate.

Results

Biopsy demonstrated cancer in 64.7% (200/309) of index lesions. Of these, 197/200 demonstrated enhancement for a sensitivity of 98.5% (95% CI: 95.7%-99.7%) (197/200) and the negative predictive value of CEM for non-enhancing index lesions was 95.1% (58/61; 95% CI: 86.1%-98.4%). The three false negative exams were two grade 1 ER+ HER2- invasive ductal cancers that were 6 mm and 7 mm in size, and a 3-mm grade 2 ductal carcinoma in situ in a complex cystic and solid mass. False positive exams made up 20.6% (51/248) of the positive exams.

Conclusion

Diagnostic CEM showed high sensitivity and specificity for cancer in lesions with suspicious US findings. CEM may reduce the need for some biopsies, and negative CEM may support a true negative biopsy result.

Failure of stereotactic core needle biopsy in women recalled for suspicious calcifications at screening mammography: frequency, causes, and final outcome in a multi-institutional, observational follow-up study

OBJECTIVES

We determined the failure rate of stereotactic core needle biopsy (SCNB) and its causes and final outcome in women recalled for calcifications at screening mammography.

METHODS

We included a consecutive series of 624,039 screens obtained in a Dutch screening region between January 2009 and July 2019. Radiology reports and pathology results were obtained of all recalled women during 2-year follow-up.

RESULTS

A total of 3495 women (19.6% of 17,809 recalls) were recalled for suspicious calcifications. SCNB was indicated in 2818 women, of whom 12 had incomplete follow-up and another 12 women refused biopsy. DCIS or invasive cancer was diagnosed in 880 of the remaining 2794 women (31.5%). SCNB failed in 62 women (2.2%, 36/2794). These failures were mainly due to a too posterior (n = 30) or too superficial location (n = 17) of the calcifications or calcifications too faint for biopsy (n = 13). Of these 62 women, 10 underwent surgical biopsy, yielding one DCIS (intermediate grade) and two invasive cancers (one intermediate grade and one high grade) and another two women were diagnosed with DCIS (both high grade) at follow-up. Thus, the malignancy rate after SCNB failure was 8.1% (5/62). Calcifications were depicted neither at SCNB specimen radiography nor at pathology in 16 women after (repeated) SCNB (0.6%, 31/2732). None of them proved to have breast cancer at 2-year follow-up.

CONCLUSIONS

The failure rate of SCNB for suspicious calcifications is low but close surveillance is warranted, as breast cancer may be present in up to 8% of these women.

KEY POINTS

• The failure rate of stereotactic core needle biopsy (SCNB) for calcifications recalled at screening mammography was 2.2%. • Failures were mainly due to calcifications that could not be reached by SCNB or calcifications too faint for biopsy. • The management after failed SCNB was various. At least, close surveillance with a low threshold for surgical biopsy is recommended as breast cancer may be present in up to 8% of women with SCNB failure.

Preoperative breast MRI features associated with positive or close margins in breast-conserving surgery

PURPOSE

To determine preoperative magnetic resonance imaging (MRI) features associated with positive or close margins in patients with breast cancer who underwent breast-conserving surgery (BCS).

MATERIALS AND METHODS

A retrospective review identified 249 patients with invasive ductal carcinoma (IDC) who underwent preoperative MRI and BCS as a primary procedure between 2008 and 2010. The MR images were reviewed for descriptions of findings with no new interpretations made. Margins were defined as positive (tumor touching the inked specimen margin), close (<2 mm tumor-free margin), or negative (≥2 mm tumor-free margin). Multivariate logistic regression analysis was performed to evaluate imaging and clinical factors predictive of positive or close margins.

RESULTS

Of the 249 patients, 83 (33.3%) had positive or close margins and 166 (66.7%) had negative margins on the initial BCS specimen. Multivariate analysis showed that multifocal disease (odds ratio, 4.8; 95% CI, 1.9-12.2; p =  0.001), nonmass enhancement lesion (odds ratio, 3.0; 95% CI, 1.5-6.2, p =  0.003), greater background parenchymal enhancement (odds ratio, 2.5; 95% CI, 1.1-5.6; p =  0.023), larger lesion size (odds ratio, 1.3; 95% CI, 1.0-1.7, p =  0.032), and presence of ductal carcinoma in situ on needle biopsy (odds ratio, 2.4; 95% CI, 1.3-4.6; p = 0.008) were independent predictors of positive or close margins.

CONCLUSIONS

Multifocal disease, nonmass enhancement lesion, or greater background parenchymal enhancement on preoperative breast MRI were significantly associated with positive or close margins. Identifying these MRI features before surgery can be helpful to reduce the reoperation rate in BCS.

Feasibility of Vacuum-Assisted Breast Cone-Beam CT-Guided Biopsy and Comparison With Prone Stereotactic Biopsy

OBJECTIVE

The feasibility of breast vacuum-assisted biopsy (VAB) guided by cone-beam CT (CBCT) was assessed. The initial clinical performance of CT-guided breast VAB was compared with that of established prone stereotactic VAB.

MATERIALS AND METHODS

In this retrospective clinical trial, VABs were performed for women with mammographically suspicious breast lesions using a dedicated breast CBCT protocol. The technical success rate, total intervention time, and complications were documented and compared with examinations performed by prone stereotactic VAB.

RESULTS

Between June 2015 and March 2016, 65 patients with 68 target lesions underwent image-guided VAB. CT-guided VAB was performed for 29 patients with 31 lesions. Thirty-six patients with 37 lesions underwent prone stereotactic VAB. The type of lesion was not different between the two groups (p = 0.135). Technical success rate was achieved in 31 of 33 lesions (93.9%) with CT-guided VAB versus 37 of 38 lesions (97.4%) with prone stereotactic VAB. The mean (± SD) total intervention time was 22.7 ± 8.4 minutes for CT-guided VAB versus 28.8 ± 9.4 minutes for prone stereotactic VAB (p < 0.05). Reidentifying and targeting lesions took about the same time for both systems (p = 0.362). The time for tissue sampling was significantly faster with CT-guided VAB (p < 0.05). No major complications were observed with either system.

CONCLUSION

CT-guided VAB is safe and feasible using the currently available breast CBCT protocol. The mean total intervention time to complete VAB and the time for tissue sampling was significantly faster using CT-guided VAB in comparison with prone stereotactic VAB.

Surgical biopsy is still necessary for BI-RADS 4 calcifications found on digital mammography that are technically too faint for stereotactic core biopsy

The purpose of this study was to evaluate the outcome of faint BI-RADS 4 calcifications detected with digital mammography that were not amenable to stereotactic core biopsy due to suboptimal visualization. Following Institutional Review Board approval, a HIPAA compliant retrospective search identified 665 wire-localized surgical excisions of calcifications in 606 patients between 2007 and 2010. We included all patients that had surgical excision for initial diagnostic biopsy due to poor calcification visualization, whose current imaging was entirely digital and performed at our institution and who did not have a diagnosis of breast cancer within the prior 2 years. The final study population consisted of 20 wire-localized surgical biopsies in 19 patients performed instead of stereotactic core biopsy due to poor visibility of faint calcifications. Of the 20 biopsies, 4 (20% confidence intervals 2, 38%) were malignant, 5 (25%) showed atypia and 11 (55%) were benign. Of the malignant cases, two were invasive ductal carcinoma (2 and 1.5 mm), one was intermediate grade DCIS and one was low-grade DCIS. Malignant calcifications ranged from 3 to 12 mm. The breast density was scattered in 6/19 (32%), heterogeneously dense in 11/19 (58%) and extremely dense in 2/19 (10%). Digital mammography-detected faint calcifications that were not amenable to stereotactic biopsy due to suboptimal visualization had a risk of malignancy of 20%. While infrequent, these calcifications should continue to be considered suspicious and surgical biopsy recommended.

Digital breast tomosynthesis-guided vacuum-assisted breast biopsy: initial experiences and comparison with prone stereotactic vacuum-assisted biopsy

PURPOSE

To use digital breast tomosynthesis (DBT)-guided vacuum-assisted biopsy (VAB) to sample target lesions identified at full-field digital screening mammography and compare clinical performance with that of prone stereotactic (PS) VAB.

MATERIALS AND METHODS

In this institutional review board-approved study, 205 patients with 216 mammographic findings suspicious for cancer were scheduled to undergo mammography-guided VAB. Written informed consent was obtained. PS VAB was performed in 159 patients with 165 target lesions. DBT VAB was performed in 46 consecutive patients with 51 target lesions. Tissue-sampling methods and materials (9-gauge needles) were the same with both systems. For calcifications, specimen radiographs were obtained, and for masses or architectural distortions, control mammography or DBT was performed to confirm adequate target lesion sampling. χ(2) and Student t tests were used to compare biopsy time, and the Fisher exact test was used to compare lesion type distribution for DBT versus PS VAB.

RESULTS

Technical success was achieved in 51 of 51 lesions (100%) with DBT VAB versus 154 of 165 lesions (93%) with PS VAB. In one of 11 lesions in which PS VAB failed, DBT VAB was performed successfully. Mean time to complete VAB was 13 minutes ± 3.7 for DBT VAB versus 29 minutes ± 10.1 for PS VAB (P < .0001). Reidentifying and targeting lesions during PS VAB took longer than it did during DBT VAB (P < .0001). Tissue sampling took about the same time for PS VAB and DBT VAB (P = .067). Significantly more "low-contrast" (ie, uncalcified) target lesions were biopsied with DBT VAB (13 of 51 lesions) versus PS VAB (nine of 165 lesions) (P < .0002). No major complications were observed with either system. One patient who underwent DBT VAB in the sitting position and one patient who underwent PS VAB developed self-limiting vasovagal reactions.

CONCLUSION

Clinical performance of DBT VAB was significantly superior to PS VAB. Because DBT VAB allows use of the full detector size for imaging and provides immediate lesion depth information without requiring triangulation, it facilitates target lesion reidentification and sampling of even low-contrast targets, such as uncalcified masses.