Diagnosis and management of high-risk breast lesions: Aristotle's dilemma

Stereotactic breast biopsies: Radiological-pathological concordance in a South African referral unit

Background: Stereotactic breast biopsies have become the gold standard for tissue diagnosis in non-palpable, sonographically occult breast abnormalities seen on mammogram. Only limited data exist in South Africa on the correlation between imaging findings and stereotactic biopsy histology.Objectives: To describe the mammographic findings and histological diagnosis in patients who underwent stereotactic breast biopsy at a referral hospital. In addition, to evaluate the proportion of malignancy in each Breast Imaging Reporting and Data System (BI-RADS) category.Method: A retrospective review of stereotactic breast biopsies was performed. Imaging characteristics (including BI-RADS category) and histological diagnosis were recorded. Using histopathology, cases were classified as benign, high-risk or malignant.Results: A total of 131 biopsies, from 123 patients, were included in the study. Most biopsies were performed on asymptomatic patients (79.3%, 104/131). The majority were categorised as BI-RADS 4 and demonstrated calcifications. Histology revealed a malignant diagnosis in 40 (30.5%) patients, a high-risk lesion in 8 (6.1%) patients and a benign diagnosis in 83 (63.4%) patients. There was a stepwise increase in the proportion of malignancy from BI-RADS category 3 to 5. When compared with surgical histology, the stereotactic biopsies demonstrated an overall ductal carcinoma in situ (DCIS) underestimation rate of 10.3%.Conclusion: Despite resource restrictions, stereotactic breast biopsies performed in a South African context produce radiological-pathological concordance in keeping with BI-RADS guidelines, as well as with local and international studies.

Predictive factors for breast lesion excision system (BLES) accuracy and safety in stereotactic biopsy of suspicious calcifications

AIM

To retrospectively assess the effectiveness and safety of BLES stereotactic biopsy of suspicious calcifications and investigate possible predictive factors for underestimation.

METHODS AND MATERIALS

Between January 2014 and January 2016, 400 biopsies of suspicious calcifications were performed in our Department using the BLES stereotactic device. The mean age of our population was 58.5 years (range 39-78 years). The final surgical results were used as gold standard. The effectiveness of the method was statistically evaluated. Mammographic size, grade, molecular type, and presence of comedo type/necrosis were assessed as predictive factors.

RESULTS

90/400 (22.5%) cases were cancers (20% invasive cancers, 80% non-invasive cancers). 38/400 cases were atypical lesions (9.5%). No underestimation was found in atypical lesions that underwent surgery (29/38 cases). Downgrade was achieved in 45.5% of cases (with complete removal in 34.4%), concordance in 43.3%, and upgrade was found in 15.5% of the cases; the initial mammographic size and the grade of the cancers were found to be statistically significant predictive factors. The total complication rate was 8.75%.

CONCLUSIONS

Breast lesion excision system is a highly accurate and safe stereotactic biopsy technique of suspicious calcifications with low underestimations and high downgrade/removal rates with the potential to alter the final surgical decision in selected cases.

Role of one-pass breast lesion excision system in complete excision of high-risk breast lesions with atypia expressed as clusters of microcalcifications

PURPOSE

To assess the role of the breast lesion excision system (BLES) in complete removal of clusters of microcalcifications found on mammogram proved histologically to be high-risk lesions with cell atypia.

METHODS AND MATERIALS

Three hundred ninety-four consecutive women (mean age 58.5 years, range 39-78 years) with 400 clusters of suspicious microcalcifications underwent stereotactic biopsy using the intact BLES device between January 2014 and January 2016. All cases proved histologically to be high-risk lesions were subsequently assessed for complete removal. The underestimation rate was also assessed.

RESULTS

Thirty-eight out of 400 (9.5%) lesions were high-risk lesions with atypia with mean size 7.63 mm (st. dev. = 4.03 mm) which was within the size that the BLES needle can excise (20 mm). Four (10.5%) papillomas with atypia, 14 (36.8%) cases with flat epithelial atypia (FEA), 10 (26.3%) cases with lobular intraepithelial neoplasia (LIN-LIN 1, LIN 2), 8 (21.2%) with atypical ductal hyperplasia (ADH) and 2 (5.3%) cases with mucocele-like lesions (MLL) with atypia were found. Twenty-nine out of 38 lesions had subsequent surgery. Complete excision was achieved in 23/29 lesions (79.3%). No underestimation was found. Two-year mammographic stability was found in all lesions. Non-parametric statistical analysis showed no other significant predictive factor for complete excision apart from the distance of the lesions from the specimen margins (p = 0.031 Mann-Whitney test).

CONCLUSION

One-pass BLES intact biopsy technique is a safe method of complete removal of high-risk atypical lesions with high accuracy rates for certain histologies and could be potentially used as an alternative excision method to diagnostic surgery in selected cases.

KEY POINTS

• Breast lesion excision system (BLES) is an image-guided biopsy technique that uses radiofrequency to remove an intact piece of tissue including the target breast neoplasm. • Breast lesion excision system (BLES) under stereotactic guidance is able to accurately biopsy high-risk breast lesions expressed mammographically as clusters of suspicious microcalcifications. • BLES under stereotactic guidance is an accurate technique for en bloc excision of selected cases of small clusters of suspicious microcalcifications proved to be high-risk lesions with histopathologically disease-free margins of excision.

Upgrade rates of high-risk breast lesions diagnosed on core needle biopsy: a single-institution experience and literature review

Optimal management of high-risk breast lesions detected by mammogram yielding atypical ductal hyperplasia, flat epithelial atypia, atypical lobular hyperplasia, lobular carcinoma in situ, and radial scar without atypia on core needle biopsy is controversial. This is a single-institution retrospective review of 5750 core needle biopsy cases seen over 14.5 years, including 249 (4.3%), 72 (1.3%), 50 (0.9%), 37 (0.6%), and 54 (0.9%) cases of atypical ductal hyperplasia, flat epithelial atypia, atypical lobular hyperplasia, lobular carcinoma in situ, and radial scar without atypia, respectively. Patient age, radiologic characteristics, needle gauge, and excision diagnoses were recorded. Of 462 high-risk cases analyzed, 333 (72%) underwent excision. Upgrade rate to ductal carcinoma in situ, pleomorphic carcinoma in situ, or invasive mammary carcinoma was 18% for atypical ductal hyperplasia, 11% for flat epithelial atypia, 9% for atypical lobular hyperplasia, 28% for lobular carcinoma in situ, and 16% for radial scar. Carcinoma diagnosed on excision was more likely to be in situ than invasive, and if invasive, more likely to be low grade than high grade. Overall, cases that were benign (vs high risk or carcinoma) on excision were less likely to have residual calcifications after biopsy (17% vs 27%, P=0.013), and more likely to have a smaller mass size (<1 cm) (82% vs 50%, P=0.001). On subgroup analysis, atypical ductal hyperplasia cases that were benign (vs high risk or carcinoma) on excision were more likely to have smaller mass size (<1 cm) (P=0.025). Lobular neoplasia diagnosed incidentally (vs targeted) on core needle biopsy was less likely to upgrade on excision (5% vs 39%, P=0.002). A comprehensive literature review was performed, identifying 116 studies reporting high-risk lesion upgrade rates, and our upgrade rates were similar to those of more recent larger studies. Careful radiological-pathological correlation is needed to identify high-risk lesion subgroups that may not need excision.