[Stereotactic vacuum-assisted breast biopsy--success, histologic accuracy, patient acceptance and optimizing the BI-RADSTM-correlated indication]

Histological underestimation of a 9-gauge stereotactic vacuum-assisted breast biopsy system compared with surgical excision at a tertiary hospital in South Africa

Background: Breast cancer is a major cause of morbidity and mortality worldwide. Certain lesions encountered on mammography require histological assessment of biopsy samples to identify benign versus malignant disease. Stereotactic vacuum-assisted breast biopsy (SVAB) is a useful technique, especially for non-palpable microcalcific lesions, and was introduced at our institution in 2011.Objectives: To determine whether the histological underestimation from 9-gauge SVABs performed at our institution is within acceptable limits.Method: In this cross-sectional study, 9-gauge stereotactic biopsy histology results and breast imaging and reporting data system (BI-RADS) findings of 158 lesions (from 153 patients) were analysed and the histological findings compared with surgical excision histology results (54 lesions) to determine histological underestimation (upgrade rates).Results: One out of eight cases of ductal carcinoma in situ (DCIS) was underestimated, yielding a DCIS underestimation rate of 12.5%.Conclusion: The DCIS underestimation obtained from the present study in our institution was on a par with other authors’ findings and was therefore within acceptable limits. Atypical ductal hyperplasia underestimation could not be reliably obtained with the small study population.Keywords: Stereotactic vacuum assisted breast biopsy; histological underestimation; histological upgrade

Vacuum-assisted breast biopsy with 7-gauge, 8-gauge, 9-gauge, 10-gauge, and 11-gauge needles: how many specimens are necessary?

BACKGROUND

Published national and international guidelines and consensus meetings on the use of vacuum-assisted biopsy (VAB) give different recommendations regarding the required numbers of tissue specimens depending on needle size and imaging method.

PURPOSE

To evaluate the weights of specimens obtained with different VAB needles to facilitate the translation of the required number of specimens between different breast biopsy systems and needle sizes, respectively.

MATERIAL AND METHODS

Five different VAB systems and seven different needle sizes were used: Mammotome® (11-gauge (G), 8-G), Vacora® (10-G), ATEC Sapphire™ (9-G), 8-G Mammotome® Revolve™, and EnCor Enspire® (10-G, 7-G). We took 24 (11-G) or 20 (7-10-G) tissue cores from a turkey breast phantom. The mean weight of a single tissue core was calculated for each needle size. A matrix, which allows the translation of the required number of tissue cores for different needle sizes, was generated. Results were compared to the true cumulative tissue weights of consecutively harvested tissue cores.

RESULTS

The mean tissue weights obtained with the 11-G / 10-G Vacora® / 10-G Enspire® / 9-G / 8-G Original / 8-G Revolve™ / 7-G needles were 0.084 g / 0.142 g / 0.221 g / 0.121 g / 0.192 g / 0.334 g / 0.363 g, respectively. The calculated required numbers of VAB tissue cores for each needle size build the matrix. For example, the minimum calculated number of required cores according to the current German S3 guideline is 20 / 12 / 8 / 14 / 9 / 5 / 5 for needles of 11-G / 10-G Vacora® / 10-G Enspire® / 9-G / 8-G Original / 8-G Revolve™ / 7-G size. These numbers agree with the true cumulative tissue weights.

CONCLUSION

The presented matrix facilitates the translation of the required number of VAB specimens between different needle sizes and thereby eases the implementation of current guidelines and consensus recommendations into clinical practice.

BI-RADS categorisation of 2,708 consecutive nonpalpable breast lesions in patients referred to a dedicated breast care unit

OBJECTIVES

To determine the malignancy rate of nonpalpable breast lesions, categorised according to the Breast Imaging Reporting and Data System (BI-RADS) classification in the setting of a Breast Care Unit.

METHODS

All nonpalpable breast lesions from consecutive patients referred to a dedicated Breast Care Unit were prospectively reviewed and classified into 5 BI-RADS assessment categories (0, 2, 3, 4, and 5).

RESULTS

A total of 2708 lesions were diagnosed by mammography (71.6%), ultrasound (8.7%), mammography and ultrasound (19.5%), or MRI (0.2%). The distribution of the lesions by BI-RADS category was: 152 in category 0 (5.6%), 56 in category 2 (2.1%), 742 in category 3 (27.4%), 1523 in category 4 (56.2%) and 235 in category 5 (8.7%). Histology revealed 570 malignant lesions (32.9%), 152 high-risk lesions (8.8%), and 1010 benign lesions (58.3%). Malignancy was detected in 17 (2.3%) category 3 lesions, 364 (23.9%) category 4 lesions and 185 (78.7%) category 5 lesions. Median follow-up was 36.9 months.

CONCLUSION

This pragmatic study reflects the assessment and management of breast impalpable abnormalities referred for care to a specialized Breast Unit. Multidisciplinary evaluation with BI-RADS classification accurately predicts malignancy, and reflects the quality of management. This assessment should be encouraged in community practice appraisal.

Accuracy of classification of breast ultrasound findings based on criteria used for BI-RADS

OBJECTIVE

To assess the accuracy of categorization of breast ultrasound findings based on scoring for malignancy using the sonographic breast imaging-reporting and data system (BI-RADS).

METHODS

Breast ultrasound was performed in 2462 patients between 2001 and 2004 at our unit. Sonographic findings were scored using analog criteria as in BI-RADS for breast ultrasound (mass shape, margin, orientation, posterior acoustic features, lesion boundary, echo pattern). Each lesion was described using these features and classified into categories 1 to 5 according to the BI-RADS for breast ultrasound. Categorization and biopsy results were compared.

RESULTS

In twenty-two (0.9%) patients breast ultrasound could not be evaluated because of extreme density of tissue. Normal breast ultrasound belonging to Category 1 was found in 871 (35.4%) patients. Simple cysts classified as Category 2 were observed in 712 (28.9%) women. In 491 (19.9%) patients, apparently benign solid masses (Category 3) were found. Suspicious masses were observed in 225 (9.1%) women and masses highly suggestive of malignancy were found in 141 (5.7%) patients (Categories 4 and 5, respectively). Histological examinations were available from 84 (17.1%) masses that had been classified by BI-RADS as Category 3, in 97 (43.1%) from Category 4 and 106 (75.2%) from Category 5. Accordingly, the rate of malignant findings was 1.2% (n = 1) in Category 3, 17% (n = 16) in Category 4 and 94% (n = 100) in Category 5.

CONCLUSION

Scoring breast ultrasound findings for malignancy based on criteria used for BI-RADS breast ultrasound has a high accuracy, comparable to that obtained by BI-RADS for mammography.

The adjacent vessel on dynamic contrast-enhanced breast MRI

OBJECTIVE

The purpose of this study was to investigate whether an adjacent vessel leading to an enhancing lesion seen on subtraction images can help differentiate malignant from benign breast lesions and therefore increase the specificity of breast MRI.

MATERIALS AND METHODS

The study included 132 histologically verified lesions (71 malignant lesions, 10 pure carcinoma in situ, and 51 benign lesions) enhancing on dynamic breast MRI before biopsy. The lesions were evaluated by three radiologists in a double-blinded manner. The presence of an adjacent vessel was supposed if at least two observers voted positively.

RESULTS

Sixty-one (85.9%) of 71 malignant lesions, six (60%) of 10 carcinomas in situ, and 10 (19.6%) of 51 benign lesions were associated with an adjacent vessel, which differed significantly (p < 0.001) between benign and malignant lesions (the latter with and without including pure carcinoma in situ), leading to a positive predictive value of 85.9% (87% including pure carcinomas in situ), a negative predictive value of 80.4% (74.5% including pure carcinomas in situ), an accuracy of 83.2% (81.6% including pure carcinomas in situ), a sensitivity of 85.9% (82.7% including carcinomas in situ), and a specificity of 80.4% for this sign concerning malignancy.

CONCLUSION

The presence of an adjacent vessel seen on subtraction images promises to be a good marker for malignancy and can therefore help increase the specificity of breast MRI.

Potential MRI Interpretation Model: Differentiation of Benign from Malignant Breast Masses

OBJECTIVE

Our objective was to increase the accuracy of breast MRI using a semiquantitative analysis of typical MRI features and their diagnostic potential. The prevalence of recently reported MRI signs of breast lesions were analyzed and compared with other well-known signs.

CONCLUSION

New MRI features, especially from T2-weighted images, are promising for more reliable and accurate interpretation of breast lesions. Prospective studies of these findings are required to define cut-off values and test clinical practicality.

Stereotactic vacuum-assisted breast biopsies in 500 women with microcalcifications: radiological and pathological correlations

AIM

We compared radiological assessment with pathological diagnoses in 500 consecutive vacuum-assisted breast biopsies performed for microcalcifications.

METHODS

Lesions were biopsied using a 11-gauge mammotome device. Before biopsy, microcalcifications were classified according to the Breast Imaging Reporting and Data System (BI-RADS). Histopathological and radiological diagnosis were compared.

RESULTS

Histopathology revealed 333 (67%) benign lesions. Benign lesions were classified as BI-RADS 3 in 19%, and as suspicious in 35%. 167 lesions (33%) were malignant. Malignant lesions were classified as suspicious or highly suggestive of malignancy in 63%. Frequency of malignancy in BI-RADS categories 4 and 5 was 35% and 100%, respectively. In BI-RADS 3 microcalcifications, the malignancy frequency was 19%. The mammographic features with the highest positive predictive value for malignancies were pleomorphic morphology (42%) and a linear or segmental distribution (51%). The microcalcification morphology was not reliably able to predict malignancy.

CONCLUSION

In this study, BI-RADS 3 microcalcification lesions had a malignancy rate that is higher than previously reported. Vacuum-assisted biopsy is useful in any indeterminate and suspicious microcalcifications and provides maximum information before any operative intervention.

Applications and literature review of the BI-RADS classification

The Breast Imaging Reporting and Data System (BI-RADS) of the American College of Radiology (ACR) is a tool created to reduce variability in the terminology used in mammographic reports. An illustration of mammographic examples from our institution interpreted according to the BI-RADS lexicon of the American College of Radiology (ACR) is presented. A literature review concerning the usefulness and limitations of the BI-RADS lexicon is given.