Histological correlation of mammographically detected microcalcifications in stereotactic core biopsies

Utility of detection of breast calcifications with integrated real-time radiography system (IRRS) during digital breast tomosynthesis (DBT)-guided vacuum assisted biopsy (VAB): initial single-center experience

PURPOSE

To determine whether the presence of calcifications in specimens collected during stereotactic-guided vacuum-assisted breast biopsies (VABB) is sufficient to ascertain their adequacy for final diagnosis at pathology.

MATERIALS AND METHODS

Digital breast tomosynthesis (DBT)-guided VABBs were performed on 74 patients with calcifications as target. Each biopsy consisted of the collection of 12 samplings with a 9-gauge needle. This technique was integrated with a real-time radiography system (IRRS) which allowed the operator to determine whether calcifications were included in the specimens at the end of each of the 12 tissue collections through the acquisition of a radiograph of every sampling. Calcified and non-calcified specimens were separately sent to pathology and evaluated.

RESULTS

A total of 888 specimens were retrieved, 471 containing calcifications and 417 without. In 105 (22.2%) samples out of 471 with calcifications cancer was detected, while the remaining 366 (77.7%) were non-cancerous. Out of 417 specimens without calcifications 56 (13.4%) were cancerous, whereas 361 (86.5%) were non-cancerous. Seven hundred and twenty-seven specimens out of all 888 were cancer-free (81.8%, 95%CI 79-84%).

CONCLUSION

Although there is a statistical significative difference between calcified and non-calcified samples and the detection of cancer (p < 0.001), our study shows that the sole presence of calcifications in the specimens is not sufficient to determine their adequacy for final diagnosis at pathology because non-calcified samples can be cancerous and vice-versa. Ending biopsies when calcifications are first detected through IRRS could lead to false negative results.

Detectability of BI-RADS category 3 or higher breast lesions and reading time on mammography: comparison between 5-MP and 8-MP LCD monitors

Background Five-megapixel (MP) displays are recommended as soft copy devices for digital mammogram. An 8-MP liquid crystal display (LCD) (two 4-MP displays within one display) might offer the advantage of being able to view biplane mammography more easily than the dual planes of 5-MP LCDs. Purpose To compare detectability of Breast Imaging Reporting and Data System (BI-RADS) category 3 or higher lesions and reading time on mammography between 5- MP and 8-MP LCDs. Material and Methods The mammograms of 240 breasts of 120 patients including 60 breasts with BI-RADS category 3 or higher lesions and 180 breasts with normal or category 2 lesions were enrolled. All bilateral mammograms were displayed on bifacial 5-MP LCDs or an 8-MP LCD (two 4-MP displays within one display). Six radiologists assessed 240 breasts on each display. The observations were analyzed using receiver operating characteristic (ROC) analysis. A jack-knife method was used for statistical analysis. We employed a paired t-test to determine whether any significant differences existed in the reading time between two different displays. A P value < 0.05 was considered significant. Results The mean areas under the ROC curve obtained using 5-MP and 8-MP LCDs were 0.925 and 0.915, respectively, and there was no significant difference ( P = 0.46). There was also no significant difference in the reading time between two types of displays (57.8 min. vs. 51.5 min, P = 0.39). Conclusion The detectability of BI-RADS category 3 or higher lesions and reading time using an 8-MP LCD were comparable to those using a 5-MP LCD.

Randomized controlled trial of stereotactic 11-G vacuum-assisted core biopsy for the diagnosis and management of mammographic microcalcification

OBJECTIVE

To compare the accuracy of 11-G vacuum-assisted biopsy (VAB) with 14-G core needle biopsy (CNB) to diagnose mammographic microcalcification (MM) and effect on surgical outcomes.

METHODS

Following ethical approval, VAB and CNB (control) were compared in a randomized prospective study for first-line diagnosis of MM and subsequent surgical outcomes in two breast-screening units. Participants gave written informed consent. Exclusions included comorbidity precluding surgery, prior ipsilateral breast cancer and lesions >40 mm requiring mastectomy as first surgical procedure. The final pathological diagnosis was compared with the initial biopsy result. Quality-of-life (QOL) questionnaires were administered at baseline, 2, 6 and 12 months. 110 participants were required to show a 25% improvement in diagnosis with VAB compared with CNB (90% power).

RESULTS

Eligibility was assessed for 787 cases; 129 females recalled from the National Health Service breast screening programme were randomized. Diagnostic accuracy of VAB was 86% and that of CNB was 84%. Using VAB, 2/14 (14.3%) cases upgraded from ductal carcinoma in situ to invasion at surgery and 3/19 (15.8%) using CNB. Following VAB 7/16 (44%) cases required repeat surgery vs 7/24 (29%) after CNB. Both groups recorded significant worsening of functional QOL measures and increased breast pain at follow-up.

CONCLUSION

VAB and CNB were equally accurate at diagnosing MM, and no significant differences in surgical outcomes were observed.

ADVANCES IN KNOWLEDGE

The first randomized controlled study of VAB for diagnosis of microcalcification using digital mammography showed no difference in diagnostic accuracy of VAB and CNB, or in the proportion of participants needing repeat non-operative biopsy or second therapeutic operation to treat malignancy.

Microcalcifications Detected as an Abnormality on Screening Mammography: Outcomes and Followup over a Five-Year Period

Objectives. This study reviewed the outcome of women attending a breast screening program recalled for assessment of microcalcifications and examined the incidence of a breast carcinoma detected during the following five years in any of the women who were given a benign diagnosis at assessment. Method. A retrospective study consisted of 235 clients attending an Australian BreastScreen program in 2003, who were recalled for investigation of microcalcifications detected on screening mammography. Records for the following five years were available for 168 women in the benign outcome group including those who did not require biopsy at initial assessment. Results. Malignant disease was detected in 26.0% (n = 146) of the women who underwent biopsy. None of the women in the benign outcome group, with available five-year follow-up records, developed a subsequent breast cancer, arising from the calcifications initially recalled in 2003. Conclusions. This study highlights the effectiveness of an Australian screening program in diagnosing malignancy in women with screen detected microcalcification. This has been achieved by correctly determining 38% (n = 235) of the women as benign without the need for biopsy or early recall. A low rate of open surgical biopsies was performed with no cancer diagnoses missed at the time of initial assessment.

Microcalcifications of the breast: a mammographic-histologic correlation study using a newly designed Path/Rad Tissue Tray

The introduction of screening mammography has brought about a greater knowledge of early breast cancer characteristics. These improvements have led to a reduction in size of suspicious lesions and a shift from surgical to image-guided core needle biopsies (CNBs). Establishing correlation between histologic and imaging findings is required for accurate diagnosis. Currently, there are no standardized multidisciplinary protocols for evaluating such lesions. We correlated histologic and radiologic findings in mammographically detectable calcified lesions in CNBs using specially designed Path/Rad Tissue Trays (patent pending, University of Kansas). Evidence of calcification was analyzed in 440 with and without the use of tissue trays. After mammographic identification of the lesion, CNBs are harvested, placed in tissue trays, and x-rayed to confirm sampling of the lesion. Images of CNBs with calcifications are marked by the radiologists and sent to the pathologist along with the biopsies. Trays with CNBs are then placed into cassettes and sent to the laboratory where they are embedded without disturbing orientation. Identification and localization of targeted microcalcifications were accomplished by radiologists and pathologists in 68 of 71 cases when using the tissue trays compared with 292 of 369 without tissue trays. Confirmation of microcalcifications was accomplished after deeper sectioning into tissue blocks from discordant cases. In conclusion, a systematic approach is recommended to standardize reporting of calcifications. The use of Path/Rad Tissue Trays has created a level of concordance between pathologists and radiologists that previously did no exist. It improved diagnostic reliability, encouraged communication between pathologists and radiologists, and minimized false diagnoses and/or delays in cancer diagnosis.

Update on percutaneous needle biopsy of nonmalignant breast lesions

Certain nonmalignant lesions encountered on percutaneous breast biopsies pose dilemmas with regard to the most appropriate clinical management subsequent to needle biopsy (ie, surgical excision vs. follow-up). These lesions include columnar cell lesions, atypical ductal hyperplasia, lobular neoplasia, papillary lesions, radial scars, fibroepithelial lesions, and mucocele-like lesions. As minimally invasive diagnostic procedures are now standard it is more important than ever to be aware of the limitations of percutaneous biopsy, particularly with regard to apparently benign lesions because of the risk that the radiologically detected lesion may harbor malignant disease not represented in the biopsy specimen. This underscores the importance of radiologic-pathologic correlation. Increasingly, radiologists are adopting vacuum-assisted devices using larger gauge needles. The changing practices among radiologists are reflected in recent studies which have enriched the literature. In addition, magnetic resonance imaging is being used more frequently in breast imaging, resulting in pathologists more often encountering benign biopsies with uncertain imaging correlation. These changes prompted evaluation of the recent literature and its possible effect on management concerns. This review focuses on management issues following the diagnosis of nonmalignant lesions diagnosed on percutaneous breast biopsy and highlights imaging terms commonly used in breast radiology reports to facilitate accurate radiologic-pathologic correlation.

Segregation of radiographic calcifications in stereotactic core biopsies of breast: is it necessary?

Stereotactic-needle core biopsy (SNCB) is increasingly being used for the evaluation of mammographic calcifications. Radiography of SNCB specimens is essential to confirm the presence of calcifications within the biopsy material. To aid and direct the pathologist, it has been recommended that SNCBs be separated into those with and without radiographic calcifications and separately embedded. However, the utility of this separation to the pathologist has not been established. We reviewed 80 consecutive 11 gauge vacuum-assisted SNCB procedures performed for mammographic calcifications. The core biopsies were separated by the radiologist into those with and without radiographic calcifications ("calcs" and "no calcs"). Twenty-nine of 80 (36%) of the "calcs" cores were atypical or malignant, while 23 of 80 (29%) of the "no calcs" cores were atypical or malignant (chi(2) = 0.63, p = NS). The same diagnosis was rendered in the "calcs" and "no calcs" specimens in 61/80 cases (76%). Two cases of ductal carcinoma in situ, four cases of atypical ductal hyperplasia and 13 cases of fibroadenoma were diagnosed in the "calcs" cores only. However, in all cases where the pathologic lesion was seen in the "calcs" core only, the pathologic lesion was present on initial H&E levels and would have been diagnosed even in the absence of core segregation. Deeper sections were deemed necessary in seven of the 80 cases. No change in diagnosis was made on the basis of these deeper sections, even in the cases where histologic calcifications appeared on deeper sections. Separate embedding of SNCBs into those with and without radiographic calcifications does not appear to be of great utility to the pathologist. Equal attention should be given to all cores in the setting of SNCBs for mammographic calcifications.

Stereotactic breast biopsy: an audit of 18 months at BreastScreen Auckland

Stereotactic biopsy has become a widely used technique for marnmographically detected lesions that are clinically and sonographically occult. Vacuum-assisted (mammotome) biopsy on a dedicated prone stereotactic unit has further increased ease of biopsy and utility of the technique. Results of an 18-month audit in the national breast screening programme (BreastScreen Auckland and North) in the Auckland region demonstrates results comparable with those achieved elsewhere. Of a total of 399 stereotactic biopsies, 23 were excluded as they were 14-G core biopsies rather than 11-G mammotome biopsies. Of 376 mammotome biopsies, 10 (2%) failed, 266 (70.7%) were benign, 39 (10.3%) were atypical ductal hyperplasia (ADH) and 70 (18.6%) were malignant. Of these, 14.6% were ductal carcinoma in situ (DCIS) and 4% were invasive carcinomas. All cases diagnosed as ADH underwent formal excision biopsy. Of the 39 cases, 33 demonstrated benign disease or residual ADH only on excision (84.6%) and six (15.4%) patients were upgraded: five to DCIS and one to invasive carcinoma. The significant complication rate was 0.5%. Indications for biopsy were calcification in 89% of cases, mass lesions in 10.6% of cases and architectural distortion in 0.2% of cases. The failure rate of 2% compares with hookwire biopsy series. Practical issues and protocols have been presented.

[Stereotaxic breast biopsy techniques have become the standard of care for mammographically suspicious lesions]

An optimal technique for the evaluation of nonpalpable, suspicious mammographic lesions should have a low technical failure rate, no false-negative results and should remove the lesion completely. Since most of these lesions are benign, the procedure should be carried out in an outpatient setting without general anesthesia. Cancer is missed in 2.6% of cases with excisional biopsy following needle localization. Furthermore, 50-83% of these patients undergo a second surgical intervention for definitive surgical treatment. In contrast, the rate of missed cancers is less than 0.7% following stereotaxic core or large-core biopsies. However, using these techniques, discordant results and histologic high-risk lesions need to be recognized and reexcized. The cost-effectiveness of stereotaxic vacuum-assisted core biopsy has been demonstrated. Stereotaxic breast biopsy techniques such as vacuum-assisted core biopsy and large-core biopsy for suspicious mammographic lesions have low false-negative rates and result in few histologic underestimations.