The positive predictive value of vacuum assisted biopsy (VAB) in predicting final histological diagnosis for breast lesions of uncertain malignancy (B3 lesions): A systematic review & meta-analysis

INTRODUCTION

High-risk or B3 breast lesions are considered lesions of uncertain malignant potential and comprise between 5 and 12% of initial biopsy results. We sought to perform a systematic review and meta-analysis of studies published within the last twenty years to determine the pooled Positive Predictive Value (PPV) of VAB in selected B3 lesions.

METHODS

The study report is based on the guidelines of PRISMA and Meta-Analysis of Observational Studies in Epidemiology.

OUTCOMES

The primary outcome of this study was to determine the PPV of VAB in determining final histological diagnosis in B3 breast lesions using pooled estimates. The secondary outcomes were to determine if needle gauge or the re-classification of Lobular Carcinoma in Situ(LCIS) introduced in 2012 influenced pooled estimates.

RESULTS

78 studies incorporating 6,377 B3 lesions were included in this review, 1214 of which were upgraded to DCIS or invasive malignancy following surgical excision(19%). The pooled PPV of VAB in Atypical Ductal Hyperplasia(ADH) and Lobular Neoplasia(LN) were 0.79(CI 0.76-0.83) and 0.84(CI 0.8-0.88). VAB of Flat Epithelial Atypia(FEA), radial scar and papillary lesions with/without atypia all had a pooled PPV >90% (underestimation rates 7%, 1%, 5% and 3% respectively). Needle gauge size and the change in LCIS classification did not appear to influence underestimation rates on subgroup analysis.

CONCLUSION

Results from this meta-analysis suggests it is reasonable to perform VAB as definitive treatment for certain B3 lesions, specifically LN, FEA, radial scar, and papillary lesions when specific criteria are fulfilled. Surgical excision should continue as the mainstay of treatment for ADH.

Calcifications with suspicious morphology at mammography: should they all be considered with the same clinical significance?

OBJECTIVES

To evaluate the positive predictive values (PPVs) of calcifications with suspicious morphology by incorporating distribution and clinical factors in two separate cohorts to provide more practical guidance for management.

METHODS

This retrospective study included 1076 consecutive women from two cohorts (cohort A, 556; cohort B, 520), with calcifications of suspicious morphology seen on mammography that were pathologically confirmed or followed with mammography. Reader-averaged PPVs of the calcifications were analyzed and compared by logistic regression using the generalized estimating equation. Multivariate logistic regression analysis was performed to evaluate independent factors associated with the PPVs of suspicious calcifications.

RESULTS

Overall reader-averaged PPVs of suspicious calcifications were 16.8% and 15.2% in cohort A and B, respectively. Reader-averaged PPVs according to morphology in cohort A and B were as follows: amorphous 9.1%, 6.4%; coarse heterogeneous 16.1%, 22.1%; fine pleomorphic 78.8%, 44.7%; and fine linear branching 78.6%, 85.1%, respectively (p < 0.001). PPVs for diffuse amorphous combinations were 2.6% and 2.6%, and for regional amorphous calcifications, 3.6% and 3.1%, respectively. Among diffuse amorphous calcifications, the PPVs for women ≥ 50 years and women without a personal history of breast cancer ranged from 0.0 to 1.9%.

CONCLUSIONS

Amorphous calcifications have lower reader-averaged PPVs compared to calcifications with other suspicious morphology, falling into the BI-RADS 4a assessment (PPV 2-10%). Amorphous calcifications with diffuse distributions detected in women > 50 years old and without a personal history of breast cancer have reader-averaged PPVs < 2.0%. Further prospective studies are necessary to confirm if these patients can be managed with imaging follow-up.

KEY POINTS

• In two cohorts, reader-averaged positive predictive values (PPVs) for suspicious calcifications showed lower rates for amorphous calcifications. • In two separate cohorts, reader-averaged PPVs showed lower rates for diffuse amorphous calcifications, falling into the BI-RADS 4a assessment category (PPV 2-10%). • Diffuse amorphous calcifications detected in women > 50 years old and without a personal history of breast cancer have reader-averaged PPVs < 2.0%.

B3-lesions of the breast and cancer risk - an analysis of mammography screening patients

The use of mammography screening, followed by needle core biopsy (NCB), is associated with an increasing amount of invasive procedures. A considerable amount of specimens must be classified as lesions with uncertain malignant potential (B3-lesion). In these cases, an open biopsy is indicated for further diagnosis. We evaluated patients with B3-lesions to determine the risk of malignancy corresponding to the histopathological NCB results and the type of radiological lesion identified. A total of 95 patients participating in the German mammography screening program with a B3-lesion following NCB (104 B3-lesions in total) were included in our analysis. We analyzed the correlation between the initial histopathological findings from the NCB specimen and cancer risk. We further analyzed the correlations of malignant results with the type of mammographic lesion. In 23 cases (22%), histopathological examination following excision revealed a malignant lesion, including invasive and in situ carcinoma. The positive predictive value of the subgroups of B3-lesions ranged between 0.11 and 0.31; the B3-lesion associated with the highest cancer risk was the atypical ductal hyperplasia; however, no significant difference was observed between the B3-lesion subgroups (P=0.309) regarding the risk of malignancy. Comparing the different types of mammographic findings, such as radiological mass or microcalcifications, there was no significant difference in the risk for malignancy (P=0.379). The different types of B3-lesions did not exhibit differences in the risk for malignancy, and the morphological type of mammographic lesion does not appear to be correlated with cancer risk; therefore, our results underline the need for open biopsy in patients with B3-lesions following NCB.

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.

Role of Breast Imaging in Predicting Outcome of Lesions of Uncertain Malignant Potential (B3) Diagnosed at Core Needle Biopsy

Aims

To elucidate whether breast imaging can predict final histologic diagnosis of lesions of uncertain malignant potential diagnosed at ultrasound core needle biopsy (CNB).

Methods

The imaging characteristics (mammography, ultrasound, and magnetic resonance imaging [MRI]) of lesions of uncertain malignant potential in the breast that were obtained by ultrasound CNB were retrospectively analyzed in 87 women. Radiologic characteristics of lesions were compared to definitive histopathologic findings.

Results

Out of 87 breast lesions of uncertain malignant potential, 27 (31%) were diagnosed as papillary lesions, 24 (28%) atypical ductal hyperplasia, 19 (22%) lobular intraepithelial neoplasia, 9 (10%) phyllodes tumors, 3 (3%) radial sclerosing lesions, and 5 (6%) unspecified lesions of uncertain malignant potential. The underestimation rate of malignancy at CNB based on the total number of lesions on final follow-up was 22%. Using multivariate logistic regression, Breast Imaging-Reporting and Data System (BI-RADS) score (odds ratio [OR] = 12.29, p = 0.027) and Göttingen MRI scoring system (OR = 8.1, p = 0.008) were found to be independent predictors of malignancy. Receiver operating characteristic analysis showed that Göttingen MRI score >3 provides a plausibly good cutoff value with sensitivity of 100 (95% confidence interval [CI] 74%-100%) and specificity of 76% (95% CI 61%-88%).

Conclusions

Lesions of uncertain malignant potential classified as BI-RADS 5 and Göttingen score 4 or higher are at significantly higher risk of harboring malignancy and therefore should be recommended for surgical excision.

Mammotome(®) and EnCor (®): comparison of two systems for stereotactic vacuum-assisted core biopsy in the characterisation of suspicious mammographic microcalcifications alone

PURPOSE

The authors sought to compare the diagnostic performance of the Mammotome(®) and EnCor(®) vacuum-assisted breast biopsy (VABB) systems in the assessment of suspicious mammographic microcalcifications.

MATERIALS AND METHODS

Between January 2011 and July 2012, a total of 169 VABB were performed by stereotactic guidance on a prone table. The Mammotome(®) 11G (S1) or EnCor(®) 10G (S2) probes were used randomly. Sampling time and the number of frustules collected were considered; sensitivity, specificity, diagnostic accuracy, positive and negative predictive value (PPV, NPV) of both procedures were evaluated, considering the final histological examination as reference (B1, B3, B5 lesions underwent surgical excision; B2 lesion were considered confirmed after a negative follow-up of at least 1 year).

RESULTS

There were no statistically significant differences between the two groups of patients according to the number of procedures (S1 82/169; S2 87/169), average age, BIRADS category (4a, b), and average size of the lesions. The two systems did not differ statistically for correlation with the final histology (S1 k = 0.94 ± 0.06; S2 k = 0.92 ± 0.08) and underestimation of B3 lesions or in situ (S1 4.5%; S2 4.3%). Sensitivity, specificity, PPV, NPV, diagnostic accuracy of S1 and S2 were also not statistically different. The systems differed only in sampling time (S1 80; S2 63 s), but not in total procedure time.

CONCLUSIONS

Our study confirms the effectiveness of VABB in the assessment of microcalcifications and highlights the lack of significant differences between the two systems in terms of diagnostic performance.