Influence of complete lesion removal at VAB on the upgrade of B3 lesions presenting as microcalcifications: five years of experience from a referral centre
Author Block: G. Irmici1, C. Depretto1, L. Rabiolo2, G. Della Pepa1, E. D’Ascoli1, C. De Berardinis1, S. Schiaffino3, A. Cozzi3, G. P. Scaperrotta1; 1Milan/IT, 2Palermo/IT, 3Lugano/CH
Purpose: B3 breast lesions have uncertain malignant potential, with different risks of upgrade to malignancy at surgery and/or follow-up. This study on B3 lesions presenting as microcalcifications, for which vacuum-assisted biopsy (VAB) represents the standard approach, aimed to investigate the influence of complete or partial lesion removal at VAB on the subsequent upgrade rate (UR).
Methods or Background: For this retrospective monocentric study conducted in a referral centre, we retrieved 165 lesions presenting solely as microcalcifications and being categorised as BI-RADS 4/5 at mammography, then subsequently diagnosed as B3 at VAB (40 ADH, 53 FEA, 40 ALH, 18 PL, and 14 RS) between January 2016 and December 2020. Surgical pathology or at least 3-years follow-up were obtained to determine eventual lesion upgrade to malignancy. The χ², Fisher’s, and Mantel-Haenszel tests were performed to assess if complete lesion removal influenced URs, overall and among different B3 subtypes.
Results or Findings: Complete lesion removal was achieved in 99/165 (60.0%) cases. The rate of complete removal did not significantly differ among B3 subtypes (p=0.092, Bonferroni-adjusted multiple comparisons p≥0.101), ranging from 33.3% of PL (6/18) to 78.6% (11/14) of RS.
The overall UR was 8.5% (95% CI 5.1–13.7%, 14/165), not significantly differing among B3 subtypes (p=0.562).
Conversely, the UR of completely removed lesions (4.0%, 95% CI 1.6–9.9%) was significantly lower than that of partially removed lesions (15.2%, 95% CI 8.4–25.7%, p=0.020).
At stratified analysis according to B3 subtypes, the risk ratio of upgrade among completely and partially removed FEA (0.15, 95% CI 0.01–1.26) was significantly lower (Mantel-Haenszel test p=0.034) than those of ADH (0.36, 95% CI 0.07–1.90) and of ALH (0.74, 95% CI 0.05–10.99).
Conclusion: The UR of B3 lesions is significantly influenced by complete lesion removal, both overall and among different B3 subtypes.
Limitations: The relatively small sample size was an identified limitation.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Not applicable
Ethics committee - additional information: No additional information provided by the submitter.