Triaging Atypical Lobular Hyperplasia and Lobular Carcinoma In Situ on Percutaneous Core Biopsy to Surgery or Observation: Assiduous Radiologic-Pathologic Correlation Works, Quantitating Extent of Disease Does Not

Abstract

Context.— The management of lobular neoplasia (LN) found on core biopsy is controversial and ranges from obligatory surgical excision to clinical/imaging observation. Objective.— To determine if in cases of core needle biopsy yielding LN, quantification of normal and diseased terminal ductal lobular units (TDLUs) can predict which cases require surgical excision and which can be safely followed. A secondary goal is to assess whether the concordance or discordance of core biopsy results, determined by rigorous radiologic-pathologic correlation, can predict for upgrade to malignancy at excision. Design.— In this retrospective study, 79 specimens from 78 women who underwent image-guided core needle biopsies between 2005 and 2012 yielding LN were evaluated for total number of TDLUs and total number and percentage of TDLUs involved by LN. Additionally, radiologic-pathologic correlation was performed to assess concordance or discordance. All were correlated with the results of surgical excisional biopsy or imaging/clinical follow-up. Results.— There were 5 upgrades to malignancy. There was no association between upgrade to malignancy and any of the 3 TDLU variables evaluated, including total TDLUs in the specimen (P = .42), total abnormal TDLUs (P = .56), and percent of TDLUs that are abnormal (P = .07). Kendall rank correlation demonstrated a correlation between discordance and upgrade to cancer at surgery that was statistically significant (τb = −0.394, P < .001). Conclusions.— Quantifying total TDLU and those involved by LN on core biopsy will not aid in triaging patients to surgery or observation. Assiduous radiologic-pathologic correlation to determine lesion concordance/discordance can predict those patients who would benefit from surgical excision.