The impact of a Breast Center Revision of the Histopathological Diagnosis of Breast Lesions After an External Core Needle Biopsy.

Abstract

Background - As a widely implemented practice, pathologists at high-volume Breast Centers often review all externally performed breast tumor biopsies, coming from low-volume private or public institutions. This study aims to assess the impact of these revisions on the occurrence of discrepancies, regarding treatment pathways or options. Methods - We retrospectively selected 469 patients who were referred to the Breast Center of Unidade Local de Saúde de São João, Porto, Portugal, from July 1st, 2018 to June 30th, 2023. Changes in histological classification, tumor type, tumor grade, immunohistochemical profile, presence of DCIS, lymphovascular invasion (LVI), Ki67% or molecular classification were evaluated. These discrepancies were classified as minor or major, depending on their impact on clinical attitude. Results - Among the 18 variables analyzed, the vast majority showed substantial to almost perfect agreement. Discordant findings were observed in 272 cases (58.0%), with 85 (18.1%) classified as major discrepancies. Of the variables that resulted in lower agreement (tumor grade, DCIS component of invasive tumors and LVI), only tumor grade had potential impact on clinical management. The review process resulted in a median delay of 15 days in initiating the first treatment. Conclusions - Given the high rate of agreement across nearly all the analyzed variables, coupled with the low incidence of major changes, the associated costs of pathology revision and the treatment access delay attributed to this process, we can conclude that repeating the pathology assessment may be waived. Only in selected cases should the tumor grade be subject to reanalysis.