RESUMO
OBJECTIVE: Lobular intraepithelial neoplasia (LIN) diagnosed on image-guided biopsy may be associated with an undiagnosed cancer. This is called under-diagnosis. The consequence is that management of these lesions is often surgical. But many surgeries finally are unnecessary. The aim of our study was to define criteria to avoid unnecessary surgery. MATERIALS AND METHODS: This is a single-center, retrospective after a database collected prospectively study. Fourteen thousand biopsies were analyzed, including 456 diagnosed NLI. Under-diagnosis rates were analyzed according to many criteria. The average duration of following was 45 months. RESULTS: For atypical lobular hyperplasia (ALH), we obtained 7.6% under-diagnosis and combining several criteria, we got a low risk of cancer (2%). For LCIS, this rate was 23% and any low-risk group could be identified. CONCLUSION: ALH with calcifications≤20 mm, without any atypical lesion associated, histologically focal and whose removal is representative may be safely observed. For other LIN, surgery remains indicated.
