AB057. 190. Management and follow-up of atypical breast biopsies in a single institution

Background: Atypical hyperplasia encompassing both atypical ductal hyperplasia (ADH) and atypical lobular hyperplasia (ALH) identified on breast biopsy is identified as a benign entity that confers an increased lifetime risk factor for development of breast cancer. The aim of this study is to review the management and follow-up of patients diagnosed with ADH and ALH in our institution.

Methods: All breast biopsy specimens with ADH and ALH from January 2002 to September 2007 were identified from the histopathology database. Medical records, clinic letters, imaging and histopathology reports were reviewed up to 10 years from diagnosis to determine follow-up and cancer incidence in these patients.

Results: After exclusion of cases with accompanying carcinoma in situ (CIS) or invasive carcinoma on core biopsy, 64 patients with ADH/ALH were identified and reviewed. Subsequent excisional biopsy revealed CIS in 13 patients (20%), invasive carcinoma in 4 patients (6%) patients and benign pathology associated with atypical hyperplasia in 47 (73%) patients. Of the 47 patients with ADH/ALH who were assessed at follow up (median 90 months; range, 20–165 months), 2 (8%) patients developed invasive breast carcinoma, one at year 2 and one at year 6.

Conclusions: In keeping with international cohort studies, the inherent future cancer risk in patients with atypical hyperplasia extends beyond the medium term emphasizing the need for a longer term surveillance program beyond 5 years and allowing access to developments in risk reduction strategies.

Keywords: Atypical ductal hyperplasia; atypical lobular hyperplasia; core needle biopsy; excisional biopsy; cancer risk