Outcomes of patients with lobular in situ neoplasia of the breast: the role of vacuum-assisted biopsy.

OBJECTIVES: To audit the outcomes of patients with non-pleomorphic lobular in situ neoplasia (LISN) of the breast and clarify the role of vacuum-assisted biopsy (VAB), surgical biopsy and conservative management for this condition. MATERIALS AND METHOD: A single-centre retrospective review of hospital databases covering a 14-year period was performed. Patients with LISN as the most pertinent diagnosis on core needle biopsy (CNB), vacuum-assisted biopsy (VABs) or surgical biopsy were identified. The radiological features, histopathological findings and outcome of subsequent annual mammography were recorded. RESULTS: Between 1998 and 2012 there were 70 patients with LISN as the most pertinent diagnosis at CNB, VAB or surgery. 52 underwent VAB, typically 18 11-gauge samples. The pathology was upgraded from the preceding 14-gauge CNB in 7 cases. Of 11 patients who underwent surgery after VAB, one (who had undergone a low tissue yield VAB) was upgraded. There were no new breast cancers during a mean annual mammographic follow-up period of 53 months in 40 patients who had VAB with complete radiological-histopathological concordance. CONCLUSION: Provided there is adequate tissue sampling and radiological-pathological concordance, VAB is a safe alternative to open biopsy in the management of non-pleomorphic LISN.