Histopathologic Findings in Prophylactic Mastectomy Specimens: Experience of a Single Institution.
Irene A Czyszczon, Sunati Sahoo. University of Louisville, KY
Background: Recently, the rate of prophylactic mastectomy (PM) has been increasing to reduce the risk of developing breast carcinoma. However, it is controversial whether CPM benefits most women who are diagnosed with breast carcinoma. The objective of this study was to identify the frequency of malignant findings in PM specimens and identify pathologic factors that can predict involvement of PM specimens.
Design: A retrospective review of all prophylactic mastectomies between January 2004 and August 2010 was performed. The stage of tumor on the disease side and the pathologic findings in the prophylactic breast were analyzed.
Results: Between January 2004 and August 2010, 1469 women were newly diagnosed with breast cancer at our institution. 200 PM were performed on 185 patients during the following years: 2004, 4/223 (1.8%); 2005, 18/220 (8.2%); 2006, 16/206 (7.8%); 2007, 34/181 (18.8%); 2008, 43/209 (20.6%); 2009, 51/269 (19.0%); 2010 (as of August), 34/161 (21.1%). Of 185 patients, 170 underwent CPM for ipsilateral invasive carcinoma (136 patients) and DCIS (33 patients). 27 patients were treated with neoadjuvant chemotherapy. Tumor stage for ipsilateral carcinoma is as follows: Tis, 10%; T1, 53%; T2, 30%; T3, 4.9%; T4, 1.4%. Forty-nine of 138 (36%) patients had ipsilateral lymph node involvement. 15 patients had BPM for BRCA mutation, strong family history, or LCIS. 15 of 170 (8.8%) CPM specimens revealed occult carcinoma: 7 invasive and 8 DCIS. The index carcinoma in all 15 patients was infiltrating ductal carcinoma; 4 had locally advanced disease, 1 had multifocal disease, and the remaining 10 had node-negative T1 or T2 tumors. Prophylactic SLNB was performed in 158/200 PM (79%) cases; only 2 patients had nodal involvement, which originated from the index carcinoma.
Conclusions: The rate of PM has dramatically increased at our institution over the past 6 years. Occult carcinoma (DCIS and invasive) is not uncommon in CPM specimens. One-third of our patients with occult carcinoma had locally advanced or multifocal disease. Although it has been reported that CPM is more likely to harbor occult carcinoma in patients with invasive lobular carcinoma, none of our cases were of lobular histology. None of the BPM specimens had malignant lesions.
Monday, February 28, 2011 9:30 AM
Poster Session I Stowell-Orbison/Surgical Pathology/Autopsy Awards Poster Session # 15, Monday Morning