Hines, SL

Abstract Abstract #4020 Background: HER2 positive (HER2+) breast cancer accounts for 20% of all breast cancer and is an independent adverse prognostic factor. Breast magnetic resonance imaging (MRI) has been shown to identify additional mammographically occult ipsilateral (I/L) and contralateral (C/L) disease, however indications for preoperative MRI in patients with newly diagnosed breast cancer are not standardized. While invasive lobular cancer, younger patient age, and increased breast density have been suggested as routine indications, the role of preoperative MRI according to HER2 status has not been evaluated.
 Methods: All patients with invasive breast cancer who underwent preoperative MRI between January 2003 and December 2007 were reviewed. Retrospective chart review was performed to collect clinical, radiographic, and pathologic data. The incidence of additional I/L or C/L malignacy was calculated. Additionally, changes in surgical management because of MRI findings were recorded.
 Results: Of the 401 women with invasive breast cancer undergoing preoperative breast MRI, 51 (13%) had HER2+ tumors. The average age at the time of MRI was similar in both groups. HER2+ patients were more likely to have nodal disease, and tumors with higher rates of lymphovascular invasion or extensive intraductal components.
 
 When compared to HER2- patients, more HER2+ patients had additional ipsilateral MRI abnormalities. A second ipsilateral cancer was found in 31% of HER2+ patients compared to 25% of HER2- patients. When analyzed according to ER status, HER2+/ ER- patients were more likely to have an additional site of cancer compared to HER2+/ER+ patients (42% vs 23%). Conversely, among HER2- patients, rates of additional ipsilateral cancer were similar for HER2-/ER+ (26%) and HERr2-/ER- (23%) patients. Of the 216 patients (HER2+ and HER2-) with additional ipsilateral MRI findings (benign or malignant), 125/216 (58%) patients were deemed appropriate breast conservation (BCT) candidates after MRI. However, BCT was only chosen in 84/125 (67%) patients. Additional contralateral disease was documented in 8% of HER2+ versus 5% of HER2- patients.
 Conclusions: HER2 positivity remains and important prognostic factor for women with breast cancer. Indications for routine preoperative MRI are unclear. In patients with newly diagnosed Her2+ invasive breast cancer routine preoperative MRI may be valuable in the subset of patients who are also ER-. Further study is needed to determine the influence of MRI on patient decisions for surgical therapy. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4020.

Abstract Abstract #4014 Background
 Preoperative magnetic resonance imaging (MRI) of the breasts in women with breast cancer (BC) has improved the detection of occult ipsilateral (I/L) and contralateral (C/L) malignancies. Breast MRI findings in patients with estrogen receptor (ER), progesterone receptor (PR), and HER2 negative (triple negative (TN)) disease have not been previously reported. Women with TN BC are at increased risk of distant metastases and a reduced survival vs. BC patients as a whole. One potential explanation may be the presence of occult disease. The role of bilateral breast MRI in these patients remains to be determined.
 Hypothesis
 Patients with TN BC are more likely to have occult malignancy identified by preoperative MRI vs. those with non-TN BC.
 Methods
 All newly diagnosed BC patients from 2003-2007 were reviewed. Information on age, race, histology, ER, PR, HER2, staging, treatment, MRI findings, subsequent investigations, and additional cancer diagnoses was recorded. The incidence of additional I/L or C/L malignany was calculated. The percentage of total patients initially felt to be candidates for partial breast irradiation who required a change in their cancer management was calculated.
 Results
 55 (11%) were diagnosed with TN BC, of whom 52 women completed preoperative MRI. 456 (89%) had non-TN BC; 421 completed preoperative MRI. The median age among TN and non-TN patients was 62 years (Table 1). A majority of women in both groups were Caucasian. African-American women were more likely to be diagnosed with TN vs. non-TN disease (11% vs. 6%).
 
 I/L BC was documented in 13/52 (25%) of TN patients vs. 25% of non-TN patients. No C/L cancers were detected in the TN group (6% in the non-TN group). Of the TN group, 15 patients required a change in their treatment (29%) based on findings from MRI vs. 32% of non-TN patients.
 Conclusions
 Patients with a new diagnosis of TN BC are not at increased risk of occult malignancy than those with non-TN BC. 25% of patients with TN BC had additional I/L disease not previously detected on clinical examination, mammogram, or ultrasound. Of those with non-TN BC, 25% were diagnosed with an additional I/L and 6% with C/L malignancy. The benefit of MRI was limited by false positives, with a number of patients in both groups undergoing a benign biopsy.
 These results suggest that patients with TN BC are not more likely than those with non-TN disease to have additional occult I/L or C/L cancer. The incidence of additional disease remains high and preoperative MRI may be beneficial. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4014.