Background: Contemporary improved neoadjuvant systemic therapy (NST) for breast cancer may result in a pathologic complete response (pCR) in up to 60% of patients (pts) yet imaging alone has a poor negative predictive value to determine which pts might be spared surgery. This study was designed to evaluate the hypothesis that percutaneous image guided biopsy after NST can accurately identify patients who may forgo surgery. Methods: Prospective single-center IRB approved study of 34 pts with clinical T1-3 N0-3 triple-negative (TN, n=23) or HER2-positive (n=11) invasive ductal cancer who received standard NST and consented for ultrasound/mammography guided vacuum-assisted core biopsy (VACB) and fine-needle aspiration (FNA) biopsy prior to standard surgery. Main outcome measures included accuracy, false-negative rate (FNR), and negative predictive value of image guided biopsy in predicting residual disease after NST. Breast pCR was defined as no residual DCIS or invasive disease. Final biopsy showing atypia and/or suspicion of residual disease was recorded as positive. Results: Median initial maximum tumor size based on imaging and physical exam was 3 cm (1.2-7 cm) and 47.1% had FNA/core biopsy proved nodal metastases. Final median maximum residual tumor size after NST was 0.9 cm (0-4.2 cm) with 94.1% having no palpable abnormality. Median number of VACB (9G) removed following NST was 10 (4-14) and was performed by stereotactic (67.6%) or ultrasound (32.4%) guidance. Overall, a breast pCR occurred in 18 (52.9%) of pts and breast pathologic response was concordant with nodal pathologic response in 33 (97%) of pts (1 pt with a breast pCR had 1/15 nodes with metastases). Overall, VACB combined with FNA following NST had a 100% (95% CI 89.7-100) accuracy, 0% FNR (95% CI 0-20.6), and 100% (95% CI 81.5-100) negative predictive value for determination of residual breast disease. Grade 1 adverse events which resolved from biopsy (bleeding, hematoma, bruising) occurred in 6 pts (17.6%). Conclusions: High rates of pCR among pts with TN/HER2-positive breast cancer receiving NST occur in a significant proportion of pts. The use of image guided VACB/FNA can identify pts after NST where significant residual disease is unlikely. Based on these results, an IRB approved clinical trial will shortly commence for pts with T1-2 TN/HER2-positive breast cancer with documented image guided biopsy proved pCR after NST to be followed by standard definitive whole-breast radiotherapy without surgery.Background: Contemporary improved neoadjuvant systemic therapy (NST) for breast cancer may result in a pathologic complete response (pCR) in up to 60% of patients (pts) yet imaging alone has a poor negative predictive value to determine which pts might be spared surgery. This study was designed to evaluate the hypothesis that percutaneous image guided biopsy after NST can accurately identify patients who may forgo surgery. Methods: Prospective single-center IRB approved study of 34 pts with clinical T1-3 N0-3 triple-negative (TN, n=23) or HER2-positive (n=11) invasive ductal cancer who received standard NST and consented for ultrasound/mammography guided vacuum-assisted core biopsy (VACB) and fine-needle aspiration (FNA) biopsy prior to standard surgery. Main outcome measures included accuracy, false-negative rate (FNR), and negative predictive value of image guided biopsy in predicting residual disease after NST. Breast pCR was defined as no residual DCIS or invasive disease. Final biopsy showing atypia and/or suspicion of residual disease was recorded as positive. Results: Median initial maximum tumor size based on imaging and physical exam was 3 cm (1.2-7 cm) and 47.1% had FNA/core biopsy proved nodal metastases. Final median maximum residual tumor size after NST was 0.9 cm (0-4.2 cm) with 94.1% having no palpable abnormality. Median number of VACB (9G) removed following NST was 10 (4-14) and was performed by stereotactic (67.6%) or ultrasound (32.4%) guidance. Overall, a breast pCR occurred in 18 (52.9%) of pts and breast pathologic response was concordant with nodal pathologic response in 33 (97%) of pts (1 pt with a breast pCR had 1/15 nodes with metastases). Overall, VACB combined with FNA following NST had a 100% (95% CI 89.7-100) accuracy, 0% FNR (95% CI 0-20.6), and 100% (95% CI 81.5-100) negative predictive value for determination of residual breast disease. Grade 1 adverse events which resolved from biopsy (bleeding, hematoma, bruising) occurred in 6 pts (17.6%). Conclusions: High rates of pCR among pts with TN/HER2-positive breast cancer receiving NST occur in a significant proportion of pts. The use of image guided VACB/FNA can identify pts after NST where significant residual disease is unlikely. Based on these results, an IRB approved clinical trial will shortly commence for pts with T1-2 TN/HER2-positive breast cancer with documented image guided biopsy proved pCR after NST to be followed by standard definitive whole-breast radiotherapy without surgery. Citation Format: Kuerer HM, Rauch GM, Krishnamurthy S, Adrada BE, Caudle AS, DeSnyder SM, Santiago L, Lucci A, Hobbs BP, Gilcrease M, Hwang R, Candelaria RP, Chavez Mac-Gregor M, Arribas E, Moseley T, Teshome M, Miggins MV, Smith BD, Valero V, Hunt KK, Yang WT. Feasibility trial for identification of patients for eliminating breast cancer surgery following neoadjuvant systemic therapy [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-16-30.

Background: PI3K/Akt/mTOR signaling is being actively pursued as a therapeutic target. We sought to determine how tumor heterogeneity and biospecimen variables affect assessment of PI3K/Akt/mTOR pathway activation. Methods: Intraoperative image-guided core-needle biopsies (CNB) of primary breast tumors were prospectively collected in 53 patients with invasive breast cancer. After surgery, specimens were collected from the center and periphery of the excised tumor. CNB, central and peripheral surgical specimens were assessed with reverse phase proteomic arrays (RPPA), H&E and immunohistochemistry (IHC). Results: The expression of standard of care markers ER, PR, and HER2 by RPPA correlated well between biospecimen types. Overall, there was a significant correlation between the expression of 132 (86%) of 154 different markers in the center and periphery; the correlation was significantly higher for smaller tumors, and with shorter cold ischemia time. Expression of many investigational prognostic markers and druggable targets on CNB correlated with expression in the surgical specimen (average of center and periphery), while others, such as EGFR and c-MET, had a weak correlation. Of 154 RPPA markers, 132 (86%) were not statistically different between the center and periphery, and 97 (67%) were not different between the CNB and the surgical specimen. On analysis of the PI3K/AKT/mTOR pathway, pAkt S473 and PTEN had a significant correlation between central and peripheral specimens, and between CNB and surgical specimens. However, pAkt S473, pS6 S235/236 and pS6 240/244 levels were higher in CNB than the central specimens both by RPPA and by IHC. When patients were classified by RPPA PI3K pathway activation score, there was a moderate agreement between classification on the CNB and central specimens (Cohen's Kappa 0.539). However 9 of 20 tumors classified as having PI3K activation on CNB were classified as not having pathway activation on central specimens. Conclusions: There is remarkable homogeneity in expression of biomarkers within a tumor. However, proteomic markers are differentially expressed by biospecimen type and other preanalytic variables. PI3K pathway activation is greater in CNB compared to surgical samples. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P1-07-06.

Background: Image-guided percutaneous needle biopsy of the breast is a common procedure. In breast cancer patients (pts) undergoing core biopsies and surgical resection on the same day, the rate of tumor cell displacement along the needle track has been reported to be up to 50%. However, the clinical significance of this finding in triple negative breast cancer (TNBC) patients (pts) undergoing serial biopsies while receiving neoadjuvant chemotherapy (NACT) is unknown. Here we report the incidence of needle-track seeding (NTS) in a cohort of TNBC pts enrolled on a molecular triaging protocol involving serial biopsies of the index breast lesion. Methods: We reviewed the clinical records of 144 consecutive TNBC pts enrolled on a molecular triaging protocol at MD Anderson Cancer Center. Per protocol, all pts underwent a pre-treatment research biopsy and were initiated on anthracycline based NACT (AC). Pts with inadequate response to front-line NACT were encouraged to undergo additional biopsies of the index breast lesion prior to switching therapies. Serial breast ultrasound (US) was performed to monitor therapeutic response and incidental evidence of needle-track seeding noted on US was documented. Results: Clinicopathological characteristics of the pts are summarized in Table 1. 89% (128/144) of pts had a diagnostic breast biopsy done at another center prior to presenting at MDACC. To date, we have performed 209 US guided biopsies of index breast lesions in 144 pts. 92% (193/209) of these biopsies were done mainly for research purposes. 1.4% (2/144) of pts were found to have evidence of NTS on follow up US. The first pt had a T1N0 (1.9cm), grade 3, invasive ductal carcinoma (IDC) at diagnosis. She underwent a diagnostic biopsy followed by a research biopsy before initiating AC. She was found to have NTS as well as progression of disease (PD) on follow up US after 2 cycles of AC. The second pt had a T2N0 (3cm), grade 3 IDC at diagnosis. She underwent a diagnostic biopsy at another center, followed by a research biopsy before initiating AC. Like the first pt, she was found to have NTS and PD on follow up US after 2 cycles of AC. Both pts are currently on neoadjuvant clinical trials of novel agents. Conclusion: The rate of NTS detected on US in TNBC pts undergoing serial biopsies of index breast lesions while receiving NACT is low and further studies are needed to determine the impact of serial biopsies on long term outcomes in TNBC. Table 1: Patient CharacteristicsCharacteristicN=144Age - Median (years, interquartile range)55 (46-62)Tumor Size Mean (cm, standard deviation)3.4 (2.2)T1 – n(%)35 (24)T2 – n(%)89 (62)T3 – n(%)19 (13)T4 – n(%)1 (1)Clinical Nodal Status Negative – n(%)74 (51)Positive – n(%)70 (49)Grade 1 – n(%)1 (1)2 – n(%)17 (12)3 – n(%)124 (86)Unknown – n(%)2 (1)Histologic Subtype Invasive ductal carcinoma – n(%)121 (84)Invasive lobular carcinoma – n(%)2 (1)Mixed ductal and lobular carcinoma – n(%)3 (2)Metaplastic carcinoma – n(%)13 (9)Not specified – n(%)5 (3)Laterality Right – n(%)72 (50)Left – n(%)72 (50) Citation Format: Yam C, Santiago L, Candelaria RP, Adrada BE, Rauch GM, Hess KR, Litton JK, Piwnica-Worms H, Mittendorf EA, Ueno NT, Lim B, Murthy RK, Damodaran S, Helgason T, Huo L, Thompson AM, Gilcrease MZ, Symmans WF, Moulder SL, Yang W. Risk of needle-track seeding with serial ultrasound guided biopsies in triple negative breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-03-05.

Objectives: To evaluate associations between qualitative and quantitative MRI features and tumor infiltrating lymphocytes (TIL) levels in HER2+ subtype of breast cancer, as potential prognostic non-invasive imaging markers for treatment response prediction. Materials and Methods: Retrospective review of breast cancer patients who had MRI at staging, neoadjuvant chemotherapy and surgery from January 1, 2008 through December 31, 2015 was performed. BI-RADS lexicon was used for lesion evaluation. Demographic, imaging, and pathologic data including TIL levels were documented. Quantitative MRI texture analysis was performed using 3 types of textural features (TF): local binary patterns (LBP), gray-level co-occurrence matrix (GLCM), and threshold adjacency statistics (TAS). Associations between MRI quantitative TF, TIL levels, and pathologic complete response (pCR) were evaluated by Pearson correlation and logistic regression. Results: There were 50 HER2+ patients (median age 51 years, range 29-59) with pretreatment MRI and TIL status for analysis; 27 patients had pCR at surgery. Qualitative MRI analysis showed that mass rim-enhancement (p<0. 05) and fast early enhancement kinetics (p<0.01) were associated with higher TIL levels. No association between qualitative MRI features and pCR was found. Nine TF significantly correlated with pCR (p<0.05): angular 2nd moment (GLCM), 75 percentile (LBP), standard deviation (GLCM), adjacency 0-5 (TAS). This is indicative of association of tumor heterogeneity with pCR. Three TF were significantly associated with high TIL levels (p<0.05): standard deviation, adjacency 1 and 2. Additional four TF had high association with TIL (p<0.1): sum entropy, adjacency 0, 3 and 4. These findings showed that increased heterogeneity, complexity and entropy were associated with high TIL level. Three TF were significantly associated with both, pCR and TIL (p<0.05): 75 percentile, standard deviation, adjacency 8. Conclusion: Quantitative tumor texture analysis based on statistical modeling showed specific nine TF indicative of tumor heterogeneity associated with pCR; and seven TF indicative of increased heterogeneity, complexity, and entropy associated with high TIL levels in HER2+ breast cancer. Analysis of associations of MRI quantitative TF with pCR and TIL in HER2+ breast cancer may help to develop prognostic non-invasive imaging markers for treatment response prediction. Citation Format: Rauch GM, Zhu H, Li H, Adrada BE, Santiago L, Candelaria RP, Wang H, Leung J, Litton J, Wu Y, Murthy R, Mittendorf EA, Yang W. Association of quantitative MRI features with tumor infiltrating lymphocytes and treatment response prediction in HER2 positive subtype of breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr PD2-09.