Jones, Katie N.

98 Background: Concomitant with widespread adoption of axillary ultrasound (AUS) with ultrasound-guided needle biopsy (USNB) of suspicious lymph nodes (LN) for preoperative nodal staging of breast cancer patients, utilization of breast MRI, which includes axillary imaging, has increased. Little is known about the added value of MRI imaging of the axilla in this context. We undertook this study to assess the role of breast MRI in preoperative axillary nodal staging. Methods: We studied 988 consecutive invasive breast cancers in patients undergoing primary operation including axillary surgery, without neoadjuvant therapy, from 2010-2011. Results: 505 patients (51%) underwent MRI of which 168 (33%) demonstrated suspicious findings in the axilla. Abnormal axillary MRI findings included cortical thickening, edema, enhancement, hilar effacement, and/or altered shape and size. 114 patients had findings concordant with AUS. 54 patients had suspicious LNs on MRI either without a preceding AUS (33 cases) or after an initially negative AUS (21 cases). Second look AUS was performed in 29 of these cases and was abnormal in 3 (10%) in whom USNB confirmed metastatic adenopathy. Of the 54 cases with MRI-detected suspicious LNs 20 (37%) were node positive at operation with a pN stage of N0 (63%), N0i+ (5%), N1mic (4%), N1 (20%), N2 (6%), N3 (2%); extranodal extension was seen in 7 of 20 node-positive patients (35%). Conclusions: Second look AUS, when performed secondary to suspicious axillary MRI findings, identified LN metastasis preoperatively in 10% of patients. When MRI is done to evaluate the breast in newly diagnosed breast cancer patients, axillary findings can enhance the accuracy of preoperative nodal staging. We recommend second look AUS when MRI demonstrates suspicious axillary LN findings. [Table: see text]

49 Background: Predicting nodal positivity can guide surgical planning in breast cancer. Memorial Sloan-Kettering Cancer Center (MSKCC) and MD Anderson Cancer Center (MDACC) have established nomograms to predict sentinel node positivity. We propose that addition of distance of tumor from the nipple (DFN) can improve their performance. Methods: With IRB approval clinical T1/T2 tumors with pre-biopsy ultrasound were reviewed. MSKCC and MDACC nomogram predictions and the AUC-ROC were calculated. The addition of DFN was examined using multiple logistic regression and comparison of AUC-ROC values. Results: 401 breast cancers with clinical T1 (85%) or T2 (15%) tumors in 395 patients were included; of which 79/401 (19.7%) were node positive. Tumors were significantly closer to the nipple in those with positive nodes. 17/33 (51.5%) tumors within 2 cm of the nipple were node-positive versus 62/368 (16.8%) tumors > 2 cm from the nipple (p<0.0001). The MSKCC and MDACC nomograms each demonstrated good discrimination between node positive and negative patients with AUC-ROC values of 0.71 (95% CI: 0.64-0.77) and 0.74 (95% CI: 0.68-0.81), respectively. When added to the MSKCC nomogram, DFN ≤2 cm contributed significantly (OR 4.78, p=0.0001) to prediction of node positivity and improved the AUC-ROC to 0.73 (95% CI: 0.67-0.80). Similarly, DFN ≤2 cm was significant (OR 4.73, p=0.0002) when added to the MDACC nomogram and improved the AUC to 0.76 (95% CI: 0.70-0.82). Within nomogram probability categories, the proportion with positive nodes was consistently higher with DFN ≤2 cm. Conclusions: Tumor distance from nipple is associated with nodal positivity. When added to nomograms it improves prediction of node positivity. DFN should be considered when considering likelihood of nodal positivity for treatment planning. [Table: see text]

Abstract INTRODUCTION Next generation sequencing (NGS) of patients has significantly changed our ways to study cancer genomics as it provides precise estimates of gene expression, fusion transcripts, expressed single nucleotide variants (eSNVs), splice variants and copy number variants. The Breast Cancer Genome Guided Therapy (BEAUTY) is an ongoing clinical study in which RNA sequencing (RNAseq) and whole exome sequencing (WES) are performed prior to, during and after neoadjuvant chemotherapy. Here we report the use of these sequencing technologies to investigate gene expression levels and mutational profiles in a triple negative breast cancer (TNBC) patient enrolled in BEAUTY whose disease did not respond to neoadjuvant paclitaxel and anthracycline/cycphosphamide. METHODS Computational approaches were used to integrate WES and RNAseq data obtained before therapy (V1T), after 12 weekly paclitaxel treatments (V2T) and after anthracycline-based regimen at surgical resection (V3T) to study a single patient with persistent TNBC disease after neoadjuvant chemotherapy. RESULTS Using RNA-Seq data, we identified an inter-chromosomal fusion transcript between chromosome 20 and 22 (GNAS-TTC38) that was highly expressed at V1T, V2T and V3T. We also identified intra-chromosomal fusion transcripts that were expressed at two time points, such as fusion transcript (KANSL1-ARL17A) on chromosome 17 for V1T and V2T and fusion transcript (RBM12B-LINC00535) on chromosome 8 for V2T and V3T time points. Several gene expression changes were also observed. Gene expression analysis of V1T, V2T and V3T tumors was performed. Differential temporal gene expression profiles of 9884 genes that were significant and varying at different time points were obtained for pathway analysis. Pathway analysis of 9884 genes identified up regulation and down regulation of several transcription factors with a fold change of 2x or more. When compared to blood, DNA tumor and RNA-Seq data, we identified 81 common somatic eSNVs that were expressed in both V1T and V2T time points and we are in the process of investigating V3T data. We found alterations of key transporter domains (CD225, Coatamer_beta_C, DUF2435, Dynamitin, EI24, GLTP, LMF1, Porin_3, V-ATPase_C) in our V1T and V2T SNV data. Similar to gene expression analysis, we are in the process of obtaining the list of mutations at various time points to identify driver and passenger mutation candidate genes for this specific TNBC patient. CONCLUSIONS Our initial time-series analysis of eSNV, fusion transcripts and gene expression data demonstrate that intensive analysis for individual patients is feasible. Further investigation of drug transporters and transcription regulators may help develop personalized treatment strategies for patients with disease resistant to current regimens. Citation Format: Krishna R. Kalari, Xiaojia Tang, Kevin J. Thompson, Douglas W. Mahoney, Poulami Barman, Jason P. Sinnwell, Hugues Sicotte, Peter Vedell, Steven N. Hart, Travis J. Dockter, Katie N. Jones, Amy L. Conners, Ann M. Moyer, Daniel W. Visscher, Jia Yu, Bowen Gao, Sarah A. McLaughlin, John A. Copland, Alvaro Moreno-Aspitia, Donald W. Northfelt, Richard J. Gray, Vera J. Suman, Jeanette E. Eckel Passow, Jean-Pierre A. Kocher, Eric D. Wieben, Gianrico Farrugia, Cloann G. Schultz, James N. Ingle, Richard Weinshilboum, Matthew P. Goetz, Liewei Wang, Judy C. Boughey. Analysis of sequencing data to identify potential drug targets for an individual newly diagnosed with basal breast cancer who failed to respond to current standard neoadjuvant chemotherapy. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4185. doi:10.1158/1538-7445.AM2014-4185

Abstract INTRODUCTION Patient derived xenografts (PDX) may better reflect individual patient (pt) tumor biology; however, the feasibility of collecting PDX from percutaneous tumor biopsies (PTB) in the neoadjuvant setting is unknown. Furthermore, drug response phenotypes observed in PDX have not been prospectively compared to the corresponding pt clinical outcomes. METHODS The Breast Cancer Genome Guided Therapy Study (BEAUTY) is a prospective Mayo study of pts with high-risk breast cancer treated with neoadjuvant weekly paclitaxel (T) +/- trastuzumab followed by anthracycline based chemotherapy. PTB (at baseline) and residual surgical tissue (after all chemotherapy) are obtained for next generation sequencing (NGS) and PDX. Tumor biopsies (1-2 cores from 14 gauge needle) were implanted with Matrigel &lt;1 hour of collection in the flanks of NOD-SCID or NSG mice. Low dose estradiol was supplemented in the drinking water. Primary outgrowth rate was defined as PDX tumor volume &gt;50 mm3. Take rate was defined as development of at least 1 stably transplantable xenograft line/pt. To determine whether clinical T response assessed by MRI corresponded with in vivo T response, pretreatment PDX from 5 pts were injected into NOD-SCID mice (20 mice per pt PDX) and when tumors reached 100-200mm3, mice were randomized to no treatment vs T (20 mg/kg, ip. every 3-4 days). Two of these 5 patients had a MRI response defined as &gt;30% decrease in longest lesion. RESULTS Pretreatment PTB from 81 unique pts were implanted in 251 mice (2-4 mice/pt). PDX outgrowth rates were 33.3% (27/81 pts) and 22 stable PDX were established (overall take rate 27.2%). Take rates were as follows: triple negative breast cancer (46%; 13/28); HER2 (27%; 6/22), Luminal B (13%; 3/22), and luminal A (0%; 0/9). Residual surgical tumor (after all treatment) from 17 pts was injected into 85 mice (average 5 mice/pt) and the initial outgrowth rate was 23% (4/17) with 3 stably transplantable lines established. PDX, derived from pretreatment PTB of 5 pts (2 responders and 3 non-responders), were assessed for in vivo T response. The size of the T treated group was significantly smaller than the no treatment group for the PDX derived from the 2 clinical responders, with complete disappearance of tumor by 18 days. In contrast, the PDX derived from the 3 clinical non-responders had no evidence for T response. CONCLUSIONS We have demonstrated the feasibility of using PTB to establish PDX in a prospective neoadjuvant clinical study and have demonstrated similar T drug response phenotypes in in the PDX as seen in the corresponding pt. These data suggest that PDX generated prospectively may be useful for biomarker validation and the development and individualization of new drug therapy. Funded by the Mayo Clinic Center for Individualized Medicine and the Mayo Clinic Cancer Center Citation Format: Jia Yu, Ping Yin, Bowen Gao, Jason P. Sinnwell, Ann M. Moyer, Daniel W. Visscher, Amy L. Conners, Travis J. Dockter, Krishna R. Kalari, Xiaojia Tang, Kevin J. Thompson, Hugues Sicotte, Douglas W. Mahoney, Steven N. Hart, Peter T. Vedell, Poulami Barman, Katie N. Jones, Sarah A. McLaughlin, John A. Copland, Alvaro Moreno Aspitia, Donald W. Northfelt, Richard J. Gray, Vera J. Suman, Jeanette E. Eckel Passow, Eric D. Wieben, James N. Ingle, Zhenkun Lou, Gianrico Farrugia, Richard Weinshilboum, Matthew P. Goetz, Judy C. Boughey, Liewei Wang. Feasibility of using percutaneous tumor biopsies from a prospective neoadjuvant breast cancer study to develop patient derived xenografts and assess in vivo chemotherapy sensitivity. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1195. doi:10.1158/1538-7445.AM2014-1195