bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract P1-01-12: A Novel Method for Sentinel Lymph Node Biopsy by Indocyanine Green Fluorescence Technique in Breast Cancer
Authors: Sugie T , Kassim KA , Takeuchi M , Hashimoto T , Yamagami K , Masai Y , Toi M.
Published: April 2011

Background: Sentinel lymph node (SLN) biopsy is the standard method to assess the actual axillary lymph node status in breast cancer. Currently dye techniques, radioisotope techniques or combined techniques are usually used for SLN detection. Recently, near infrared fluorescence imaging has been applied clinically in a breast cancer patient to identify SLN. In this study, the feasibility of SLN biopsy using the indocyanine green (ICG) technique were evaluated.

Methods: The study involved four hundreds eleven patients with clinically node negative early breast cancer who underwent SLN in three institutes. A combination of ICG as a fluorescence emitting source and blue dyes were injected in the subareolar area and lymphatic flows were traced with a charge coupled device camera and a real-time image guided surgery enabled to identify the fluorescence image of SLN after meticulous dissection.

Results: The subcutaneous lymphatic channels were detected precisely in all cases. The identification rate of SLN was 99%, (408/411) with a mean number of 2.3±1.2 (range, 1-9) nodes identified per patient. Only one SLN harvested in 30.1% of patients, two in 29.4%, three in 23.9% and four or more in 15.9% of patients. Thirty nine cases (9.5%) had SLNs involved and all of them were ICG positive and 30 of 39 patients (77%) had one SLN involved.

Conclusions: This ICG fluorescence method is simple and achieves a high SLN identification rate. This technique does not require a facility equipped to use radioisotopes. This means that SLN biopsies could even be performed in a small hospital. Orderly and sequential dissection along the lymphatic flow may provide higher sensitivity compared with the conventional radioisotope method. A direct comparison between the radioisotope and ICG fluorescence methods is now required.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-01-12.
Abstract P1-01-16: Evaluation of Sentinel Node Biopsy Using a Combined Dye and Fluorescence Method for Breast Cancer
Authors: Yamada A , Chishima T , Kimura M , Shimizu D , Hasegawa S , Ishikawa T , Endo I.
Published: April 2011

Background: Sentinel lymph node (SLN) dissection is now widely accepted for staging the axilla in patients with breast cancer. At present, several methods are used to detect SLN. A combination of blue dye and radioactive colloid has been described previously as a superior method for detecting SLN in breast cancer patients. However, use of radioactive colloids is not generally available for various reasons in Japan. SLN detection guided by indocyanine green (ICG) fluorescence could emerge as a new method for SLN biopsy. The aim of this study was to evaluate sentinel node biopsy using a combined dye and fluorescence method for breast cancer.

Methods: Fifty-eight patients with clinically node-negative breast cancer were examined between April 2008 and March 2009 at Yokohama City University Hospital. Intradermal injections of 20 mg/5 ml of indigo carmine and 0.5 mg/0.1 ml of ICG were made into the upper-lateral region of the periareolar area. Subcutaneus lymphatic channels draining from the areola to the axilla were visible under fluorescence within a few minutes. SLNs were then dissected under direct vision supported by fluorescence navigation. Palpable lymph nodes were also dissected. All SLNs were histologically evaluated by 2-mm serial section and staining with hematoxylin and eosin. Patients with positive SLNs underwent axillary lymph node dissection (ALND), while patients with negative SLN did not.

Results: SLNs were identified in 58 patients (100%). ICG fluorescence imaging was compared with indigo carmine dye, and SLNs were identified in 57 and 52 patients, respectively (detection rate: ICG, 98.3%; dye, 89.7%). The mean number of excised SLNs was 2.72. Mean numbers of lymph nodes showing fluorescence and blue stain from injected dye were 2.31 and 1.41, respectively. Eight of 58 patients (13.8%) had metastases detected in the SLN, so ALND were subsequently performed. Five of these cases were without metastases at non-SLN that were dissected. One patient showed metastasis in a SLN that was positive for fluorescence, but negative for blue dye. Among all cases, 1 patient (1.7%) showed an SLN without fluorescence or blue staining, and this case was detected by palpation only.

Conclusion: Combined use of dye and fluorescence method identified SLNs effectively.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-01-16.
Abstract P1-01-17: Comparative Analysis of Metastatic Tumor Cells within the Sentinel Lymph Nodes of Breast Cancer Patients Utilizing a Novel Approach
Authors: Zhang J , Liu Y , Ju J , Xu L.
Published: April 2011

Background and Objective: The intrinsic high false negative rate associated with intraoperative analysis of SLN may result in a second surgical procedure for the patient. We attempt to improve the intraoperative and the pathologic and molecular evaluation of SLN by utilizing novel immunobead methods for detection and assessment of tumor cell expression of Her2, CD44 and Muc1.

Methods: During the operation of breast cancer patients, gived sentinel lymph node biopsy firstly, and the SLN will each be divided in four quadrants, and two quadrants (B,C) will be brought to the pathologist for routine intraoperative analysis and further immunhistochemical (H&E and CK) examination often 2 mm thick sections of each quadrant.

The other (A,D) quadrants will be immediately mechanically disaggregated and filtered in order to remove stromal elements and cellular debris. The resulting cell suspension will be incubated with 4.5 µm magnetic beads coated with MOC31 antibody, and simultaneously with different nonmagnetic, fluorescent microparticles coated with either anti-Her2, anti-CD44, or anti-Muc1 by flow-cytometry.

Results: 62 cases from 2009.1 to 2009.9 in our hospital has been studied, and results as follows: 1. Immunomagnetic evaluation of alive tumor cells in SLNs is rapidly and easily performed using the MOC-31 antibody that binds to the vast majority of breast cancer cells. The novel technologies will demonstrate higher detection sensitivity (96%) and lower false negative rate (4.0%). 2. For the intraoperative frozen HE staining, the sensitivity was 68%, false negative rate was 32%; and for CK-IHC, the sensitivity was 76.0%, and the false negative rate was 24%. 3.To compare to standard intraoperative procedures and histopathologic techniques of analyzing the SLN to that of the novel approach, it could get higher sensitivity (96%vs 68%,P=0.023;96%vs76%,P=0.049), lower false negative rate (4%vs32% ,P=0.023;4%vs24%,P=0.049) and higher micrometastasis detection rate. 4.Expession of Her2,CD44 and Muc1 in SLN is 32.5%±2.2%,83.4± 4.1% and 86.6%±3.4%, and each has positively correlated with the expression of that in primary tumor (P<0.5).

Conclusion: Our novel approach that utilizing immunobead detection of metastatic breast cancer cells, and simultaneously characterize the isolated cells for membrane markers coated with antibodies targeting Her2, Muc1 or CD44 by flow-cytometry, has rapid speed and high accuracy. Compared to traditional HE and CK-IHC, it has higher sensitivity and lower false negative rate, and could be used more widely and easily. Expression of CD44, Her2 and Muc1 in sentinel lymph nodes were positively correlated with the expression of those in primary tumor. It is suggested that the three biomarkers above could predict metastasis of sentinel lymph nodes, and maybe direct treatment after operation.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-01-17.
Abstract P1-01-21: Predicting Risk of Axillary Lymph Node Metastasis: A Novel, Decision Tree-Based Approach That Can Handle Incomplete Datasets
Authors: Takada M , Sugimoto M , Naito Y , Kondo M , Kuroi K , Inamoto T , Tomita M , Toi M.
Published: April 2011

Background: Although axillary lymph node (AxLN) status, the most important prognostic factor in primary breast cancer patients, is used to tailor systemic therapy, precise staging of AxLN status before primary systemic therapy remains difficult. Sophisticated computational tools, especially nomograms, are used to predict the AxLN status. However, their prediction ability is limited by the requirement for datasets without any defects and their ability to deal with only a limited number of features. The aim of this study was to develop a novel mathematical algorithm to predict the AxLN status that can handle datasets with a large number of features containing missing values as are frequently observed in clinical datasets.

Methods: Pathological-, physical-, and diagnostic-image features (mammography and ultrasonography) from patients with primary invasive breast cancer who initially underwent sentinel lymph node biopsy or had undergone axillary lymph node dissection were used for training (n=168). Data resampling, feature-selection based on a support vector machine, an alternative decision tree (ADTree), and data ensemble methods were integrated to predict AxLN metastasis from the large number of clinicopathological variables. Even in the absence of data points, the ADTree method can be used to calculate a certain range of classification probabilities. After development of the prediction model, we validated the model using an independent validation dataset (n=56). Results: The developed model contained 14 variables and exhibited high accuracy; the area under the receiver operating characteristics curve was 0.89 (95% CI, 0.84 — 0.94) and 0.86 (95% CI, 0.76 — 0.95) for the training-and validation dataset, respectively. Bootstrap analyses yielded 0.90 ± 0.026 for training and 0.85 ± 0.053 for validation; the missing value replacement test showed 0.86 ± 0.011 for training and 0.83 ± 0.020 for validation.

Conclusions: The model permitted the accurate prediction of AxLN metastasis even in datasets with missing values. Furthermore, it incorporates a combination of clinicopathological variables that can be obtained non-invasively for their prediction. Thus, it may become a valuable tool for the development of treatment strategies.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-01-21.
Abstract P1-01-24: Is the Dye Method Alone Useful for Sentinel Lymph Node Biopsy in Early-Stage Breast Cancer? Prospective Analysis of 1081 Patients after SLN Biopsy
Authors: Iwase T , Nakamura R , Naohito Y , Kouya F , Toshi O , Miyazaki M.
Published: April 2011

Introduction: Sentinel lymph node biopsy (SLNB) for breast cancer has been established. The objective of this study was to investigate factors which elevate the identification rate employing the dye method (DYm) alone.

Subjects: The subjects were 1,081 cN0 breast cancer patients who underwent preoperative cytology of the axillary lymph nodes at our facility between May 2001 and April 2010.

Methods: In the morning of the operation day, 0.3 ml of technetium phytate was subcutaneously injected immediately above the tumor, and 5 ml of indigocarmine was subcutaneously injected into the para-areolar region on the axillary side immediately before surgery, attempting to identify sentinel lymph nodes (SLN) using the combination method. The rates of identification employing the DYm and RI method (Rim) and false-negative rates were calculated. Regarding SLN in which the highest count was detected by the RIm as the first SLN (fSLN), consistency with that detected using the DYm was investigated.

Results: The mean numbers of SLN identified by the DYm and RIm were 1.36 and 1.90, respectively, showing that significantly more lesions were identified employing the RIm (P<0.05). The identification rates employing the dye, RI, and both methods were 88.7, 98.7, and 99.3%, respectively, and the consistency of fSLN between the DYm and RIm was 78.1%. SLN metastasis detected using the RIm could not be identified employing the dye method in 20 cases. The age, tumor size, and BMI were investigated in these 20 cases, and a significant difference was noted in the tumor size. Conclusion: The identification rate employing the DYm alone was lower than that employing the RIm. The consistency of fSLN between the two methods was 78.1%. Although the RIm may have biopsied excess lymph nodes (LN), its use may be important to complement the DYm. Dye does not readily enter metastatic LN because of the presence of tumor plugs. The application of preoperative axillary LN cytology to cases with large tumors to exclude metastasis-positive cases may elevate the SLN identification rate employing the DYm.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-01-24.
Abstract P1-01-28: Utility of 18F-Fluoro-Deoxyglucose Emisión Tomography/Computed and Sentinel Node Biopsy for Axillary Staging in Primary Breast Cancer. Roffo PET/CT 1 Trial
Authors: Noblia CM , Cresta Morgado CE , Azar ME , Bruno G , Gonzalez C , Parma P , Gonzalez EG , Armanasco E , Montoya D , Ipiña JM , Zarlenga C , Gorostidi S.
Published: April 2011

Objetive 1. - To compare the capacity of the PET and the sentinel node for the detection of axillary metastasis (MTS). 2. - To evaluate sensitivity, specificity, positive and negative predictive value of the PET/CT. Inclusion criteria-Breast cancer T1 T2 NO. Palpable nodes suspicious of involvement. Exclusion criteria-Ductal carcinoma in situ, inflammatory carcinoma, recent biopsy of the breast, pregnancy or lactation, diabetes. Method 18-FDG PET/CT was made 15 days before the surgery. The sentinel node biopsy took place with the combined method (radioisotopes and patent blue)

Material They were evaluated 54 patients. Age average: 59 years (37-79). T1: 36 patients (67%); T2: 18 patients (33%) Tumor size between 5 and 40 mm (average 19) clinically negative axilla 46 (85%); doubtful axilla 8 (15%). Stage I: 33 patients (61%); stage II: 21 patients (39%). Results Forty four (81%) of the tumors were invasive ductal carcinoma: 7 (13%) invasive lobular carcinoma; and 3 (6%) ductolobular. Fifteen patients had MTS in the SN (28%), of these 3 were micrometastasis. In 2 patients the PET/CT changed the stage since it was positive for bony and pulmonary MTS.

Results PET in breast: Eleven negatives (FN: 20%). Four were invasive lobular carcinomas; 4 were T1a. Sensitivity 80%. VPP = 100%. False negative: 20%Result PET in axila: In 45 patients the PET was negative (83%). Six of them presented MTS in the sentinel node; 3 of them were micrometastasis. False negative: 40%. Sensitivity: 60%.VPN 87%. In 9 patients the PET were positive (17%) and the sentinel node was positive in all the cases. Specifity: 100%. VPP = 100%. In 8 patients the axilla was doubtful, of these only in one patient PET and the SN was positive. Conclusion 1.-PET/CT does not contribute advantages for the axillary staging in the initial stage because it does not manage to identify smaller MTS of 5 mm. 2.- A negative PET/CT does not replace the sentinel node biopsy. 3.- A positive PET/CT would indicate the necessity of making an axillary dissection still in clinically negative axilla. 4- In clinically doubtful axilla was coincidence between PET/CT and the SN as much in the negatives as in the positives.

Key words: Occult axillary metastases. Positron emission tomography. Sentinel node biopsy.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-01-28.
Abstract P1-01-30: True Sentinel Nodes Identified by CT-Lymphography Accurately Stage the Axilla in Patients with Breast Cancer: Removal of True Sentinel Nodes Alone Is Sufficient
Authors: Motomura K , Ishitobi M , Komoike Y , Koyama H , Inaji H , Horinouchi T , Nakanishi K.
Published: April 2011

Background: Sentinel node biopsy (SNB) using dye and/or radioisotope often results in the identification and removal of multiple nodes as sentinel nodes (SN), although most of these nodes may be non-SN. CT-lymphography (CT-LG) can distinguish true SN from non-SN because of the visualization of the lymphatic channel. This study investigated whether true SN identified by CT-LG accurately stage the axilla in patients with breast cancer, making it sufficient to remove true SN alone.

Methods: This study included 168 patients with breast cancer with clinically negative nodes. Contrast agent was injected intradermally into the skin overlying the breast tumor and in the subareolar region. True SN were identified by CT-LG. Marking the location of true SN was performed on the skin surface using a CT laser light navigator system. SNB was performed using a combination of dye and radioisotope. Lymph nodes located just under the marking were first removed as true SN. Then, all dyed nodes or all hot nodes were removed.

Results: The mean number of true SN identified by CT-LG was 1.1 (range 1-3). The mean number of hot and/or dyed nodes removed was 1.8 (range 1-6). One hundred forty-seven patients (87.5%) had 1 true SN removed, 19 (11.3%) had 2 true SN removed, and 2 patients (1.2%) had 3 true SN removed. Twenty-one (12.5%) patients had ≥2 true SN removed, whereas 91 (54.2%) of patients had ≥2 hot and/or dyed nodes removed (P<0.0001). Pathologic evaluation demonstrated that 38 (22.6%) of 168 patients had metastasis to at least one node. All of these 38 patients demonstrated metastases to at least one of the true SN identified by CT-LG. There were no adverse events associated with CT-LG.

Conclusions: True SN identified by CT-LG accurately staged the axilla in patients with breast cancer. Removal of true SN alone may reduce the postoperative morbidity and cost of the procedure by decreasing the surgical duration as well as the cost of pathologic analysis.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-01-30.
Abstract P1-02-02: Processing of GPNMB by ADAM-10 in Breast Tumors Releases an Extracellular Domain with Angiogenic Properties
Authors: Rose AAN , Annis MG , Dong Z , Pepin F , Hallett M , Park M , Siegel P.
Published: April 2011

Background: Glycoprotein non-metastatic B (GPNMB), also known as Osteoactivin, is a cell surface bound, transmembrane protein that is expressed in 41-74% of breast cancers. We have shown that it promotes migration, invasion and metastasis of breast cancer cells, that it is associated with shorter recurrence-free and overall survival times, and that it is most commonly expressed among breast tumors of the basal/triple-negative subtypes. Patients with basal/triple-negative breast cancer have aggressive disease and are not amenable to currently available targeted therapies. For these reasons GPNMB is an attractive target for therapeutic intervention in breast cancer; indeed, a GPNMB-targeted antibody-drug conjugate (CDX-011) has shown impressive clinical response among patients with GPNMB-positive breast cancer and is being investigated in Phase IIb clinical trials. Despite its promise as a therapeutic target in breast cancer, little is known about the functional role of GPNMB the primary tumor microenvironment.

Materials and Methods: We have employed 66cl4 murine mammary carcinoma cells and human BT549 breast cancer cells to investigate the effects of GPNMB on tumor growth and angiogenesis, respectively in vivo. Control and GPNMB-expressing tumors were analyzed using immunohistochemistry for degree of proliferation apoptosis and angiogenesis. To better characterize functionally important domains of GPNMB we employed immunoblot and ELISA analyses to assess levels of full length, intact GPNMB and shed GPNMB ectodomain in breast cancer cells. Transient siRNA-mediated knockdown studies were used to identify sheddases responsible for GPNMB shedding. Finally, we employed in vitro migration assays to assess function of the shed extracellular domain (ECD) of GPNMB.

Results: In this study we show that GPNMB promotes the outgrowth of mammary tumors in vivo and enhances their microvascular density. In an effort to investigate the functional domains of GPNMB that are responsible for this pro-angiogenic effect, we found that that the extracellular domain (ECD) of GPNMB is constitutively shed in breast cancer cells and show that this ECD is capable of inducing endothelial migration. Finally, we have implicated a disintegrin and metalloprotease-10 (ADAM10) as a novel sheddase responsible for liberation GPNMB ectodomain.

Conclusion: In this study we have described ADAM10-mediated shedding of GPNMB ECD - a protein fragment that induces endothelial cell migration - as a novel mechanism by which GPNMB can promote angiogenesis in breast cancer. Further efforts to characterize the effect of GPNMB on endothelial cell function will be discussed.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-02-02.
Abstract P1-02-03: JAM-2, Junctional Adhesion Molecule-2 Influences the Adhesion and Migration of Vascular Endothelial Cell
Authors: Al-Mrabt N , Martin TA , Jiang WG
Published: April 2011

Background. Junctional Adhesion Molecule (JAM)-2, is a protein that belong to the JAM Ig superfamily. JAM-2 is primarily found in vascular endothelial and epithelial cells and considered key to the making of the brain blood barrier (BBB). JAM-2 is located in the tight junction region in the cells and, via the homotypic interactions, regulates the rolling and adhesion of lymphocytes, NK cells, dendritic cells and platelets over the endothelium lining in the blood stream. It has also been indicated to possibly influence the rolling of tumours cells over endothelial cells. Little is known with regard to the biological influence of JAM-2 on endothelial cells. In the present study, we investigated the impact of JAM-2 on the biological behaviour of vascular endothelial cells. Materials and methods. Human vascular endothelia cell, HECV was used. Anti-JAM-2 ribozyme transgenes were constructed based on the secondary structure of human JAM-2 and were used to transfect HECV cells in order to knock down the expression of JAM-2 in the cells. The attachment of the cells to matrix surface and the cellular migration were determined using a Electric Cell-substrate Impedance Sensing (ECIS) method. The tight junction function, trans-endothelial electric resistance (TER) was evaluated using a two chamber cell model with an EVOM voltammeter. In vitro tubule forming was assessed using a sandwich tubule forming assay. Results. The Vascular endothelial cell, HECV, expressed JAM-2 in its wild type as shown by RT-PCR. We created JAM-2 knockdown sublines, HECVΔJAM2, by way of ribozyme transgenes. Knocking down JAM-2 resulted in a rapid rise of cell adhesion (297.7±8.4 in control cells, P<0.0001 vs 364.9±19.7 in ohm vs HECVΔJAM2 cells, at 4000Hz), over a 2 hour period. Likewise, HECVΔJAM2 cells displayed a rapid rise in cellular migration when compared with control cells. This was observed over a wide frequencies (250-10,000Hz) (1046.5±8.9 for control cells and 1139.4±24.0 for HECVΔJAM2 cells at 250Hz, P<0.001).It is interesting to note that there was no significant difference in TER in control cells and HECVΔJAM2 (p=0.116). In the tubule forming assay, it was demonstrated that HECVΔJAM2 formed less tubules in comparison with control cells, although this is not statistically significant (p=0.061), Conclusion. JAM-2 has a profound impact on the adhesion and cellular migration of endothelial cells. It also influences the transendothelial resistance and tubule forming of the cell, although to a lesser content. Together with the knowledge on its role in lymphocyte/tumour-endothelial interaction, JAM-2 may have a role in the extravasation process of cancer cells.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-02-03.
Abstract P1-03-01: Generation of a Novel In Vivo Model of Patient-Derived Chemoresistant Breast Cancers
Authors: McAuliffe PF , Gonzalez-Angulo AM , Sharma C , Singh G , Akcakanat A , Meric-Bernstam F.
Published: April 2011

Background: Breast cancer patients who have significant residual cancer after neoadjuvant chemotherapy (NCT) are at high risk of relapse. There is a pressing need to identify novel therapeutics that can be offered to these patients. In vivo models available to test new agents are limited. We hypothesized that tumors from patients with poor response to NCT can be transplanted into nude mice to establish xenografts, providing a novel in vivo model to study therapies for chemoresistant tumors. Materials and Methods: After informed consent, excess tumor was taken from the mastectomy specimens from six patients who had either disease progression during NCT or significant residual disease after NCT. On surgical pathologic evaluation, average tumor size was 8.6 ± 3.2 cm (range 4.5-12 cm), and average number of positive lymph nodes was 6.2 ± 6.8 (range 0-18). Patients had RECIST criteria of partial response (n=2), stable disease (n= 1) or progressive disease (n=3). For each patient, tumors were implanted subcutaneously into the flanks of five nude mice. Tumors were passaged to successive generations when they reached 1.5 cm in diameter. In vivo tumor growth and the ability to serially passage tumors were assessed. Patient and tumor characteristics, and patient outcomes were evaluated.

Results: Three patients had ER+HER2- tumors and three had ER-HER2- tumors. Serially transplanted xenografts were established from all six patients (100%); see Figure 1. Within each group of five mice implanted with the human tumors, 60 ± 26% developed tumor. Time to tumor size of 1.5 cm diameter was 4.2 ± 2.6 months (range 1.5-7.8 months). Two mice also developed tumors at a location distant from the implantation site (Met). These tumors were separately engrafted, also with 100% take, reaching 1.5 cm diameter at 1.5 and 1.7 months. Of the six patients, one had metastatic disease at surgery and underwent palliative mastectomy. Of the other five patients, four (80%) developed metastatic disease 4-8.4 months after surgery. Mice developed passagable tumors at least 2 months before the donor patients developed distant recurrence. The one patient who remains distant disease-free had the longest time to tumor passage (8.4 months).

Figure 1. Time to passage of tumor to next generation of mice. Flank tumors xenografts were derived from patients with chemoresistant breast cancers. When tumors reach 1.5 cm in diameter, they are passaged to the next generation of 5 mice. X-axis depicts time to reach 1.5 cm with each passage.

Discussion: Patients with progression or significant residual disease after NCT are at very high risk of distant relapse. Their chemoresistant tumors can be used to create serially transplantable xenografts. This in vivo model of chemoresistant breast cancer may be utilized to allow individualization of additional adjuvant or metastatic breast cancer treatment.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-03-01.
Abstract P1-03-06: Population Based In Vivo Biomarker Discovery Using Engineered Human Tumors
Authors: Wu M , Clark K , Deng N , Cai Z , Nicoletti R , Sun K , Feng B , Heyer J , Chiu I , Robinson M.
Published: April 2011

Background:

Tumors from patients exhibit significant inter-tumor variation, where each tumor harbors a unique set of genetic alterations that impact prognosis and response to treatment. Unfortunately, this variation contributes to low response rates in the clinic and creates significant challenges for treating patients with appropriate drugs. Cancer cell line based xenografts have traditionally been the preclinical model of choice to assess the efficacy of clinical compounds; however, such in vitro models exhibit inherent artifacts, and are unable to adequately capture natural variation seen in human tumor populations. It has therefore become a priority in oncology and personalized medicine to match patients to drugs that will result in a favorable treatment outcome. In this report, we describe a population based approach for response prediction featuring naturally occurring variation in tumors derived from genetically defined human-in-mouse models of cancer. Materials and Methods:

A population of De novo human breast tumors were generated by genetically engineering normal primary human breast epithelial cells with HER2 and SV40 early region (HER2/SV40er) or KRAS and SV40 early region (KRAS/SV40er) in an in vivo Human-In-Mouse (HIM) tissue transgenic model (Wu et al, Proc Natl Acad Sci U S A 2009, 106: 7022-2027). Each tumor of the population has been comprehensively characterized histopathologically, and at the RNA and DNA level. Furthermore, the population has been adapted to conduct quantitative efficacy studies of anti-cancer agents and combinations. Results:

The HER2/SV40er and the KRAS/SV40er HIM tumors develop as invasive human breast adenocarcinoma that are histologically similar to those observed in patients. Microarray and CGH profiling demonstrated significant inter-tumor variation among the established tumors, as has been reported for patient tumors. Moreover, the KRAS/SV40er tumors clustered with basal type breast cancers from patients, a poor prognosis human breast cancer subtype. Both HER2/SV40er and KRAS/SV40er tumors exhibited variable responses to treatments with the potent selective triple VEGFR inhibitor, tivozanib. Further characterization of those tumors, both pre-and post-treatment, identified potential biomarkers for tumor response to tivozanib. Discussion:

The genetically defined human-in-mouse tumors exhibited natural variations similar to that occurs in human cancer. This population-based HIM system enables us to identify and validate biomarkers of therapeutic response in an in vivo human tumor model. Figure available in online version.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-03-06.
Abstract P1-03-11: Combination of nab-Paclitaxel and Bevacizumab Inhibited Tumor Growth and Metastasis of a New Triple Negative Breast Cancer Model
Authors: Ran S , Trieu V , Volk LD , Wilber A , Desai N.
Published: April 2011

Background: Triple-negative breast cancers are highly aggressive and resistant to chemotherapy. In this study, we established a new model of triple-negative breast cancer and used it to test the novel combination of nab-paclitaxel with anti-VEGF antibody bevacizumab, which has been effective in treating other metastatic cancer types. Methods: The triple-negative HCC1806 beast cancer cells were stably transfected with dual reporters Red Fluorescent Protein (RFP) and Renilla luciferase to establish the new HCC1806-RR model. Immunodeficient mice bearing orthotopic HCC1806-RR tumors of 150mm3 in size were treated with saline (control), bevacizumab (4 mg/kg. i.p., twice a week, for 10 weeks), nab-paclitaxel (10 mg/kg, i.v., qdx5), or with combination of nab-paclitaxel and bevacizumab. Metastasis was analyzed by measuring luciferase activity in the lymph nodes (LN) and lungs. Results: The HCC1806-RR cells had identical morphology, proliferation rates and sensitivity to nab-paclitaxel as the parental HCC1806 cell line. HCC1806-RR tumors primarily metastasized to LN, with lung being a secondary metastatic site. Combination therapy of nab-paclitaxel and bevacizumab inhibited tumor growth by 100%, as compared to 0% for bevacizumab (P < 0.001) and 90% for nab-paclitaxel (P = 0.024). Importantly, only combination therapy reduced incidence of LN and lung metastases by 50% (P = 0.007) and 87% (P = 0.001). Overall, 50% of the mice in the combination therapy group (n = 10) had complete regressions of both primary tumors and metastases at both regional and distant sites. Conclusions : The HCC1806-RR is a new triple-negative breast model with dual reporters to allow for quantitative assessment of metastatic spread. This model can be used to study the biology and treatment of triple-negative breast cancer. Combination of nab-paclitaxel with bevacizumab was highly effective against HCC 1806-RR tumors, suggesting that this regimen could provide clinical benefits to patients with triple-negative breast cancers.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-03-11.
Abstract P1-08-03: Alternative Dosing Regimens with Tarceva in a Mammary Cancer Model: Effects on Efficacy and Potential Effects on Toxicity
Authors: Lubet RA , Iwata K , Szabo E , Grubbs CJ.
Published: April 2011

The EGFR inhibitors (e.g., Tarceva) have been effective in preventing cancer in multiple animal models, including ER positive breast, head and neck, and urinary bladder cancers. Although Tarceva is less toxic than most classical cytotoxic therapies, the development of a skin rash in greater than 35% of patients is a significant impediment to its use in a preventive setting. We, therefore, tested whether alternative dosing regimens would still achieve preventive efficacy. Female Sprague-Dawley rats were administered a single IV dose of methylnitrosourea at 50 days of age. Beginning 5 days later, rats were administered Tarceva (6 mg/kg BW) by gavage. In the first study, three different protocols were employed: (1) dosing with Tarceva daily (7X/week), (2) dosing with Tarceva for one day followed by one day of vehicle treatment, and (3) two days of dosing with Tarceva followed by two days of dosing with vehicle treatment. These treatment regimens resulted in 94, 58, and 77% decreases, respectively, in cancer multiplicity when compared to rats receiving vehicle alone. In a second ongoing study, we are evaluating the following alternative dosing schedules. MNU treated rats are receiving either: (1) daily dosing with 6 mg/kg BW (total of 42 mg/week); (2) dosing 6 mg/kg BW, 2 days on-2 days off (total of 21 mg/week): (3) weekly dosing with a single dose of 42 mg; and (4) daily dosing with the vehicle. The various Tarceva treatment regimens have currently reduced palpable mammary tumor multiplicity by 82, 66, and 71%, respectively. These data imply that by significantly altering the dosing of Tarceva, including a dose of once per week, most of the preventive efficacy is retained. Pharmacokinetic studies from these protocols showed a t½ of <8 hours; implying that sub-effective serum levels were achieved within 48 hours of the last dose. Whether these altered protocols may affect the induced skin rash in women is a significant and practical question. Supported by NCI contract number HHSN261200433001C.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-08-03.
Abstract P1-08-04: Doses of Selective Estrogen Receptor Modulations (SERMS) Required for Prevention and Therapy of Chemically-Induced Mammary Cancers
Authors: Heckman-Stoddard BM , Grubbs CJ , Johnson K , Lubet RA.
Published: April 2011

Selective Estrogen Receptor Modulators (SERMs) interfere with the activation of the estrogen receptor. SERMs have been shown to be effective for both treatment and prevention of breast cancer. Here we examine the ability of tamoxifen and arzoxifene, a more easily absorbed form of raloxifene, to prevent mammary tumors at a significantly lower dosage than those used for treatment. For prevention studies, female Sprague-Dawley rats (50 days of age) were injected with a single i.v. dose of MNU resulting in the development of multiple ER-positive mammary tumors beginning 7 weeks after carcinogen treatment. Rats were administered the preventive agent beginning five days after carcinogen administration. When the agents were tested at does varying between 0.15-3.3 ppm in the diet, both agents caused a dose dependent increase in preventive activity. The highest doses of tamoxifen (3.3 ppm) and arzoxifene (3.0 ppm) both decreased tumor multiplicity greater than 90%. Both of these doses are less than one-fifth the human equivalent dose (HED) based on standard FDA scaling factors. Both doses also resulted in substantial decreases in mammary gland development. These dosages were then used in a therapy setting to compare the efficacy. For these studies, MNU treated rats were allowed to develop their first palpable mammary tumor (70-150 mm2) before initiating treatment. Tumor growth or regression was followed by caliper measurements. Neither of the preventive doses of these SERMs exhibited therapeutic activity although substantially higher doses of tamoxifen (33 or 100 ppm) were relatively effective. These results are in contrast to our prior findings with other classes of agents (RXR agonists, EGFR inhibitors, and aromatase inhibitors) in which highly effective preventive doses were as effective as therapeutic doses in this model. These results demonstrate the unique dose differential regarding prevention and therapy with SERMs. Microarray analysis of tumors treated for 5 days with tamoxifen at doses of 3.3ppm or 100ppm reveals overlapping significant gene changes of similar magnitude in comparison to control treated tumors although there were significant gene changes seen at the therapeutic dose which were not observed at the lower dose. These studies raise two questions: 1) whether this class of agents might be used at significantly lower doses in a pure prevention setting as contrasted with a therapeutic setting where they were initially defined; 2) are there gene expression changes which might be used to help identify this differential dosing for prevention vs. therapy.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-08-04.
Abstract P1-09-05: Re-Testing of HER2 Status in Recurring Metastatic Breast Cancer Is a Clinically Relevant and Cost-Effective Strategy
Authors: Bernow M , Wilking U , Bergh J , Jönsson B , Wilking N.
Published: April 2011

Introduction

Previously HER2 status has been shown to change in 6 to 30% of recurring metastatic breast cancer (RMBC) patients (pts). Still most clinicians base trastuzumab (TZ) re-treatment decisions on prior HER2 testing of the primary tumor. This study investigates cost-effectiveness of re-testing of HER2 status (REHER) of metastasis in RMBC pts before TZ treatment in a Swedish setting. Materials and methods

A Markov state transition model is used to simulate six different strategies for REHER and treatment of RMBC. The analysis is performed for two cohorts with different patient management and resource use, based on:

I Treatment guidelines and published data on the patient group (guideline cohort, GC);

II Clinical practice with real life data from a Swedish breast cancer database (real life cohort, RLC).

Quality adjusted life year (QALY) weights and risks of progression and breast cancer death are taken from literature. Outcomes are measured as QALYs gained and costs, including both direct and indirect costs. Analyses are performed with life time perspective and both costs and outcomes are discounted at 3%. Costs have been converted to USD with an exchange rate of 7.367 SEK/USD.

Testing and treatment strategies.

Results

Chemotherapy alone for all pts (strategy 0) is least costly and results in 1.309 QALYs gained. IHC testing all pts and treat FISH confirmed IHC 2+ 3+ pts with TZ (strategy 4) has lowest incremental cost-effectiveness ratio (ICER), $63,200 and $61,100 for GC and RLC respectively. FISH testing all pts and treating FISH+ with TZ (strategy 5) is the most efficient strategy resulting in 1.543 QALYs gained with an ICER at $75,500 and $73,300 respectively. Strategies 1 and 3 are dominated by simple dominance (less expensive alternative with better outcome). Strategy 2 is dominated by extended dominance (alternative with better effectiveness and lower ICER).

Results for guideline and real life cohorts.

Conclusion

The cost of patient management calculated based on guidelines is similar to the one based on observed clinical practice. RLC is less costly but both cohorts give the same ranking of strategies. A Swedish study estimated willingness to pay (wtp) in Sweden to 88,900 $/QALY gained. If TZ treatment is an option REHER of metastasis is clinically relevant and cost-effective. Depending on the wtp strategies 4 and 5 can be considered. Interesting to notice is that strategy 1 (no re-testing of metastasis), probably the most common one used, is dominated and thus suboptimal regardless of wtp per QALY.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-09-05.
Abstract P1-09-08: Survival, Health Care Cost and Utilization of Patients with Triple Negative Breast Cancer in a U.S. Managed Care Setting
Authors: Baser O , Wei W , Henk HJ , Xie L , Teitelbaum A.
Published: April 2011

Objectives: Triple negative breast cancer (TNBC), a subtype of breast cancer characterized by its unique molecular profile and aggressive clinical behavior, lacks satisfactory standard therapies. Little is known about survival and economic cost of patients with TNBC. This study was conducted to compare the survival, health care cost and utilization of patients with TNBC versus patients with breast cancer that is not triple negative.

Methods: Analyses were conducted using Impact Intelligence Oncology Management (IIOM) (2002-2009) linked with United Health administrative claims. Patients were followed from the time of initial breast cancer diagnosis until death, disenrollment or end of the observation period. Continuous enrollment was required during the observation period. Staging and estrogen and progesterone receptors (ER/PR) and HER2 status were obtained at time of initial diagnosis. Patients’ age, region, cancer stage, comorbid conditions, health care costs and utilization prior to the initial diagnosis were controlled for risk-adjusted comparison. Cox regression was used for survival analysis. Health care resource use during the follow-up after initial diagnosis, such as number of hospitalizations, emergency room (ER) visits, office visits, outpatient visits and oncologist visits, were modeled with negative binomial regression. Since variable length of follow-up is allowed in the study design, we used inverse probability weight adjusted generalized linear models to estimate risk-adjusted annual total health care costs. Using a similar approach, we compared adjusted inpatient, pharmacy, office, outpatient, emergency and other costs between both groups.

Results: The study included 450 patients with TNBC and 1,807 patients without TNBC. At time of diagnosis, TNBC patients were younger (54 vs. 57, P<0.001) than patients with no TNBC. After controlling with baseline differences, overall mortality risk rate for TNBC patients were over two times higher (HR: 2.15, P<0.002). Stratified Kaplan-Meier (KM) analysis showed that the best survival rates were for stage I-III non-TNBC patients, followed by stage IV non-TNBC patients and stage I-III TNBC patients. The highest death rates occurred for stage IV TNBC patients. Adjusted comparison showed that patients with TNBC had significantly more annual number of hospitalizations, hospitalization days and number of ER visits relative to non-TNBC patients (1.28 vs. 0.95 P<0.001, 10.20 vs. 6.07 P<0.001, 1.30 vs. 0.93, P<0.003). Although similar in annual total health cost, total adjusted inpatient costs for TNBC patients were almost 50% higher ($9,581 vs. $6,506, P<0.001).

Conclusions: The economic and clinical burden of patients with TNBC is significant versus patients with breast cancer that are not triple negative.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-09-08.
Abstract P1-10-06: Racial Disparities in Physical and Functional Domains in Women with Early Breast Cancer
Authors: Morehead Gee A , Pfalzer L , Stout N , Levy E , McGarvey C , Springer B , Soballe P , Gerber L.
Published: April 2011

Background. There is limited research on the racial/ethnic disparities in breast cancer survivors’ (BCS) physical functioning and quality of life (QOL). Previous studies note that African American (AA) women are typically diagnosed with larger, more aggressive tumors and require more intensitve surgical and adjuvant treatment potentiating higher levels of functional morbidity. Reasons given for these disparities include; genetic predisposition, poor access to screening and cultural norms that may impact a patients willingness to seek screening and early treatment. This analysis compared the QOL and prevalence of physical impairments (including lymphedema, seroma, cording) of white and African-American BCS from a US Military hospital where all patients have coverage and access to health care services. Methods. Data was analyzed from 166 women (130 white and 28 African-American). Participants were assessed preoperatively and examined at 1, 3, 6, 9, 12-24 months post surgery for impairments by a physical therapist. QOL was assessed at 12-24 months post-operation through the Short Form Health Survey (SF36v2). Analysis of variance estimated differences in QOL and occurrences of impairments between white and African-American BCS. Results. African-American BCS: were premenopausal(P<.05), had ER/PR negative tumors(P<.001, P<.05), and received radiation(P<.05). No significant differences were found in type, stage, grade, or size of BC tumor, surgery type, lymph node dissection, or number of lymph nodes sampled. More AA BCS were employed(P<.05) and socially active(P<.05), but less recreationally active(P<.05); there were no significant differences in marital status. More AA BCS had axillary web syndrome(P <.05) and lymphedema(P <.05). No significant differences were found in seroma, fatigue, chestwall pain, shoulder pain, numbness, and self-reported QOL. Conclusions. Results suggest a difference in physical effects of BC treatment on white and AA women; however, contrary to other studies, no differences in QOL were noted. Our cohort demonstrates an interesting trend, in that only ER/PR status differed and other characteristics of the tumor were not different between racial groups. This differs from past reports and may suggest that access to care plays a role in promoting earlier stage diagnosis. However, despite the homogeneity of our cohorts tumor status we found that AA BCS may be at a higher risk for common impairments associated with BC treatment and should be monitored prospectively to mitigate the potential for impairments. Further research should examine effects of BC treatments on women of various ethnicities.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-10-06.
Abstract P1-10-08: Breast Reconstruction Surgery Following Mastectomy: Love or Money?
Authors: Al-Allak A , Knight H , Walter C , Court F , Chan HY.
Published: April 2011

Introduction

All women should be considered for breast reconstruction following mastectomy, providing they are medically fit. The proportion of women having a reconstruction varies significantly from centre to centre; a key reason for this is the availability of reconstruction in that centre. In countries with an insurance funded health care system, breast reconstruction may also be influenced by the ability to pay. In the UK, breast reconstruction is available for free on the National Health Service (NHS). The aim of our study was to identify any other factors that may influence a woman's decision to have a reconstruction. Methods

All women having a mastectomy under the care of one breast surgeon between 2000 and 2010 were included. Data were collected retrospectively and included: age at surgery, marital status, dependents under 18, employment status, home circumstances and Zip code. The Index of Multiple deprivation (IMD2007) was derived for each patient from their zip code using the UK National Statistics data. The patients were divided into two main groups: those who underwent reconstruction and those who opted for mastectomy only. The Mann-Whitney U test was used to determine whether there was a statistical difference between the two patient groups using the statistical package R.

Results

A total of 272 patients underwent mastectomy during the study period, of these patients 148 had mastectomy only (median age 67, range 34 — 95) and 124 had a reconstruction (median age 51, range 28-73). When the two groups were compared statistical analysis revealed that the reconstruction group were younger (P<0.002), more likely to be married or have a partner (p=0.00065), have dependents (P<0.0005) and work (P<0.0005). There was no significant difference between the two groups socioeconomic status.

Conclusion

These data suggest that social and economical inequalities do not affect the decision making process for breast cancer patients in a society where health care is free at the point of delivery. However young age and a stable family/partner do.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-10-08.