Lung Cancer Research Paper

Hindawi Publishing Corporation
International Journal of Surgical Oncology
Volume 2012, Article ID 861257, 12 pages doi:10.1155/2012/861257 Research Article
Assessing Breast CancerMargins Ex Vivo Using Aqueous
Quantum-Dot-Molecular Probes
Giang H. T. Au,1 Wan Y. Shih,1 Wei-Heng Shih,2 LinetteMejias,3 Vanlila K. Swami,3
KimberlyWasko,4 and Ari D. Brooks4
1 School of Biomedical Engineering, Science and Health Systems, Drexel University, 3141 Chestnut Street, Philadelphia,
PA 19104, USA
2Department of Materials Science and Engineering, Drexel University, 3141 Chestnut Street, Philadelphia, PA 19104, USA
3Department of Pathology and Laboratory Medicine, College of Medicine, Drexel University, 245 N 15th Street, Philadelphia,
PA 19102,
T. Au, [e-mail]
Received 10 August 2012; Revised 16 November 2012; Accepted 26 November 2012
Academic Editor: Sheldon Marc Feldman
Copyright © 2012 Giang H. T. Au et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Positive margins have been a critical issue that hinders the success of breast- conserving surgery. The incidence of positive margins is estimated to range from 20% to as high as 60%. Currently, there is no effective intraoperative method for margin assessment.
It would be desirable if there is a rapid and reliable breast cancer margin assessment tool in the operating room so that further surgery can be continued if necessary to reduce re-excision rate. In this study, we seek to develop a sensitive and specific molecular probe to help surgeons assess if the surgical margin is clean. The molecular probe consists of the unique aqueous quantum dots developed in our laboratory conjugated with antibodies specific to breast cancer markers such as Tn-antigen. Excised
There are two major steps that affect the sensitivity and specificity of
AQD-Tn mAb probe: blocking time and staining time. First, blocking time was investigated. Different time periods were examined and it was narrowed down to 15minutes as the sufficient blocking time. Smaller time intervals were studied to further shorten the blocking time. As shown in Figure 4(a), no BSA blocking resulted in strong nonspecific binding of the QD-mAb probe on liver’s surface both dorsal and ventral sides. As the blocking time increased, nonspecific binding decreased and reached the saturated point at 10 minutes. The integrated intensity was similar between 10 minute and 15 minute blocking (Figures 4(c) and 4(d)). This was also at the same level as a control liver without QD-Tn mAb probe exposure (data not shown). Therefore, 10 minutes blocking should be sufficient to prevent nonspecific binding
3.4. Simulation of Intraoperative Margin Assessment. As previously mentioned, although livers and kidneys showed no positive signal, they still had some background intensity around 400 × 106. Thus, this was the cut-off level to
International Journal of Surgical Oncology