%0 Journal Article
%T Rapid Stereomicroscopic Imaging of HER2 Overexpression in Ex Vivo Breast Tissue Using Topically Applied Silica-Based Gold Nanoshells
%A Lissett R. Bickford
%A Robert J. Langsner
%A Joseph Chang
%A Laura C. Kennedy
%A Germaine D. Agollah
%A Rebekah Drezek
%J Journal of Oncology
%D 2012
%I Hindawi Publishing Corporation
%R 10.1155/2012/291898
%X Tumor margin detection for patients undergoing breast conservation surgery primarily occurs postoperatively. Previously, we demonstrated that gold nanoshells rapidly enhance contrast of HER2 overexpression in ex vivo tissue sections. Our ultimate objective, however, is to discern HER2 overexpressing tissue from normal tissue in whole, nonsectioned, specimens to facilitate rapid diagnoses. Here, we use targeted nanoshells to quickly and effectively visualize HER2 receptor expression in intact ex vivo human breast tissue specimens. Punch biopsies of human breast tissue were analyzed after a brief 5-minute incubation with and without HER2-targeted silica-gold nanoshells using two-photon microscopy and stereomicroscopy. Labeling was subsequently verified using reflectance confocal microscopy, darkfield hyperspectral imaging, and immunohistochemistry to confirm levels of HER2 expression. Our results suggest that anti-HER2 nanoshells used in tandem with a near-infrared reflectance confocal microscope and a standard stereomicroscope may potentially be used to discern HER2-overexpressing cancerous tissue from normal tissue in near real time and offer a rapid supplement to current diagnostic techniques. 1. Introduction Currently, breast cancer is the second leading cause of cancer-related deaths in women, and it accounts for approximately one-third of all cancers diagnosed in women in the United States [1]. To reduce cancer recurrence and progression, cancerous tissue must be completely eliminated, regardless of grade [2]. Surgical breast cancer therapy focuses on removing the primary tumor and identifying the possibility of metastatic disease from the evaluation of sentinel lymph nodes. Although some patients may require modified radical mastectomy, many patients with less-advanced breast cancer elect breast-conserving surgery. The presence of a positive surgical margin during these surgeries has been associated with lower rates of patient survival [3]. Due to residual cancer cells being left in many patients that undergo breast conservation therapy, as many as 40% of patients have experienced local breast cancer recurrence near the site of the original tumor [4]. Intraoperative treatment decisions are, therefore, absolutely critical. Presently, intraoperative tumor margin detection occurs primarily in specialized tertiary centers, such as The University of Texas M.D. Anderson Cancer Center (MDACC). In these centers, the resected tissue receives a preliminary evaluation by a pathologist while the patient remains in the operating room; if necessary, additional
%U http://www.hindawi.com/journals/jo/2012/291898/