Abstract 4726: Virus-guided fluorescence imaging of intraperitoneal free gastric cancer cells as a potential clinical biomarker

Abstract

Abstract Peritoneal dissemination is a common pattern of metastasis in patients with gastric cancer, and associated with worse prognosis. Peritoneal lavage cytology during the operation is an important factor in predicting future development of peritoneal metastasis and determining the treatment strategy, but its sensitivity and specificity are unsatisfactory. TelomeScan is an adenovirus engineered to replicate and express GFP only in telomerase-activating tumor cells, so that we can easily detect viable cancer cells even among numerous normal cells. We hypothesized that TelomeScan might be applicable to detecting free cancer cells in peritoneal wash. Methods: Peritoneal washes were obtained from 42 gastric cancer patients during operation. The number of GFP-positive cells was determined for each sample and compared with cytology results and clinicopathological data Results: Clinical stage was ranged from IA to IV, and thirteen cases were diagnosed as class IV or class V by peritoneal lavage cytology. More than 10 GFP-positive cells were detected in 12 out of 42 cases, and these cases showed a worse prognosis when compared to the other 30 cases. Conclusion: We were able to detect gastric cancer cells as GFP-positive cells in peritoneal wash using TelomeScan. Furthermore, the presence of GFP-positive cells in peritoneal wash was associated with worse prognosis. These results suggest that number of cancer cells detected by TelomeScan in the peritoneal wash may have important clinical implication as prognostic and therapeutic biomarkers in gastric cancer. Citation Format: Megumi Watanabe, Shunsuke Kagawa, Michihiro Ishida, Naoto Hori, Satoru Kikuchi, Shinji Kuroda, Hiroyuki Kishimoto, Masahiko Nishizaki, Hiroshi Tazawa, Toshiyoshi Fujiwara. Virus-guided fluorescence imaging of intraperitoneal free gastric cancer cells as a potential clinical biomarker. [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 4726. doi:10.1158/1538-7445.AM2014-4726