Abstract 1608: CTC categorization: Subpopulations of CTCs and their potential clinical significance

Abstract Circulating tumor cells (CTCs) were previously rare events difficult to identify. In clinical practice, CTC enumeration has now been recognized for its prognostic value. Furthermore, as CTC technology has rapidly improved, CTCs are now readily available for further investigation. The tumor cells isolated from CTC instruments may be analyzed for molecular profiles and mutation screening. Here we propose three new subsets of CTCs: elongated CTC (EL-CTC), miniature CTC (Mini-CTC) and cluster CTC (CL-CTC). Elongated CTC have an elongated shape and some of these cells have an enlarged tail composed of the nucleus. The enlarged tail is formed during intravasation because of the less flexible nuclear membrane and these cells represent highly motile tumor cells. The mini-CTCs are much smaller than regular tumor cells and may be dormant and gain the advantage of escaping immune surveillance. The CTC clusters are formed by a group of tumor cells and lymphocytes as well as macrophages. There is strong evidence that these clusters are highly malignant. These three subsets are recognized morphologically and their unique features may directly relate to their functionality and clinical significance. Additional investigation in the area of CTC research, specifically enhanced understanding of CTC subpopulations, may lead to novel therapeutic approaches in oncology. Citation Format: Chengsen Xue, Thomas W. Mc Closkey. CTC categorization: Subpopulations of CTCs and their potential clinical significance. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1608. doi:10.1158/1538-7445.AM2015-1608