Cytopathologic Detection of Circulating Tumor Cells Using the Isolation by Size of Epithelial Tumor Cell Method

TLDR

Morphological detection of circulating tumor cells (CTCs) is a promising but potentially false‑positive approach in clinical oncology, requiring ancillary methods. The study tested the reliability of a cytomorphologic approach to identify CTCs by examining 808 blood samples with the isolation by size of epithelial tumor cell (ISET) method. Using the ISET method, 808 samples were processed and nonhematologic cells were classified into malignant, uncertain, or benign categories. CNHCs were detected in 11.1 % of nonmalignant and 48.9 % of malignant patients, with malignant‑feature CNHCs in 5.3 % and 43.1 % respectively, indicating the ISET method’s promise for cytopathologic CTC identification.

Abstract

Detection of circulating tumor cells (CTCs) morphologically may be a promising new approach in clinical oncology. We tested the reliability of a cytomorphologic approach to identify CTCs: 808 blood samples from patients with benign and malignant diseases and healthy volunteers were examined using the isolation by size of epithelial tumor cell (ISET) method. Cells having nonhematologic features (so-called circulating nonhematologic cells [CNHCs]) were classified into 3 categories: CNHCs with malignant features, CNHCs with uncertain malignant features, and CNHCs with benign features. CNHCs were found in 11.1% and 48.9% of patients with nonmalignant and malignant pathologies, respectively (P < .001). CNHCs with malignant features were observed in 5.3% and in 43.1% of patients with nonmalignant and malignant pathologies, respectively. Cytopathologic identification of CTCs using the ISET method represents a promising field for cytopathologists. The possibility of false-positive diagnosis stresses the need for using ancillary methods to improve this approach.