A comparative study of circulating tumor cell isolation and enumeration technologies in lung cancer

Abstract

Circulating tumor cells (CTCs) have potential as diagnostic, prognostic and predictive biomarkers in solid tumors. Despite FDA approval of CTC devices in various cancers, their rarity and limited comparison between analysis methods hinder their clinical integration for lung cancer. This study aimed to evaluate five CTC isolation technologies using a standardized spike-in protocol: the CellMag ™ (EpCAM-based enrichment), EasySep ™ and RosetteSep ™ (blood cell depletion), and the Parsortix® PR1 and next generation Parsortix® Plus (PX+) (size-based enrichment). The Parsortix® systems were also evaluated for any difference in recovery rates between cell harvest versus in-cassette staining. Healthy donor blood (5 mL) was spiked with 100 fluorescently labeled H1975 lung adenocarcinoma cell line, processed through each system and the isolation efficiency was calculated. All tested systems yielded discordant recovery rates with the CellMag™ having the highest mean recovery (70 ± 14%) followed by the PR1 (in-cassette staining) with a recovery of 49 ± 2% while the EasySep™ had the lowest recovery (18 ± 8%). The CellMag™ and Parsortix® PR1 may have potential clinical applications for lung cancer patients, albeit needing further optimization and validation.