Proof-of-Concept Study on Large Oncosomes Detection

This technical report presents a proof-of-concept study aimed at investigating the feasibility of using the RareCyte CTC platform for the enumeration of large oncosomes (LOs) in conjunction with circulating tumor cells (CTCs) and cell-free DNA (cfDNA) analysis. The study focuses on identifying patients with HER2 overexpressing tumors within a metastatic breast cancer cohort. The methodology involved establishing criteria for large oncosome identification and quantifying LOs in 15 patient specimens. Results indicate that LO counts were higher than CTC counts and showed a strong correlation with CTCs. The report details the successful identification of HER2+ LOs in a significant percentage of blood smears and discusses the implications of these findings for multimodal HER2 detection. The study concludes that integrating LO analysis with CTC and cfDNA assessments enhances the sensitivity and accuracy of liquid biopsy techniques, providing valuable insights into tumor biomarker status.