Abstract 7636: Quantitative analysis of colorectal adenocarcinoma images obtained by single-shot 17-plex staining followed by imaging with the Orion™ spatial biology platform

Abstract Background To understand the tumor microenvironment (TME), high resolution imaging of multiple biomarkers with whole slide context can be used as a basis for downstream biomarker quantitation and predicting patient outcomes1. Here we investigate a sample of invasive colorectal adenocarcinoma using whole slide, single-step high-plex staining and imaging at single-cell resolution followed by quantitative analysis. Methods The slide was stained in one round with a 17-plex immune-oncology panel then imaged in one round with the Orion™ spatial biology platform. Quantitative analysis was performed on the resulting TIFF file using the following pipeline: - Manually annotate regions of interest (ROI) on the tissue- Segment whole slide images into cells with UnMICST and S3segmenter - Import mask and clean data in QuPath - Generate primary feature data table with QuPath - Classify cells into populations in QuPath - Generate spatial biomarkers - Compare cell populations and their spatial interactions in the different ROIs. Results Data revealed a distinction between normal colonic epithelium, well-differentiated adenocarcinoma with immune cell collection, and an infiltrating border of the carcinoma. Differences in immune cell content and spatial organization were measured, and the infiltrating border found to contrast with other tumor regions by showing a lower proliferative fraction (Ki-67, nuclear) and differences in E-cadherin and cytokeratin expression patterns. Conclusions These data highlight the importance of sufficient plex, resolution and whole slide context to derive reliable spatial biomarkers of potential prognostic value. Further, hours vs. days speed for whole-section multiplexed biomarker quantitation, along with same-section conventional chromogenic analysis, makes this approach suited to multi-patient clinical studies. 1 JR Lin et al. , High-plex immunofluorescence imaging and traditional histology of the same tissue section for discovering image-based biomarkers, Nat Cancer, 4, 1036-1052 (2023). Citation Format: Edward Lo, Tad George, Selena Larkin. Quantitative analysis of colorectal adenocarcinoma images obtained by single-shot 17-plex staining followed by imaging with the Orion™ spatial biology platform abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts) ; 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84 (6Suppl): Abstract nr 7636.