1：Experimental Design and Method Selection:

The study used immunohistochemical (IHC) staining to evaluate biomarker expression in tissue samples from patients with colorectal cancer and peritoneal metastasis. The TASC scoring system was referenced for target selection.

2：Sample Selection and Data Sources:

Formalin-fixed, paraffin-embedded tissue blocks were obtained from pathology archives of Erasmus Medical Center and primary care facilities for patients who underwent cytoreductive surgery and hyperthermic intraperitoneal chemotherapy between March 2014 and September

3：List of Experimental Equipment and Materials:

20 Equipment included StarFrost adhesive slides, EnVision FLEX Target Retrieval Solution, PT Link (Dako), Ultra Fast Scanner (Philips), antibodies (e.g., anti-CEACAM5, anti-cMet, anti-EpCAM, anti-FRα), and reagents like xylene, ethanol, H2O2, phosphate-buffered saline, 3,3′-diaminobenzidine, hematoxylin, Pertex.

4：Experimental Procedures and Operational Workflow:

Sections of 4 μm were sliced, deparaffinized, rehydrated, peroxidase blocked, antigen retrieved, incubated with primary antibodies overnight, washed, incubated with secondary antibodies, visualized with DAB, counterstained, dehydrated, mounted, and scanned. Hematoxylin and eosin staining was also performed.

5：Data Analysis Methods:

Biomarker expression was scored on a scale of 0 to 3+ for intensity and quartiles for percentage, combined into an expression score (0-12). Statistical analysis used SPSS and GraphPad Prism for Spearman correlation coefficients.