Abstract: Algorithm-based molecular assays that involve measurement of expression levels of prognostic and/or predictive genes, or co-expressed genes thereof, from a biological sample obtained from a cancer patient, and analysis of the measured expression levels to provide information concerning the likelihood of recurrence of colorectal cancer and/or the likelihood of a beneficial response to chemotherapy for the patient are provided herein. Methods of analysis of gene expression values of prognostic and/or predictive genes, as well as methods of identifying gene expression-tumor region ratios, tumor-associated stromal surface area, and gene cliques, i.e. genes that co-express with a validated biomarker and thus may be substituted for that biomarker in an assay, are also provided.