The disclosed methods and systems allow for a systematic quantification of the heterogeneity of disease states between different subjects on a molecular (e.g., gene or protein expression) level. One example embodiment of the invention is a method for determining a disease state of a patient. The method includes generating personalized biomarker expression perturbation profiles for a plurality of individual subjects with a disease. The profiles include representations of biomarker expressions that are perturbed beyond a threshold amount. The method also includes creating a disease module by combining representations of biomarkers from the personalized profiles. The disease module includes a network of representations of biomarkers having perturbations associated with the disease. The method also includes accessing biomarker data for the patient from a sample obtained from the patient and determining the disease state of the patient based on a comparison of the biomarker data and the disease module.