A lung cancer evaluating system, comprising: a processor; a memory unit which stores at least one classifier generated according to an analysis of a plurality of historical blood test results of each of another of a plurality of sampled individuals; an input unit which receives a plurality of current blood test results taken from a blood of a target individual; and a lung cancer evaluating module which evaluates, using said processor, a lung cancer risk of said target individual by classifying, using said at least one classifier, a set of features extracted from said plurality of current blood test results; characterized by: each of said plurality of historical and current blood test results comprises at least the following 18 blood test results: red blood cells; white blood cell count - WBC; mean platelet volume; hemoglobin; hematocrit; mean cell volume; mean cell hemoglobin; mean corpuscular hemoglobin concentration (MCHC); red cell distribution width; platelet count; eosinophils count; neutrophils percentage; monocytes percentage; eosinophils percentage; basophils percentage; neutrophils count; monocytes count; and Platelets hematocrit; and said at least one classifier comprises a member of a group consisting of: a weighted linear regression classifier, a K-Nearest neighbors classifier, and a random forest classifier. a processor; a memory unit which stores at least one classifier generated according to an analysis of a plurality of historical blood test results of each of another of a plurality of sampled individuals; an input unit which receives a plurality of current blood test results taken from a blood of a target individual; and a lung cancer evaluating module which evaluates, using said processor, a lung cancer risk of said target individual by classifying, using said at least one classifier, a set of features extracted from said plurality of current blood test results; characterized by: each of said plurality of historical and current blood test results comprises at least the following 18 blood test results: red blood cells; white blood cell count - WBC; mean platelet volume; hemoglobin; hematocrit; mean cell volume; mean cell hemoglobin; mean corpuscular hemoglobin concentration (MCHC); red cell distribution width; platelet count; eosinophils count; neutrophils percentage; monocytes percentage; eosinophils percentage; basophils percentage; neutrophils count; monocytes count; and Platelets hematocrit; and said at least one classifier comprises a member of a group consisting of: a weighted linear regression classifier, a K-Nearest neighbors classifier, and a random forest classifier. each of said plurality of historical and current blood test results comprises at least the following 18 blood test results: red blood cells; white blood cell count - WBC; mean platelet volume; hemoglobin; hematocrit; mean cell volume; mean cell hemoglobin; mean corpuscular hemoglobin concentration (MCHC); red cell distribution width; platelet count; eosinophils count; neutrophils percentage; monocytes percentage; eosinophils percentage; basophils percentage; neutrophils count; monocytes count; and Platelets hematocrit; and said at least one classifier comprises a member of a group consisting of: a weighted linear regression classifier, a K-Nearest neighbors classifier, and a random forest classifier.