FIELD: medicine. SUBSTANCE: method involves examining presence of anorexia, weight losses, determining peripheral blood for blood platelets, segmented, stab neutrophil, eosinophil leukocytes, general bilirubin, glucose and prothrombin index level. Then eosinophil population is counted and diagnostic index calculated from a formula IKB2=Glucose * PI /(GB * 10), where Glucose is the glucose concentration in blood, PI is the prothrombin index in %, GB is the general bilirubin in mmole/l. Three or more indices are greater than normal value, malignant neoplasm is diagnosed. 2 or less more indices are greater than normal value, basophil, monocytes, lymphocytes, young leukocytes, hemoglobin, protein contents and erythrocyte sedimentation velocity, color index, circulating blood volume, height and weight are additionally investigated to calculate diagnostic indices. One of the diagnostic indices exceeding the normal value, malignant neoplasm is diagnosed. No indices exceeding the normal values, benign pathology is diagnosed. EFFECT: enhanced accuracy of malignant tumor diagnosis at early stage. 1 dwg , 4 tbl
