The value of multiphasic automated laboratory tests in differentiating stages of malignancy and in detecting recurrence of cancer was studied. Chemical SMA-12 tests (including calcium, phosphate, glucose, BUN, uric acid, cholesterol, total protein, albumin, total bilirubin, alkaline phosphatase (AP), lactic dehydrogenase (LDH) and SGOT) and hematological SMA-4 tests (including hematocrit, hemoglobin, WBC and RBC counts) were performed in 1,578 patients. Baseline data obtained from 582 patients with benign, and 996 patients with malignant, lesions were subdivided according to age, sex, primary site, and extent of cancer. With advancing stages of cancer, there was a significant increase of AP and LDH, but decrease of albumin and hemoglobin. Among patients who had sequential tests, there was a significant decrease of uric acid and LDH with control of cancer, and increase of AP with development of distant dissemination.