Since malignant cells release enzymatically active nagalase which causes a decrease of GC protein-derived macrophage-activating factor levels to promote immunodeficiency in cancer patient, nagalase is a good marker for monitoring the efficacy of cancer therapy.[14] In this case, nagalase test results showed no activities of cancer cells at the third month of adjuvant therapy plus AC. The gene discussed is NAGA; the disease is cancer.