Elevated YKL-40 is reported in many pathological conditions such as cancer, diabetes mellitus, cardiovascular disorders and inflammatory diseases of different aetiologies including, among others: bacterial infections, osteoarthritis, hepatic fibrosis, ulcerative colitis, Crohn’s disease, rheumatoid arthritis, asthma, chronic obstructive pulmonary disease and liver cirrhosis [4, 10–14]. The gene discussed is CHI3L1; the disease is cancer.