CHI3L1 and benign prostatic hyperplasia: As a novel inflammatory marker, YKL-40 has been found to be elevated in several inflammatory and neoplastic disease conditions, including atherosclerosis, benign prostatic hyperplasia, diabetes mellitus, osteoarthritis (OA), polymyositis, psoriasis, rheumatoid arthritis, cervical cancer, and primary prostate cancer [11–18].