High YKL-40 protein expression has also been found in carcinoma cells from breast [16-18], colon [2], liver [19], cervix [2], and head/neck [20], and skin (melanoma) [2], as well as within tumor-associated macrophages, mast cells and leukocytes [10,18,20-22]. This evidence concerns the gene CHI3L1 and neoplasm.