Figure 1

Immunohistochemical analysis of YKL-40 protein expression in paraffin-sections of different types of ovarian tumor tissue (×40). A positive immunostaining appears as a cytoplasmic, granular brown-colored staining. a: Normal ovarium surface epithelium, no staining; b: borderline serous tumor, no staining; c: borderline mucinous tumor, no staining, d: borderline mucinous tumor, 30% positivity; e: well-differentiated serous adenocarcinoma, 50% positivity; f: well-differentiated mucinous adenocarcinom, no staining; g: moderately differentiated serous adenocarcinoma, 30% positivity; h: moderately differentiated mucinous adenocarcinoma, 40% positivity; i: moderately differentiated clear cell carcinoma, 40% positivity; k: moderately differentiated endometroid adenocarcinoma, 70% positivity; l: moderately differentiated serous adenocarcinoma, 70% positivity; and m: moderately differentiated endometroid adenocarcinoma, 80% positivity.