Immunolocalization of CD163+ Tumor-Associated Macrophages and Symmetric Proliferation of Ki-67 as Biomarkers to Differentiate New Different Grades of Laryngeal Dysplasia

CD163+ TAMs infiltrating the epithelium and Ki-67 overexpression in the basal layer may serve as biomarkers to differentiate low-grade dysplasia from high-grade dysplasia of the larynx. A symmetric proliferative pattern was observed during laryngeal carcinogenesis following Ki-67 overexpression.

Immunohistochemistry for CD163, Ki-67, and cyclin D1 was performed using paraffin-embedded specimens. CD163+ TAMs infiltrating the epithelium were estimated. Ki-67 and cyclin D1 were evaluated in four parts of the epithelium-basal, parabasal, middle third, and upper third layers.

In total, 133 specimens were analyzed, including low-grade dysplasia (n = 31), high-grade dysplasia (n = 49), carcinoma in situ (n = 23), and normal mucosa (n = 30). CD163+ TAMs infiltrating the epithelium were significantly higher in high-grade dysplasia than in low-grade dysplasia. In the basal layer, Ki-67+ and cyclin D1+ cells were overexpressed in high-grade dysplasia (P < .0001). The area under the curve was 0.958 for Ki-67 and 0.909 for CD163+ TAMs (P < .0001). Conclusions: CD163+ TAMs infiltrating the epithelium and Ki-67 overexpression in the basal layer may serve as biomarkers to differentiate low-grade dysplasia from high-grade dysplasia of the larynx. A symmetric proliferative pattern was observed during laryngeal carcinogenesis following Ki-67 overexpression.