Immunohistochemical demonstration of histiocytes in normal ectocervical epithelium and epithelial lesions of the uterine cervix

The numbers of Langerhans cells and lysozyme-positive macrophages were assessed quantitatively in normal ectocervical epithelium, cervical intraepithelial neoplasia (CIN), microinvasive squamous cell carcinoma (MICA), clinical invasive squamous cell carcinoma (CICA), and koilocytotic atypia using the avidin-biotin-peroxidase complex (ABC) method. The distribution of Langerhans cells was different from that of lysozyme-positive macrophages in that the former were intermingled with the cervical lesion, while the latter were present mainly surrounding the cervical lesion and/or on the edge of the cervical lesion. The numbers of Langerhans cells and lysozyme-positive macrophages in CIN were significantly larger than those in normal ectocervical epithelium and significantly smaller than those in invasive squamous cell carcinoma (MICA + CICA). Langerhans cell number significantly increased as the grade of CIN advanced. In contrast, the number of lysozyme-positive macrophages did not differ significantly between progressive grades of CIN. As for koilocytotic atypia, the numbers of Langerhans cells and lysozyme-positive macrophages in koilocytotic atypia were significantly greater than those in normal ectocervical epithelium but did not differ significantly from those in CIN 1 and CIN 2. With respect to stromal lymphoid infiltration, invasive squamous cell carcinoma with moderate or dense stromal lymphoid infiltration showed significantly greater numbers of Langerhans cells and lysozyme-positive macrophages than that with no or scattered stromal lymphoid infiltration, but such a correlation was not found in CIN.