title: NK cell density in malignant skin tumours--a stereological study.
abstract: We determined the density of natural killer (NK) cells in frozen sections of malignant melanoma (nine cases), squamous cell carcinoma (six cases) and non-neoplastic tonsil (five cases) by immunohistological and stereological methods. The mean density of NK cells in malignant melanoma (5.0 +/- 1.5 X 10(3)/mm3) and in squamous cell carcinoma (5.1 +/- 2.7 X 10(3)/mm3) was significantly lower than in germinal centres of normal human tonsils (5.0 +/- 0.8 X 10(4)/mm3). The NK cell/tumour cell ratio (0.03 +/- 0.015 in malignant melanoma and 0.02 +/- 0.015 in squamous cell carcinoma) is 10(2)-10(4) times lower than that commonly used for in vitro assays. The possible role of NK cells in malignant skin tumours should be viewed with caution.
mesh_terms: D001706:Biopsy; D002294:Carcinoma, Squamous Cell / Q000276:immunology / Q000473:pathology*; D002452:Cell Count; D006801:Humans; D007694:Killer Cells, Natural; D008545:Melanoma / Q000276:immunology / Q000473:pathology*; D014066:Palatine Tonsil / Q000473:pathology; D012867:Skin / Q000473:pathology; D012878:Skin Neoplasms / Q000276:immunology / Q000473:pathology*