Background: Impaired cellular immunity appears to be a risk factor for progression of cervical neoplasia, but the immunobiology of neoplastic progression is poorly understood. The objective of this study was to characterize the subpopulations of T lymphocytes that infiltrate various grades of cervical neoplasia including metaplasia to invasive cancer in immunocompetent women.
Method: In 65 patients with a spectrum of cervical disease ranging from normal cytology to carcinoma, the relative proportions of total T lymphocytes and CD4- or CD8-expressing (helper or cytotoxic) T lymphocyte subsets were determined by immunohistochemistry.
Results: When the invasive carcinoma stromal infiltrate was compared with the infiltrate of preinvasive lesions, the numbers of total T cells and the CD8-positive subset increased significantly in the invasive cancers (P < 0.005). Although immunocyte infiltrates were highly concentrated in focal clusters beneath the preinvasive squamous lesions, the CD8-positive immunocytes diffusely infiltrated the invading tumor.
Conclusions: The CD8-positive T cell infiltrate far exceeded the CD4-positive cells in the invasive, but not in the preinvasive lesions, a finding that suggests that CD8 cells are recruited preferentially to cervical lesions with progression to invasion.