Epidemiological considerations in the role of dendritic/Langerhans cells in human cancer.

The roles of dendritic or Langerhans cells in human neoplasia have been studied in animal models and human subjects for some years. Much has already been learned concerning the operative immunological processes, relationships with other components of the reticuloendothelial system, and correlations with genetics and the aging process. Unfortunately, the present requirement for microscopic examination of human tissues to assay these cells greatly limits the types of study which can be under-taken and their scope. Investigations must presently be limited to human cancers occurring in readily accessible sites such as the uterine cervix, urinary bladder and skin. In the future, it is anticipated that new experimental approaches can be developed which permit the measurement of DC/LC activity levels without the need for biopsy specimens, thus greatly enhancing research possibilities in the important arena of biomedical investigation.