Expression of immunohistochemical markers for testicular carcinoma in situ by normal human fetal germ cells.

Abstract

The expression of adult carcinoma in situ markers in normal fetal germ cells is consistent with the hypothesis that CIS cells may arise from fetal germ cells, although re-expression of the antigens in postnatally arising CIS cells could provide an alternative explanation. However, we speculate that a transformation of normal fetal germ cells into CIS cells may take place before the end of the 9th week of fetal development. Furthermore, the expression of c-kit in early human fetal germ cells indicates that the c-kit and its ligand play a role in the early human testicular development.