ABSTRACT

The third type of tissue discussed in this chapter for its responsiveness to retinoid status is the vaginal and cervical epithelia. The cervix is divided into two major areas, the endocervix and the ectocervix. The endocervix is lined by a simple columnar mucus secreting epithelium (Figure 3), and the vagina and the ectocervix are composed of a nonkeratinizing stratified squamous epithelium. The endo-and ectocervical epithelia join at the squamocolumnar junction or transformation zone (Figure 3A), the most common site for carcinoma development. The endocervical epithelium becomes squamous metaplastic under conditions of vitamin A deficiency (Figure 3B).