Endocervical microglandular hyperplasia: Colposcopic aspects, physiopathology and differential diagnosis

Endocervical microglandular hyperplasia (MGH) is a reactive type of glandular lesion that may be confused with endocervical adenocarcinoma from the macroscopic and the colposcopic findings, as well as from a histological. Differential diagnosis is very important. Here, we report a case of a 21 years-old women with a challenging differential diagnosis in the colposcopy and a MGH as histological finding.

Ectopic Prostatic Tissue in the Uterine Cervix and Vagina

Prostatic tissue has rarely been described in the lower female genital tract. We describe 6 cases of ectopic prostatic tissue: 5 involving the cervix and 1 the vagina. The latter is the first reported example of benign prostatic tissue in the vagina. The age of the patients ranged from 21 to 65 years; and in all cases, the prostatic tissue was located within the cervical or vaginal stroma without involvement of the surface. In all cases, there were both glandular and squamous elements, which varied in prominence. In some cases, the squamous elements predominated to such an extent that the underlying glandular component was easily overlooked. In the glandular areas, a double cell layer of luminal and basal cells was focally apparent. There was little cytologic atypia or mitotic activity. Immunohistochemically, 3 of 6 cases were positive with prostate specific antigen (PSA) and all 6 cases marked with prostatic acid phosphatase (PSAP). In some of the positive cases, staining was focal. Positive staining with prostatic markers was confined to the glandular elements with no staining of the squamous areas. Immunohistochemical staining with the high molecular weight cytokeratin 34betaE12 highlighted the basal cell layer, which often extended into the center of the cellular islands, reminiscent of basal cell hyperplasia involving the prostate gland. All cases tested were CD10 positive (largely restricted to the basal cell layer), alpha-methylacyl-CoA racemase positive, and p16 negative. Estrogen receptor (ER) and progesterone receptor (PR) were negative in the glandular areas, but ER was positive in the squamous elements in all cases and PR was positive in 1 case. All cases tested were androgen receptor positive and exhibited a low MIB-1 proliferation index with only scattered positive nuclei. The presence of ectopic prostatic tissue in the lower female genital tract may be more common than is appreciated. Once the possibility is considered, the diagnosis is easily confirmed using immunohistochemistry, although staining with prostatic markers may be focal and PSA may be negative. Ectopic prostatic tissue in the lower female genital tract is almost certainly a benign condition, based on the morphology, including the presence of a double cell layer, although follow-up of larger numbers of cases is required. Possible theories of histogenesis include a developmental anomaly, metaplasia of preexisting endocervical glands, and derivation from mesonephric remnants.

Immunohistochemical staining with MIB1, bcl2 and p16 assists in the distinction of cervical glandular intraepithelial neoplasia from tubo-endometrial metaplasia, endometriosis and microglandular hyperplasia

AIMS

Preinvasive endocervical glandular lesions, termed cervical glandular intraepithelial neoplasia, are increasing in incidence. The distinction of cervical glandular intraepithelial neoplasia from benign mimics, especially tubo-endometrial metaplasia, endometriosis and microglandular hyperplasia, can be difficult. This study investigates the value of immunohistochemical staining with MIB1, bcl2 and p16 in the distinction of cervical glandular intraepithelial neoplasia from these benign mimics.

METHODS AND RESULTS

Immunohistochemical staining using the monoclonal antibodies MIB1, bcl2 and p16 was performed on cases of cervical glandular intraepithelial neoplasia (n = 21), tubo-endometrial metaplasia (n = 13), endometriosis (n = 7) and microglandular hyperplasia (n = 14). With tubo-endometrial metaplasia and microglandular hyperplasia staining with MIB1 was either negative or involved <10% of cells, while with cervical glandular intraepithelial neoplasia the majority of cases (86%) exhibited >10% positive cells. Two cases of endometriosis exhibited a MIB1 index of 10-30% while in the other cases <10% cells stained. With bcl2 the cells of microglandular hyperplasia were negative although there was staining of associated reserve cells in 43% of cases. All cases of tubo-endometrial metaplasia except one and all cases of endometriosis stained diffusely positive with bcl2. Cases of cervical glandular intraepithelial neoplasia were negative or exhibited focal staining. With p16 all cases of cervical glandular intraepithelial neoplasia exhibited diffuse strong positivity, generally involving 100% of cells, while all cases of microglandular hyperplasia were negative. Sixty-two percent of cases of tubo-endometrial metaplasia showed focal positivity, the remainder being negative. Cases of tubo-endometrial metaplasia were never diffusely positive with p16. In three cases of endometriosis there was staining of >50% of cells while the other cases were either focally positive or negative.

CONCLUSIONS

A panel of antibodies, comprising MIB1, bcl2 and p16, is a useful adjunct to histology in distinguishing cervical glandular intraepithelial neoplasia from tubo-endometrial metaplasia, endometriosis and microglandular hyperplasia. Cases of cervical glandular intraepithelial neoplasia are diffusely positive for p16 and generally exhibit a high proliferation index with MIB1, while bcl2 is negative or, at most, focally positive. Tubo-endometrial metaplasia and endometriosis are characterized by strong diffuse positivity with bcl2 and a low proliferation index with MIB1 (although occasional cases of endometriosis show moderate proliferative activity). p16 is negative or exhibits focal positivity in tubo-endometrial metaplasia but in endometriosis there may be quite widespread positivity. Microglandular hyperplasia shows a low proliferation index with MIB1 and is negative for bcl2 and p16.