Significance of CD44v6 expression in gynecologic malignancies

Abstract
Variants of CD44 have been proposed to be important in cancer invasion and metastasis. The purpose of this study was to evaluate the diagnostic and prognostic value of CD44v6 expression in gynecologic malignancies. Immunohistochemistry was used to determine the expression of CD44v6 in samples from a series of 65 cases of early cervical cancer, 76 cases of endometrial samples and 57 cases of serous epithelial ovarian tumors. We analyzed the expression of CD44v6 and correlated the findings with clinicopathological factors. In the cervical series, CD44v6 was detected in 60 cases of cervical cancer (92.3%). The immunoreactivity was decreased when stromal invasion reached a depth of more than 5 mm (P < 0.05). However, it was not correlated with other clinicopathological factors. In the endometrial series, CD44v6 was detected in one endometrial hyperplasia (6.7%) and in 24 endometrial cancers (100%), while it was not detected in the proliferative endometrium (P < 0.05). Immunoreactivity was decreased in grade 2 and 3 endometrial cancers compared with grade 1 (P < 0.05). In the ovarian series, CD44v6 was not detected in the benign tumors, but it was detected in four borderline malignancies (27%) and 12 carcinomas (40%). Immunoreactivity was not correlated with clinicopathological factors of ovarian cancer. CD44v6 may be involved in stromal invasion of early squamous cervical carcinomas and in the cellular differentiation of endometrial cancer. In addition, it may be useful for early diagnosis of endometrial cancer.