Carbonic Anhydrase Type IX Expression in Lobular Endocervical Glandular Hyperplasia and Related Adenocarcinoma of the Uterine Cervix
Yoshiki Mikami, Sachiko Minamiguchi, Norihiro Teramoto, Michikazu Nagura, Hironori Haga, Ikuo Konishi. Kyoto University Graduate School of Medical Science, Kyoto, Japan; Shikoku Cancer Center, Matsuyama, Ehime, Japan
Background: Recent studies have demonstrated that carbonic anhydrase type IX (CA-IX) is a promising bio-marker for early detection of endocervical adenocarcinoma in cases of atypical glandular cells (AGC) on cytology. For the purpose of a triage of AGC cases, CA-IX appears to be a superior to HPV DNA testing and/or p16 cytochemistry since a subset of endocervical adenocarcinomas are high-risk HPV-independent as represented by gastric-type adenocarcinoma of the cervix.
Design: Cases of lobular endocervical glandular hyperplasia (LEGH) (n=10), atypical LEGH (ALEGH) (n=6), and endocervical adenocarcinomas, including usual-type (n=3) and gastric-type (n=7, including 3 minimal deviation adenocarcinomas) were retrieved from the file. Using representative sections of the lesion, expression status of CA-IX was determined immunohistochemically, employing anti-CA-IX antibody (Abcam, MA, USA). Proportion of positive areas and staining intensity, ranging from 0 to 3+, were evaluated.
Results: All 10 adenocarcinomas, including both usual and gastric-types, were positive for CA-IX, with 7 of 10 cases showing 3+ staining, and 6 cases showing positive areas exceeding 50% (3 cases; 100%, 1 case; 80%, 2 cases; 60%). Two adenocarcinomas showed only 30% areas with 2+ positivity, and one showing only 5% areas of 1+ staining. All 10 LEGH without atypia were positive for CA-IX, with all cases showing 50% or more positive areas, although only one case showing 3+ positivity, whereas 5 and 4 cases were 1+ and 2+ intensity, respectively. Five of 6 atypical LEGH were positive for CA-IX, with 4 cases showing 3+ positivity in 100% of areas. Normal endocervical glands, tunnel clusters, and non-specific endocervical glandular hyperplasias were negative for CA-IX, although reserve cell population was positive for CA-IX.
Conclusions: CA-IX appears to be a promising marker for the detection of gastric-type adenocarcinoma and ALEGH, and might play a crucial role in the HPV-unrelated pathway of carcinogenesis, as represented by LEGH-gastric-type adenocarcinoma sequence. From the point of view for practical use of this particular marker, it should be emphasized that; (1) CA-IX staining is rather heterogeneous in cases of adenocarcinoma, and (2) LEGH and ALEGH are also CA-IX-positive, and therefore, results of the staining should be combined with morphology.
Category: Gynecologic & Obstetrics
Tuesday, March 20, 2012 9:30 AM
Poster Session III # 169, Tuesday Morning