Adenomatoid Tumors of the Female and Male Genital Tracts: A Morphological and Immunohistochemical Study of 34 Cases
AR Sangoi, EJ Schwartz, JK McKenney, RV Rouse, TA Longacre. Stanford University, Stanford, CA
Background: Although adenomatoid tumors (AT) of the female and male genital tracts are well-characterized as mesothelial in origin, a formal immunohistochemical (IHC) study comparing both traditional and newer mesothelial markers has not been previously reported. In addition, the morphologic differences of AT in male and female sites, if any, have not been formally studied.
Design: IHC analysis was performed on 34 AT from the female and male genital tracts with pankeratin (AE1/CAM5.2), WT-1, calretinin, CK5/6, D2-40, and caldesmon. Staining was semiquantitatively scored on one representative section per case as negative (0, <5% cells stained), focally positive (1+, 5-10% cells stained), positive (2+, 10-50% cells stained), or diffusely positive (3+, >50% cells stained), and a mean extent calculated. Staining intensity was scored from 0 to 3+ and a mean intensity calculated. A variety of morphologic features previously described as characteristic of AT were also compared between tumors in the female versus male genital tracts.
Results: IHC results are summarized in Tables 1. All of the AT from both the male (n=7) and female (n=27) genital tract showed the thread-like bridging strand pattern. Lymphoid aggregates were seen in all 7 male AT, but in only 3 of 27 female AT (11%) (p<0.0001). The remaining morphologic features were variably present in AT with no clear sex predilection.
IHC of Adenomatoid tumorsM=membranous, N=nuclear, C=cytoplasmic, ME=mean extent (0-3), MI=mean intensity (0-3)
|AE1/CAM5.2 (M/C)||WT-1 (N)||Calretinin (N)||CK5/6 (C)||D2-40 (M/N)||Caldesmon (N/C)|
|Female genital tract||27/27 (100%)||26/27 (96%)||27/27 (100%)||5/27 (19%)||27/27 (100%)||1/27 (4%)|
|Male genital tract||7/7 (100%)||6/7 (86%)||7/7 (100%)||1/7 (14%)||7/7 (100%)||0/7 (0%)|
Conclusions: While lymphoid aggregates are common in AT of the male genital tract, they are relatively infrequent in the female genital tract. Thread-like bridging strands are consistently present in all AT and remain useful in diagnosis. Of the putative mesothelial markers evaluated in this study, calretinin and D2-40 show a similar immunoprofile and have a higher sensitivity than WT-1 in AT. The low sensitivity of CK5/6 and caldesmon limit their utility in this setting.
Tuesday, March 10, 2009 1:00 PM
Poster Session IV # 165, Tuesday Afternoon