[1050] Calretinin and B72.3 as Useful Markers in the Differential Diagnosis of Adenocarcinoma Versus Reactive Mesothelium in a Background of Adnexal Endometriosis

TR Pal, ZJ Schreiber, J Liu, C Tornos. Stony Brook University Medical Center, Stony Brook, NY

Background: Florid reactive mesothelial hyperplasia can be seen in the ovary or fallopian tube of patients with endometriosis, and can simulate metastatic adenocarcinoma. The cytologic features alone may not be conclusive enough to render an unequivocal diagnosis. Immunohistochemistry can be a useful tool in differentiating between these two entities.
Design: Using our institutional database we identified six cases of ovarian endometriosis associated with florid reactive mesothelial hyperplasia within a period of 24 months. Five of the cases had a proliferation of small tubular structures on the ovarian surface that could have been misinterpreted as metastatic adenocarcinoma. One of the cases had a similar histologic appearance, but the tubular proliferation was in a fallopian tube. Immunostains for Calretinin and B72.3 were performed in all six cases.
Results: In all six cases, positive staining with Calretinin and negative staining with B72.3 confirmed the mesothelial origin of the tubular structures.
Conclusions: Ovarian endometriosis can be associated with florid reactive mesothelial hyperplasia in areas of adnexal endometriosis that can mimic metastatic low grade adenocarcinoma. Immunostains for Calretinin and B72.3 can be a helpful diagnostic adjunct.
Category: Gynecologic

Tuesday, March 10, 2009 1:00 PM

Poster Session IV # 164, Tuesday Afternoon