[1091] Prognostic Significance of Endoglin (CD105) as Angiogenic Marker in Endometrial Carcinosarcoma

A Uihlein, N Ismiil, S Nofech-Mozes, MA Khalifa, JF Silverman, V Dube, RS Saad. Allegheny General Hospital, Pittsburgh, PA; Sunnybrook Health Science Center/Univ of Toronto, Toronto, ON, Canada

Background: Carcinosarcoma of the uterus is a highly aggressive tumor with both malignant epithelial and mesenchymal components. Endoglin (CD105), a member of transforming growth factor beta1 receptor complex, has been shown to be a more useful marker than panendothelial markers such as CD31 in identifying tumor angiogenesis. We investigated microvessel density measured by endoglin as possible prognostic marker in uterine carcinosarcoma.
Design: Surgical specimens from 45 consecutive patients with uterine carcinosarcoma treated with total abdominal hysterectomy and surgical staging were reviewed. Selected tumor blocks with both carcinomatous and sarcomatous components were immunostained for endoglin and CD31. Positively stained microvessels (MV) were counted in densely vascular foci (hot spots) at x400 field in each specimen (=0.17 mm²) by 2 pathologists. Microvessel counts in carcinomatous and sarcomatous components were reported separately. Results were expressed as the highest number of MV count identified within any single field and correlated with other prognostic parameters and survival.
Results: Endoglin identified MV in carcinomatous component in all cases (mean 25+9) and sarcomatous component in 20/45 (44%, mean 5+4). CD31 MV showed staining 44/45 in carcinomatous component (mean 41+14) and 26/45 (58%) in sarcomatous component (mean 10+7). Endoglin only stained proliferating MV in the tumour, while blood vessels in normal tissue were negative. Both CD31 and endoglin MV showed significant correlation with tumor stage, depth of myometrial invasion and cervical involvement (r=0.44 and 0.39; 0.40 and 0.43; 0.38 and 0.36; respectively, P<0.05). They also showed significant correlation with overall survival (log rank P< 0.05). Endoglin MV showed significant correlation with involvement of lower uterine segment, presence of lymphovascular invasion and distance metastases (r=0.47, 0.44, 0.41; respectively).
Conclusions: Our results support that carcinomatous component plays the major role in the progression and behavior of uterine carcinosarcoma. By staining the proliferating MV, endoglin is a specific and sensitive marker for tumour angiogenesis. It has prognostic significance, with positive correlation with tumor stage, angiolymphatic invasion, lymph node and distant metastases and overall survival.
Category: Gynecologic

Wednesday, March 11, 2009 1:00 PM

Poster Session VI # 161, Wednesday Afternoon