Role of intratumoral lymphatic vessel density in the differential diagnosis between primary and secondary mucinous ovarian tumors

• Grant number: 12/11833-0
• Support type: Regular Research Grants
• Duration: December 01, 2012 - November 30, 2013
• Field of knowledge: Health Sciences - Medicine - Pathological Anatomy and Clinical Pathology
• Principal researcher: Filomena Marino Carvalho
• Grantee: Filomena Marino Carvalho
• Home Institution: Faculdade de Medicina (FM). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Mucinous ovarian tumors present difficulties regarding characterization of primary site, and many of them, even those with borderline morphology, correspond in fact to secondary neoplasia. The morphologic criteria, even associated to immunohistochemical markers, as the coordinated expression of cytokeratins 7 and 20, are far from the resolution of this dilemma. The ovarian carcinomas, including the mucinous type, present an active stromal component, particularly in Krukenberg tumors, indicating an active participation of microenvironment in tumor growth. Sanguineous and lymphatic vessels are important components of stroma, and the presence of vascular emboli is more frequent among secondary tumors. Considering these facts, it is possible that the intratumoral lymphatic vascular density (LVD) is distinct in primary and secondary tumors. As this feature has not been investigated in these tumors, we decided to evaluate its role in differential diagnosis between primary and secondary tumors. The study will be retrospective with evaluation of classical morphological features in histological samples of borderline and malignant mucinous ovarian tumors, both primary and secondary. Representative areas of the tumors will be selected for construction of tissue microarrays. Histological sections will be submitted to immunohistochemical staining using antibodies against the common markers often used in the characterization of mucinous tumors (citokeratins 7 and 20, CEA, MUC2, MUC5A, CDX2, p16) and against podoplanin (clone D2-40), a marker for lymphatic vessels. The LVD will be assessed in the intratumoral stromal by counting the number of immunostained lymphatic vessels in 10 hot spot areas at 400X microscopic magnification. The LVD will be expressed by the mean number of vessels in these 10 hot spot microscopic fields. The LVD will be compared in primary and secondary tumors. We next will investigate the association of LVD with the other immunohistochemical markers. (AU)