How useful is the assessment of lymphatic vascular density in oral carcinoma prognosis?

Abstract Background Lymphatic vessels are major routes for metastasis in head and neck squamous cell carcinoma (HNSCC), but lymphatic endothelial cells (LECs) are difficult to recognize in tumor histological sections. D2-40 stains podoplanin, a molecule expressed in LECs, however, the potential prognostic usefulness of this molecule is not completely understood in HNSCC. We aimed to investigate the value of assessing peritumoral and intratumoral lymphatic vessel density (LVD) as prognostic marker for HNSCC. Methods Thirty-one cases of HNSCC were stained for D2-40 and CD31. LVD and blood vessel density (BVD) were assessed by counting positive reactions in 10 hotspot areas at ×200 magnification. Results D2-40 was specific for lymphatic vessels and did not stain blood vascular endothelial cells. LECs showed more tortuous and disorganized structure in intratumoral lymphatic vessels than in peritumoral ones. No statistical differences were observed between peritumoral-LVD and intratumoral-LVD or between peritumoral-BVD and intratumoral-BVD. Tumor D2-40 staining was positively associated with lymphatic vessel invasion (p = 0.011). Conclusion LVD is a powerful marker for HNSCC prognosis. We found significant differences in peritumoral and intratumoral D2-40 immunoreactivity, which could have important implications in future therapeutic strategies and outcome evaluation

A new monoclonal antibody (3A5) that recognises a fixative resistant epitope on tissue macrophages and monocytes.

AIMS--To develop a monoclonal antibody specific for human macrophages in routinely processed material. METHODS--The monoclonal antibody was derived from a mouse popliteal lymph node after subcutaneous immunisation in the footpad with fragments of human spleen depleted of lymphocytes and erythrocytes. RESULTS--3A5 is a monoclonal antibody reactive with macrophages, monocytes, and histiocytes in routinely processed (formalin fixed, paraffin wax embedded) human tissue specimens. Unlike the well known panmacrophage marker KP1 (CD68), neither dendritic cells (interdigitating cells, Langerhans' cells, and microglia) nor myeloid, lymphoid, or epithelial cells stained with 3A5. CONCLUSION--As the staining pattern of 3A5 is restricted, compared with other macrophage markers and the recognised epitope survives common fixation and embedding procedures, 3A5 is a valuable marker for histiocytes and macrophages in routine diagnostic applications