Lymphangioma involving the mandible: immunohistochemical expressions for the lymphatic proliferation

We report a case of lymphangioma involving oral mucosa and mandible of an elderly female. The surgical and radiological examinations indicated that the lymphangioma was mainly distributed in the labial mucosa tissue, but had gradually extended into the periosteum and intrabony space of mandible. Immunohistochemical staining was also performed using antiseras of alpha-smooth muscle actin (alpha-SMA), von Willebrand factor (vWF), angiogenin, vascular endothelial growth factor (VEGF), and proliferating cell nuclear antigen (PCNA) to elucidate the pathogenetic implications of the intraosseous lymphangioma. The present case of lymphangioma showed strong immunohistochemical reactivity of angiogenin and vWF, while it showed weak reactions of VEGF and PCNA. The immunostaining of alpha-SMA disclosed an abnormally thinned and discontinuous smooth muscle layer in the lymphatics. Both the X-rays and histological examination showed that the lymphangioma lesion was gradually extending into the adjacent osteoporotic marrow space of mandible. Therefore, we believe that the present case of intraosseous lymphangioma, which showed the harmatomatous growth of the lymphatics into the marrow space of mandible, is closely related to osteoporotic changes of old age.