Histological tissue examinations are rarely used to extend the standard clinical lymphological diagnosis. However, new imaging techniques show—more than expected—a more detailed differentiation and classification of previously known entities. A state-of-the-art lymphologic diagnosis will take a concerted approach: Examine the tissue by 3D histology and the larger luminal vessels by MR-lymphangiography, and confirm the findings by molecular diagnostics. With 3D histology, lymphologists have also made progress towards the goal of early detection of the disease and targeted application of the most suitable treatment.