Proliferation state of lymphatic vessels. Examples of podoplanin positive (green) proliferative (ki-67 positive, red) lymphatic vessels in an oropharyngeal (A-D and I-L) and a supraglottic carcinoma (E-H). D2-40 positive (green) proliferating tumour mass inside a lymphatic vessel of a supraglottic carcinoma (M-P) (lymphatic invasion positive case, ki-67 positive embolus, red). First and second columns D2-40 -green- and ki-67 -red- immunstainings, respectively; third and last columns, DAPI (blue) and merged images. Scale bar, 10 μm.