The lymphatic circulation is still a somewhat forgotten part of the circulatory system. Despite this, novel insights in lymph angiogenesis in health and disease, application of immune markers for lymphatic growth and differentiation and also the introduction of new imaging techniques to visualize the lymphatic circulation have improved our understanding of lymphatic function in both health and disease, especially in the last decade. These achievements yield better understanding of the various manifestations of lymph oedemas and malformations, and also the patterns of lymphovascular spread of cancers. Immune markers that recognize lymphatic endothelium antigens, such as podoplanin, LYVE-1 and Prox-1, can be successfully applied in diagnostic pathology and have revealed (at least partial) lymphatic differentiation in many types of vascular lesions.Electronic supplementary materialThe online version of this article (doi:10.1007/s00428-016-1945-6) contains supplementary material, which is available to authorized users.

Recognition of microvascular proliferation as a not uncommon feature, congenital arteriovenous malformations provide new insight into the growth behaviour and vascular composition of these lesions.

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Cardiac allograft vasculopathy is regarded as a progressive and diffuse intimal hyperplastic lesion of arteries and veins that leads to insidious vessel narrowing and to allograft ischemic disease, such as acute myocardial infarction or sudden cardiac death. The coronary lesions in transplanted hearts are considered as a particular type of arteriosclerosis with many similarities but also significant differences compared to native coronary atherosclerosis. It is particularly difficult for pathologists to systematically classify the lesions and to elucidate their origins, since over time, the allograft immune responses cause vascular pathology characterized by not only the onset of de novo fibrocellular lesions but also remodeling of already-existing native atherosclerotic lesions in the donor heart. Intraplaque hemorrhages, which result from newly formed leaky microvessels, may cause rapid increase of stenosis and generate a substrate for plaque destabilization. Comparing cardiac allograft vasculopathy from explanted hearts at autopsy with native coronary atherosclerosis from hearts removed at transplantation has revealed that ongoing intraplaque hemorrhages are also an important feature of cardiac allograft vasculopathy and may be important factors in the rapid progression of cardiac allograft vasculopathy.