Sandbox: Kaposi

Macular stage: Thin-walled, angulated vessels throughout dermis, with hemosiderin and plasma cell infiltrate Patch stage: Angulated lumina that dissect dermal collagen Vessels may proliferate around well-developed round venules (premonitory sign) Angiomatoid vascular spaces with red blood cells are surrounded by spindle cells in short fascicles Tumor stage: Solid nodules with extensive spindle cells and red blood cells in slit-like lumina No/rare mitotic activity or atypia Lymphangioma-like variant: Thin, angulated vessels with no red blood cells