A six-week-old female Hanoverian Scenthound was presented because of a 3 × 4 × 1 cm subcutaneous neoplasm on the left lateral hind limb that was associated with the musculature. The regional lymph node (Ln. popliteus) was not affected. At 2 weeks of age, all puppies had been affected by pyoderma. The puppy was initially treated with Traumeel® (Biologische Heilmittel Heel GmbH, Germany). Two days later, the puppy was presented again as no changes occurred. Pulsation was palpable, and sonography showed an inhomogeneous structure rich in blood vessels. Four weeks after the initial presentation, the mass had grown to 7 × 6 × 1.5 cm and had invaded the surrounding tissue. There was no demarcation to the gastrocnemius muscle and flexor digitalis superficialis muscle and a strong blood supply. The mass and regional lymph node were surgically removed at the owner’s decision. Four days after initial treatment, surgical revision and renewal of vessel ligation were performed due to severe postoperative bleeding in the wound area. Subsequently, wound healing proceeded without complications. At the time of writing (5 months postoperatively) the animal displays no evidence of recurrence and the puppy developed physiologically without loss of performance or physical limitations. The mass and lymph node were sent for histopathologic examination. The samples were processed routinely, and sections were stained with hematoxylin and eosin stain. Immunohistochemistry was performed to detect factor VIII-related antigen (rabbit anti-factor VIII PAP polyclonal, Agilent Technologies®, Waldbronn, Germany; formerly DAKO® Hamburg, Germany), alpha-smooth muscle actin (αSMA; mouse anti-alpha-smooth-muscle-actin ABC monoclonal Agilent Technologies®, Waldbronn, Germany), vimentin (mouse anti-vimentin ABC monoclonal, Agilent Technologies®, Waldbronn, Germany), desmin (mouse anti-desmin ABC monoclonal, Agilent Technologies®, Waldbronn, Germany), pan-cytokeratin (mouse anti-cytokeratin pan ABC monoclonal, OriGene Europe®, Herford, Germany) and melan A (mouse anti-melan A monoclonal, Santa Cruz Biotechnology®, Heidelberg, Germany). Biotinylated horse anti-mouse antibody (Vector Laboratories®, Eching, Germany) and biotinylated pig anti-rabbit antibody (Agilent Technologies®, Waldbronn, Germany) were used as secondary antibodies. Histopathology revealed a multinodular, unencapsulated, well-demarcated, partly infiltrative, moderately cellular subcutaneous mass that replaced subcutaneous adipose tissue and skeletal muscle. The mass consisted of streams and bundles of two populations of cells. One population of plump endothelial cells with a moderate amount of basophilic cytoplasm and a round to oval nucleus with finely stippled chromatin formed slit-shaped vascular channels. The second population consisted of spindle cells with a moderate amount of pale basophilic cytoplasm and oval nuclei with mostly one nucleolus and coarsely clumped chromatin. The spindle cells and a fibrous stroma surrounded the slit vascular channels, occasionally with spindle cells arranged in circular manner around these channels, forming vascular structures. In some areas, the neoplasm consisted only of spindle cells on a fibrous stroma; in others, the spindle cell population was intermingled with the vascular structures or mostly consisted of vascular structures. There was moderate anisocytosis and anisokaryosis. Mitoses were rare in both populations (< 1 mitosis per high power field (HPF) [0,273 cm2]). The tissue was infiltrated with small numbers of lymphocytes, macrophages, and plasma cells. Neutrophilic granulocytes were found in some vascular structures formed by the tumor (not shown). There was mild regeneration of the skeletal musculature. The endothelial cells were positive for factor VIII-related antigen, and a subset of the spindle cells, particularly those encircling slit-like vascular channels, were positive for smooth muscle actin. Both cell populations were positive for vimentin and negative for pan-cytokeratin, desmin and melan A. Follicular hyperplasia, blood resorption and mild sinus histiocytosis were found in the lymph node. The histologic and immunohistological pattern supports the diagnosis of hemangioma. Based on the histological appearance, the neoplasm was classified as a granulation tissue-type hemangioma.