Skeletal muscle and fibroadipose tissue infiltrated by a proliferation of variably sized, dilated, and thick-walled vascular channels. Several of these vascular spaces contain organizing thrombi and dense calcifications (phleboliths). The endothelial lining is flat and bland. There is no evidence of cytologic atypia, increased mitotic activity, or necrosis. The morphological features, in conjunction with the provided clinical history, support the diagnosis of a benign intramuscular vascular lesion.
Calcified vascular mass within the right masseter muscle, strongly suggestive of an intramuscular hemangioma.
Soft tissue pieces measuring 1.7 x 1.5 x 0.8 cm in aggregate and a separate fatty soft tissue piece measuring 3.5 x 1.5 x 0.8 cm.
Soft tissue, right masseter muscle mass, excision: