Subcutaneous Lipoma

Bornhovd E, Sakrauski AK, Bruhl H, WaUi R, Plewig G, Rocken M. Mmtiple circumscribed subcutaneous lipomas associated with use of human immunodeficiency virus protease inhibitors Br J Dermatol 2000 143(5) 1H3-14. 

Superscripts indicate the number and types of tumors a, subcutaneous lipoma b, axillary lipoma c, subcutaneous fibroma d, astrocytoma e, skin, fibroma f, skin, squamous cell carcinoma g, skin, basal cell carcinoma h, skin, trichoepithelioma i, skin, keratoacanthoma. 

Superficial lipomas typically appear as compressible, palpable soft-tissue masses in the subcutaneous tissue not adherent with the overlying skin. Lipomas have a male and familial predominance and tend to grow in the hack, shoulder and upper arms with a predilection for the extensor surface. They are more common in the fifth and sixth decades. Although lipomas most often present as a solitary... 

Hand lipomas are often large and lobulated. They frequently develop over the palmar aspect of the hand and the thenar eminence, extending with elongated processes among muscles and flexor tendons. The blending of the fat into surrounding subcutaneous or muscular tissue usually results in ill-defined margins. US can easily characterize these lesions based on their echotexture and compressibility. 

Fig. 13.37a,b Intramuscular lipoma of the sartorius muscle, a Transverse 12-5 MHz US image with b CT correlation demonstrates an undefined lobulated hyperechoic mass (arrows) reflecting fatty lobules within the sartorius muscle. Note that the echogenicity of the mass is higher than that of the overlying subcutaneous tissue. In b, compare the affected sartorius (arrow) with the normal contralateral one (arrowhead)... 

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