Liposarcoma

A liposarcoma is a malignant tumour of fat cells. They are most commonly found in the extremities; in the retroperitoneum; and less often in the head and neck area. Whilst liposarcomas are the most common soft tissue sarcomas in adults, their primary occurrence in the skin (cutaneous liposarcoma) is rare.

This chapter is set out as follows: 

The cause is unknown, however:

• There are six sub-types including well-differentiated, myxoid and pleomorphic

• In general, tumours are most likely to arise from deep-seated, well-vascularised structures rather than from submucosal or subcutaneous fat

• The development of a liposarcoma from a pre-existing benign lipoma is rare

Cutaneous liposarcoma

• Tend to present as rapidly expanding lesions, growing in an exophytic manner, as either dome-shaped or polypoid lesions
• The tumour is centered in the dermis, and it has a minimal tendency to grow downward into the underlying subcutaneous adipose tissue

Non-cutaneous liposarcoma

• The typical presentation is that of a slowly enlarging, painless, submucosal mass in a middle-aged person
• Sometimes lesions can grow rapidly
• Most patients with liposarcoma have no symptoms until the tumour is large and impinges on neighboring structures, causing tenderness, pain, or functional disturbances. In the retroperitoneal area, where liposarcoma is detected at a late stage, the tumour may grow to a substantial size, weighing several pounds at the time of diagnosis

• Management is in Secondary / Tertiary care - all suspicious lumps of unknown diagnosis should be referred urgently (two-week wait)

• Management is surgical with wide local excision

• The prognosis depends on the sub-type, site and size of lesion at point of treatment