Lipomas are benign soft tissue tumours composed of mature adipocytes. Lipomas are the most common mesenchymal tumour in adults and are most common between the ages of 40 and 60 years. 5% of patients have multiple lipomas.
Lipomas typically occur in the subcutaneous soft tissues, but can also present in deeper locations, for example within or between muscles, or on the surface of bones.
Lipomas usually present as a painless soft tissue mass. On histological examination they can contain bone (osteolipoma), cartilage (chondrolipoma) or fibrous tissue (fibrolipoma). Deep intramuscular lipomas often encase muscle fibres – this can be seen on MRI scanning and these tumours have a higher rate of local recurrence.
Angiolipoma is a lipoma variant containing small capillary walled vessels. 5% of cases are inherited as an autosomal dominant. These usually present as tender subcutaneous masses. Angiolipomas are always benign and show no tendency to recur.
1. WHO Classification of Tumours of Soft Tissue and Bone, 4th Edition.
Information for patients: