Lipoma is the most common benign soft tissue tumor. Lipomas are most commonly found in subcutaneous fatty tissue. Superficial lipomas lying under the skin are slightly displaceable. They feel soft and do not cause pain. Lipomas can rarely lead to a narrowing of the median arm nerve (median nerve) or the ulnar nerve (ulnar nerve). Lipomas can usually be easily identified by ultrasound. In the case of close proximity to nerves or vessels as well as atypical examination findings, a nuclear spin examination is helpful. A malignant change is very rarely possible. Evidence of this can be found in rapid growth or pain. Malignant liposarcomas tend to affect patients between the ages of 50 and 65.