Orleander, this might be of help:
"As you can imagine, the only way to be sure what kind of lump you have is to have it in front of you and examine it properly.
Nonetheless, I can tell you most skin or subcutaneous (fatty tissue under the skin) lumps are benign. Most common subcutaneous tumors are lipomas and epidermoid or sebaceous cyst.
Lipomas are benign fatty tumors, probably the most common ones in the entire body, and are more frequent in women.
A sebaseous cyst is a closed sac found just under the skin containing grayish-white, pasty or cheesy-looking skin secretions; most often arise from swollen hair follicles, but also skin trauma can induce a cyst to form.
Benign tumors are usually slow growing, painless, and freely movable lumps beneath the skin.
You have to see your doctor if the lump gets hard, is fixed, grows fast or hurts."
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