Lump Near Head, Tingling Sensation, Numbness. What Are Treatment Options?

hi, My friend has a lump, size about 1inch and slowing growing....the area is on left side of head about 2inches behind his ear, although it does not hurt he experiences tingling sensations and numbness.....the lump is also moveable and although hard the surface is kind of spungy, the lump came there approximately 4yrs ago and was about 1/2inch....basically it doubled in size in a matter of 24months.....when the tingling sensation occurs this is when he gets numbness around the lump, these symptoms do not occur every day. thank, Bonnie