It’s common to have growths or tumors on your scalp, but they’re often not cancer. In fact, only about 13% of total skin cancers are on the scalp, usually the less serious “nonmelanoma” cancers like basal cell and squamous cell carcinoma. Talk to your doctor if you have a sore on your head. If it’s cancer, it may be a small, smooth, waxy lump that may bleed or get crusty. But you need to see your doctor to find out.