Bump on Scalp

My dad has a bump, about 1.5'' in size in the middle of his scalp. It's raised, but not very much. He says it started very small and has been growing for about 2 years. It looks weird and spongy but is skin colored, maybe a little grey-ish. I only saw it for a second. I have been looking everywhere online to find out what it is,but haven't found anything.
He won't seea doctor unless he knows he needs to, so I'm hoping it's not serious.
My mom thinks it looks like a wart, but I've never seen a wart so I odn't know.

[Rob79]

If it's growing, it's probably some sort of tumor. Your dad should really see a doctor about it, as the tumour might be cancerous.

[caregiver222]

Very interesting. In  a worst case it is a malignant tumor. It is far more likely to be a completely benign growth filled with lymphatic fluid. Sometimes these lumps disappear by being "smashed" with a book by a physician. Don't do this on your own! If it is a wart, it should be treated because warts are mildly contagious, and I'm sure he wouldn't want anyone else to catch this creature. I think it is unlikely to be a malignancy, however it surely requires the attention of an M.D. Tell him he NEEDS to see a doctor. If nothing else, to make sure this is not somthing that can be transmitted to others.

[noslit]

Please view my post concerning wart from dog bite. noslit