Hi, thanks for writing to HCM.
The bony outgrowth from the outer cortex
of skull need to be determined whether it is a benign growth or malignant. For this to confirm, the biopsied specimen has to be sent for Histopathological examination to define its diagnosis and nature.
A few swellings tend to recur at the same time after removal.
So it always worth going for a biopsy
before a plastic surgical procedure.
Hope this helps