Brief Answer:
Probably not a serious problem

Detailed Answer:
Hello XXXXXX,

thanks for posting on XXXXXXX

It is most likely a benign skull tumor. Subcutaneous nodules of the scalp are common and usually benign (not cancerous). Most of them are cyst, lipoma, fibroadenoma etc but too might possible be malignant tissue (cancerous).
I totally understand why the general surgeon had to send you to a neurosurgeon as the possibility of any skull or scalp mass infiltrating into the skull and maybe to the brain should always be envisaged. So attempting to excise a mass without being sure of where it is rooted is always a risk that most doctors do not want to take.
I personally send my patients for x-ray and for those who can afford CT scan then perform a biopsy for determination of the type of mass (this is only after I am unsure of my physical findings). Ones I am sure of what I am dealing with, I can then refer the patient to the competent specialist or excise the mass myself.
Given the duration of the mass, I do not think it is something to worry much about. It might be fixed but it does not mean it is malignant or rooted deep into the skull bone but rather could be thick fibrotic tissue with multiple sticky surfaces on the skull. For esthetic reasons, you might have to continue with the process of seeing a neurosurgeon (even if the tumor remains there, I do not think it is going to cause you any more harm).

Hope this helps and wish you the best.
Dr. Nsah

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