How do you know if the spot on the brain is a meningioma or melanoma metastasis

[angela d]

My mom is a stage 3a melonoma patient with no recurrences for 3 years.  She is 55 yrs old and appears very healthy and active, no symptoms of anything. She gets annual brain MRI to check for metastasis.  The most recent scan read the following:

Impression:
There is a small extra axial enhancing mass lesion centered at the planum sphenoidale to the left of midline.  It appears to result in at least mass effect on the left optic nerve and probably abuts both optic nerves. It is seen in the region of the orbital apices an dextends to the superior anterior aspect of the sella. It is most consistent with a planum sphenoidale meningioma. It is stable to minimally increased in size when compared to the study from 1 year ago.  It is conceivable though less likely that this represents a metastatic lesion from the patients known melanoma. The lack of significant interval change in teh absence of therapy weighs against metastatic disease.  Further characterization with a dedicated MRI of the orbits with and without Magnevist is recommended..idealy on a high-field strength system.  Current dimenions = 1.3 x 0.4 x 0.3 cm

What will orbital x-ray show? Why is it needed?  Will the scans give confidence that it is not melanoma mets? If it were melanoma metastasis, would there have been more change than noted over the last year?  Would a PET scan pick this up? What are some good questions to ask her oncologist at her appt? What is the likelihood of needing a biopsy?

The same radiologist read this MRI and the one mentioned from a year ago, but the 'year ago' report said unremarkable

[CCF-Neuro-M.D.-CS]

Mengiomas have a fairly characteristic appearance on MRI and are easily identified by radiologists. They have to provide a differential diagnosis on their reports and given the history of melanoma this a 'possibility' but unlikely especially after a year has gone by
Meningiomas are fairly common in the elderly, and are very slow growing (usually), they usually enhance with contrast
Melanoma spread to the brain usually causes multiple parenchymal (that is not attached to the bone, the panum sphenoidale is a bone) that may have hemorrorhage in them (not contrast)
The orbital MRI will show the meningioma in more detail and to what extent it is compressing the optic nerve. A PET scan would probably not be useful if there is no lesion on MRI to correlate with
Good luck

[angela d]

This is my first time to this website.  Thank you for passing along the helpful website that you found.

I have not studied much related to the brain, just mostly things directly related to melanoma.  It is so scarry.

I am hoping that a Dr. also responds to help give me ideas as to what I should ask the Oncologist / Neurologist....

[hopein2005]

HI, I am sorry to hear your mom is not well,i  found a site for you i am not sure if it will be of any help but it is worth a try { www.cancerbacup.org } click on meningioma or any other helpful info they may have . God bless

[hopein2005]

welcome to the site angela ,I am sure the doctor will reply soon they are fast in responding to the patients on this site . and i am sure a lot of people who come here fill they are God sent.i am a little scared myself they changed my monotoring date for seizures so they can pin point the location for surgery. they called me today and want me come in tomorrow at 11:am. they fill they can do surgery to correct the seizures sense the meds don't work, so i see it will start moving fast foward from this point. back to your mom, i do fill if they found something on last years mri they should have informed her instead of saying it was unremarkable . rather they found it important at the time or not, i am sure it was to you and your mother considering how much you two have been through already . i pray everything goes well from this point it sounds like your mom could use a brake . god bless and keep faith