Are cerebral hemorrhages cancerous?

Hi doctor,

I have been having neuro issues such as seizures, headaches, etc., for the past 2.5 years. I was tested for paraneoplastic syndrome and came up as reactive on immunofluorescence but negative ultimately on Western blot. Still, a PET scan was done, and it was clear.

I have had several brain MRIs over the past 2.5 years. All have noted cerebral microhemorrhages. These are unexplained. I understand that they have not changed in size or character over the years, but one or two more have appeared. I understand the differential diagnosis for these bleeds is hemorrhagic metastatic melanoma. No doctor has suggested it.

What is the possibility that these are actually melanomas? My doctor said unlikely because it has been 2.5 years and the actual hemorrhages remain unchanged. How can a radiologist be sure that these are not cancerous? The first scan done before two and a half years was with contrast, and the remaining were without contrast. I am just concerned about these unexplained hemorrhages in light of my neuro symptoms. I wonder if I have brain metastasis without cancer anywhere else in my body.

Please explain.