About Mastocytosis

I am writing to ask about Mastocytosis. My daughter showed me, last week, a birthmark on my 5 month old granddaughters stomach. It was about the size of a pencil eraser, flat and tannish in color. I did not think it was a birthmark. This morning she called and told me that the birthmark was raised. Jalyn (my granddaughter) already has a hemanigioma around her left nipple so I thought it might be a good idea to  call the pediatrician and make an appt. She called me back to tell me that the Doc has told her that Jalyn has a Mastocytoma and not to worry about it they will reschedule her and give her a little more info. They did tell her that this is hereditary. We have no recollection of either families having this condition. Could it be related to the hemangioma? What does this mean........will she get more tumors or is this solitary? I can't find any answers as to what to expect. Is Mastocytoma (meaning one tumor) the same as Mastocytosis (meaning the condition of mast cells)? I am very confused and can't seem to find the answers on the net! Thanks for any info you might be able to share!!!!!!!!!!!!!!!!   Cyndy