Solitary mastocytoma question

My child has a solitary mastocytoma diagnosed by a pediatric dermatologist.  The doc seemed to gloss over it and said it would go away in a few years.  But everything I read about this says there is the possibility of danger.

What are the chances that this will :  A. turn malignant  B. prove to be a systemic problem or C. result in anaphylaxis or other severe allergic reaction?

My child seems healthy and doesn't seem to itch but has broken out in hives on a number of occasions, has occasional vomiting and stomach pain, and possibly other symptoms of allergy.  He had a reaction to egg yolk, but his dermatologist said hives would not be related to food.  Isn't that crazy?

Finally, are there pediatric allergists and should I see one related to this problem?  Thanks.

[jagesh50]

Solitary cutaneous mastocytomas are benign not to be mistaken or urticaria pigmentosa.It will resolve with application of topical steroids.Do consult.