A 16-year-old white boy developed a solitary lesion on his thigh which, when excised two years later, proved to be urticaria pigmentosa. To the best of our knowledge, this is the third reported case of solitary mastocytoma occurring in an adult.
Baraf CS, Shapiro L. Solitary MastocytomaCase Report in an Adult. Arch Dermatol. 1969;99(5):589-590. doi:10.1001/archderm.1969.01610230081014