Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) multiple familial trichoepithelioma ?
    ### Response:
    Multiple familial trichoepithelioma is a condition involving multiple skin tumors that develop from structures associated with the skin (skin appendages), such as hair follicles and sweat glands. People with multiple familial trichoepithelioma typically develop large numbers of smooth, round tumors called trichoepitheliomas, which arise from hair follicles.
    