Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Pilomatrixoma ?
    ### Response:
    Pilomatrixoma is a benign (non-cancerous) skin tumor of the hair follicle (structure in the skin that makes hair). They tend to develop in the head and neck area and are usually not associated with any other signs and symptoms (isolated). Rarely, pilomatrixomas can become cancerous (known as a pilomatrix carcinoma).
    