It occurs from early childhood to adulthood, and presents as slow-growing, pearly white or skin-colored dermal or subcutaneous papules or nodules on the face, scalp, and back, which may be confused clinically with neurofibromatosis.

[3] The World Health Organization in 2020 reclassified the papules and nodules that occur in juvenile hyaline fibromatosis as one of the specific benign types of tumors in the category of fibroblastic and myofibroblastic tumors.

[4] This condition is characterised by abnormal growth of hyalinized fibrous tissue with cutaneous, mucosal, osteoarticular and systemic involvement.

Clinical features include extreme pain at minimal handling in a newborn, gingival hypertrophy, subcutaneous nodules, painful joint stiffness and contractures, muscle weakness and hypotonia.

[6] Argentinian Matías Fernández Burzaco, aged 23, published a book about his experience of the condition, “Formas Propias”.