Juvenile hyaline fibromatosis. A histologic and histochemical study

Histochemical and routine light microscopic studies were performed in nodular skin lesions excised from one patient with juvenile hyaline fibromatosis. The lesions had different times of evolution. Recent lesions showed a high density of fibroblastlike cells embedded in an amorphous matrix of glycoproteins, hyaluronic acid, and small amounts of chondroitin sulfates A and C and of dermatan sulfate. The progressive enlargement of the lesions was due to an increase in the amount of intercellular matrix produced by the cells that progressively displayed a pattern of peripheral stratification. In the older lesions, the matrix was mainly composed by chondroitin sulfates A and C. We suggest that juvenile hyaline fibromatosis represents a disease of the connective tissue with progressive abnormal differentiation to chondroid tissue.