Progressive osseous heteroplasia in male patients. Two new case reports.

Progressive osseous heteroplasia is a rare developmental disorder of mesenchymal differentiation characterized by cutaneous osteomas in infancy and by progressive heterotopic intramembranous ossification of skin and deep connective tissue. To date, typical features of the disorder have been reported only in 8 female patients. This report documents progressive osseous heteroplasia in 2 boys and has important implications for the clinical detection and pathogenetic understanding of this rare disorder.