Two cases of secondary cutaneous ossification arising in lower abdominal keloids

Abstract

Cutaneous ossification is a rare, benign dermatological condition where bone forms in the dermis or subcutaneous tissue. It is classified as primary when it emerges without a pre-existing condition and secondary when it associates with an underlying condition such as trauma, scars, inflammation, and neoplastic disease. The secondary form accounts for most cases of cutaneous ossification. The pathogenesis of cutaneous ossification is not clear. Keloids are benign fibroproliferative skin disorders that are characterized by chronic inflammation. Their pathogenesis is also not fully understood. We report two cases of secondary ossification arising in postoperative lower abdominal keloids and review the literature on secondary ossification of the skin. We speculate that the intense chronic inflammation in keloids may drive the osteoblastic transformation of either mesenchymal stem cells, endothelial cells, or fibroblasts in the keloids.