Cutaneous Osteomas: A Clinical and Histopathologic Review

Abstract

In 20 000 consecutive skin biopsies we found 35 cutaneous osteomas. Ten were primary while 25 appeared secondary to another abnormality. Associated with ossification were Malherbe's calcifying epithelioma, basal cell carcinoma, nevus cell nevus, appendageal and fibrous proliferations, inflammation, trauma, and calcification. Cutaneous bone formation appears to be either a hamartomatous or metaplastic phenomenon.

Heterotopic bone formation in tumor stromal tissue. Immunohistochemical considerations.

“…In the case of heterotopic ossification, there are no preceding lesions, whereas in metaplastic bone formation, there are preexisting lesions. Examples o£ heterotopic ossification are osteoma cutis (2,11,14), Albright's syndrome ossification (3), calcifying epithelioma Malherbe (16), stromal ossification in tumors of the ovary, kidney and breast (1,(8)(9)(10), and also experimental bone induction in transplanted bladder mucosa (6,12,15).…”

Acral Angioosteoma Cutis

“…We believe that this trauma may have influenced the development of capillary proliferation, and added inflammation or hypoxia may have induced BMP expression. In the reported cases of pyogenic granuloma with ossification, three of four cases did not mention lobular arrangements of capillary proliferation 8,9,11 . Therefore, there is a possibility that some of those cases may have actually been cases of acral angioosteoma cutis.…”

“…However, the pathogenesis of metaplastic ossification has not been explored. There have been four documented cases of ectopic bone formation in cutaneous pyogenic granulomas to date [8][9][10][11] . Vascular endothelial growth factor (VEGF) and bone morphogenetic proteins (BMPs) may play a role in ectopic bone formation in pyogenic granuloma.…”

A Case of Intradermal Melanocytic Nevus with Ossification (Nevus of Nanta)

“…Ossification within the skin may occur in a variety of conditions, including pilomatricoma, basal cell carcinoma, appendageal and fibrous proliferation, inflammation and trauma 1,2 . The occurrence of ossification within a melanocytic nevus is an unusual event [3][4][5] .…”