What do we know about osteoma cutis? Literature review. Clinical cases

This article summarises the data of epidemiology, etipathogenesis, a clinical picture, diagnosis and the treatment of osteoma cutis. The classification, a histological picture, the place of osteoma cutis from the point of view of the phenotype in relation to the information of the world literature are presented. Osteoma cutis is a rare benign disease characterised by the formation of the bone tissue in the dermis or subcutaneous fat. Two theories of the origin of osteoma cutis are of particular interest: the result of fibroblast metaplasia into osteoblasts or the differentiation of primitive mesenchymal cells into osteoblasts and their migration to an ectopic site. Diagnosis and differential diagnosis are based on the clinical examination, measurement of calcium, parathyroid hormone, x-ray and skin biopsy. The differential diagnosis involves many dermatoses, including ossified hair follicle, osteosarcoma, epidermoid cysts, fibromas, neurofibromas, basal cell carcinoma, etc. The approach to the treatment is to use non-invasive or invasive methods: tretinoin cream, dermabrasion and punch biopsy, YAG laser, scalpel excision, curettage and CO2 laser. We consider skin osteoma to be an underestimated dermatosis, since we have not found descriptions of such cases in reviews in the available Russian literature.

Progressive Primary Plate-Like Osteoma Cutis of the Scalp

Osteoma cutis (OC) or cutaneous ossification refers to uncommon bone formation in the skin. Primary OC develops without any predisposing factor or pre-existing lesion, whereas secondary OC sets out as a dystrophic ossification following traumatic, cicatricial, and neoplastic factors or other cutaneous inflammations. Herein, we report a rare case of long-standing progressive primary OC of the scalp resected in 3 sessions with no recurrence after 1 year.

Osteoma Cutis of the Scalp in a Case of Multiple Basal Cell Carcinoma Induced by Radiotherapy

Introduction: Multiple osteoma cutis is a rare skin disorder characterized by tiny bone fragments deposition in the skin. It is a benign disease, which occurs as primary or secondary forms. Secondary osteoma cutis most commonly appears on the facial acne scars in middleaged women. The exact etiology of this phenomenon is unknown, but it may be induced by osteoblastic metaplasia of mesenchymal elements. Case Presentation: Herein, we report a 70-year-old man with a history of multiple basal cell carcinoma (BCC) of the scalp caused by radiotherapy, who referred to our tumor clinic with multiple skin-colored subcutaneous papules and nodules on his scalp from 2 years ago along with cutaneous side effect changes of radiodermatitis. In the histological examination of lesions with differential diagnosis of BCC, cysts, and adnexal tumors, the diagnosis of osteoma cutis was established without any evidence of BCC. Conclusion: Osteoma cutis is a rare disorder most commonly affecting the face, but our patient had multiple lesions of the scalp. The inflammatory changes of radiodermatitis may be the principal cause of this change.