Subepidermal Calcified Nodule in a Child With Neurofibromatosis Type 1

Abstract

Calcinosis cutis (CC) is characterized by calcium deposition in the subcutaneous tissues. Subepidermal calcified nodule (SCN) is a variant of idiopathic calcinosis most commonly seen in the head and neck region of children and adolescents as a single, small, painless, yellow-white papule. A 13-year-old boy with a medical history of neurofibromatosis type 1 (NF1) presented with a firm 0.3 cm white papule in the lower eyelid. He also had neurofibromas of the left forearm and spinal cord, and a malignant peripheral nerve sheath tumor of the right forearm. The eyelid lesion showed hyperkeratotic epidermis, papillomatosis, and elongated rete ridges, with a radial arrangement at the periphery of the well-circumscribed lesion comprising many dystrophic calcifications, histiocytes, and foreign body giant cell reactions. To our knowledge, this is the first case of SCN reported in the context of NF1 or any other systemic disease in the English literature. Although a coincidence is likely, rare observations of the parathyroid gland and calcium metabolism disorders in association with NF1 may provide an explanation that requires further investigation.

Mobile Subcutaneous Calcinosis Cutis: A Case Report of a Mobile Solitary Subepidermal Calcified Nodule on a Woman’s Leg and a Review of Mobile Subcutaneous Tumors

“…The differential diagnosis of benign mobile subcutaneous tumors is summarized in Table 2 [5][6][7][8][9][10][11][12][13][14]. It not only includes neoplasms derived from calcification but also tumors originating from adnexal structures such as hair follicles and adipose tissue.…”

“…Most of the patients (82%) had a single lesion [ 13 ]. Recently, a solitary lesion of subepidermal calcinosis has been described in the lower eyelid of a 13-year-old boy with neurofibromatosis type 1 [ 14 ].…”

“…Often a histiocytic reaction to the dermal deposits is also present. Indeed, chronic inflammation and foreign body giant cell reactions are prominent in children and adolescents; in contrast, these pathologic changes may be mild or absent in adults [ 1 , 14 ].…”

“…They can be derived from adipose tissue, adnexal structures, or calcium. These benign neoplasms can be manipulated to travel from one area to another [5][6][7][8][9][10][11][12][13][14].…”

Multiple subepidermal calcified nodule confined to café‐au‐lait spots

“…LETTER TO THE EDITOR hair follicle nevus in which SCN was surrounded by numerous sweat glands and sebaceous glands. 3 A case of NF1 with SCN not confined to CALs has also been reported, 5 whereas multiple SCN localized to segmental CALs in our case. segmental CALs were noted in segmental NF1 and McCune-Albright syndrome, the pigmented spots in our case may be characteristic of these diseases.…”