Dystrophic calcinosis cutis is the aberrant deposition of insoluble calcium in cutaneous tissue generally secondary to inflammatory connective tissue disease. Although calcinosis cutis is commonly seen in juvenile dermatomyositis, it is a relatively rare occurrence in adult disease. Herein, we discuss an 82-year-old woman with extensive history of dermatomyositis of the scalp who presented with new-onset calcinosis cutis of the scalp.

Calcinosis cutis, although common in systemic sclerosis, has been rarely reported in patients with morphea. We describe four patients with calcinosis cutis arising within morphea plaques, discuss their treatments and outcomes, and review previously published cases. Current management recommendations for concomitant morphea and dystrophic calcinosis cutis are based on limited data and expert opinion, which has primarily focused on reduction of active inflammation and reduction of symptoms related to calcinosis or ulceration. In most cases, no improvement of calcinosis was noted. The use of intralesional corticosteroids to active lesions in conjunction with systemic treatment, including methotrexate when indicated, appear promising treatments to halt progression of the disease. Surgical excision seems to be the most definitive treatment for calcinosis affecting morphea plaques, but the current literature lacks details regarding disease recurrence following operative management.

Calcinosis cutis results from the deposition of insoluble calcium salts in the skin and subcutaneous tissue. Herein, we report a case of extensive metastatic calcinosis cutis in an 18-year-old woman with stage IV Hodgkin lymphoma with skeletal involvement. With combination therapy including radiation directed at her lymphoma and diltiazem, her lesions improved dramatically. This case demonstrates the previously unreported association between calcinosis cutis and Hodgkin lymphoma.

Idiopathic calcinosis cutis refers to progressive deposition of crystals of calcium phosphate in the skin and other areas of the body, in the absence of any inciting factor. Idiopathic calcinosis cutis may sometimes take the form of small, milia-like lesions. Most commonly, such milia like lesions are seen in the setting of Down syndrome. Herein, we report a 5-year-old girl with multiple asymptomatic discrete milia-like firm papules distributed over the face and extremities. A diagnosis of milia-like idiopathic calcinosis cutis associated with Down Syndrome was provisionally made and was confirmed by histopathology and karyotyping.

Milia-like idiopathic calcinosis cutis (MICC) and subepidermal calcified nodule (SCN) are described as different entities under the heading of idiopathic calcinosis cutis. Although there are some clinical differences, they share many features. Whereas MICC lesions are located mostly on the extremities and rarely on the face, SCN manifests itself mostly on the face, rarely on the extremities. Milia-like idiopathic calcinosis cutis almost always presents with multiple lesions, whereas SCN shows mainly solitary and rarely multiple lesions. Association with Down syndrome (DS) has been reported in up to two-third of the cases with MICC, but not in SCN. We herein present a 5-months-old girl without DS, manifesting a 2mm solitary, white hard papule surrounded by erythema, located on the finger. Histopathologic findings revealed the presence of dermal calcium deposits. When a solitary papular lesion of idiopathic calcinosis is seen in a child, especially if not associated with DS, it is difficult to differentiate MICC from SCN. We believe that these entities may represent variants of the same pathology and it may be more appropriate to designate a solitary lesion as SCN, regardless of its location.

We report an 11-year-old girl who presented with white papules on the dorsal and palmar region of the hands bilaterally. The parents reported that the lesions had appeared four months before and some had resolved spontaneously. The girl was suffering from celiac disease, Down syndrome, and alopecia areata treated with topical corticosteroids. At the first visit, the girl presented with alopecia areata, corticosteroid acne, and a dozen white papules located on the hands. On dermoscopy, a whitish structureless area was seen. Histological examination showed the presence of calcium deposits without tissue damage, thus confirming the diagnosis of milia-like idiopathic calcinosis cutis. At 6-month follow up, the lesions had completely disappeared. Milia-like idiopathic calcinosis cutis is a benign cutaneous disorder consisting of calcium deposits in an apparently undamaged dermis and is typically associated with Down syndrome. Up to a quarter of patients have coexisting syringomas. The milia-like papules tend to self-resolve as patients reach adulthood, so a wait-and-see approach is recommended.

Cutaneous dystrophic calcification as a late change of radiation therapy is a rarely reported finding. Initially, it was almost exclusively described as occurring on the chest wall in breast cancer patients but has since been described in several other malignancies. We describe the first reported case of radiotherapy-induced calcinosis cutis occurring at the site of a previous liposarcoma. Review of the literature including risk factors, similar cases, pathophysiology, and management is also explored.

Subepidermal calcified nodules are an uncommon subtype of idiopathic calcinosis cutis. Morphologically, this entity typically present as a single, well-circumscribed, white-yellow nodule. Based on clinical appearance alone, subepidermal calcified nodules are frequently misdiagnosed and often requires histological confirmation. We describe two cases of subepidermal calcified nodules presenting atypically as cutaneous horns. Subepidermal calcified nodules presenting as a cutaneous horn has rarely been reported; on review, there are fewer than 10 such cases have been described within the past 30 years. The cases described here illustrate the clinical variety and should increase awareness of subepidermal calcified nodules presented.