Dermatomyositis and Metastatic Lung Adenocarcinoma First Presenting as Calcinosis Cutis

Grace Liao Lee, DPT; Georgann Anetakis Poulos, MD, RPh; Matthew J. Zirwas, MD

Drs. Lee and Zirwas are from Wright State University Boonshoft School of Medicine, Dayton, Ohio; Dr. Poulos is from the Division of Dermatology, The Ohio State University, Columbus, Ohio

Disclosure: The authors report no relevant conflicts of interest.

Abstract
Calcinosis cutis is a rare complication of adult dermatomyositis. The authors report a case of dystrophic calcinosis cutis that ultimately led to the diagnosis of dermatomyositis and metastatic lung adenocarcinoma.
(J Clin Aesthet Dermatol. 2012;5(1):47–48.)

A 51-year-old woman with a history of hidradenitis suppurativa and type 2 diabetes mellitus presented to the dermatology clinic due to a two-month history of a finger nodule. She denied associated pain and drainage. Review of systems was negative other than occasional fatigue.

On physical examination, a 1cm firm dermal nodule was palpated on the left distal phalanx (Figure 1). In addition, violaceous patches were noted in a periocular distribution along with significant eyelid edema (Figure 2). Initial workup, including a pelvic ultrasound, revealed an ovarian teratoma. Laboratory assessment was significant for an antinuclear antibody (ANA) of 1:1280 with a diffuse and nucleolar pattern. Chest computed tomography (CT) showed a 4.2×4.1×6.5cm right upper lobe lung mass (Figure 3). Biopsy led to the diagnosis of primary lung adenocarcinoma. Subsequent brain magnetic resonance imaging (MRI) revealed multiple enhancing lesions throughout the brain parenchyma representing metastases (Figure 4).

The authors’ patient underwent three cycles of carboplatin and pemetrexed and whole brain radiotherapy (3750cGy in 15 fractions) with progression of the brain metastases. The patient was placed in hospice care 11 months after presenting to the dermatology clinic with calcinosis cutis (CC). She unfortunately succumbed to her disease shortly thereafter.

Discussion
Calcinosis cutis is a condition involving the deposition of insoluble calcium salts in the skin. It is classified into four etiological categories: dystrophic, metastatic, idiopathic, and iatrogenic.[1]

Dystrophic CC is typically found in association with connective tissue disease.[2] Dystrophic CC is a relatively common complication in juvenile dermatomyositis; however, it is relatively rare in adults with dermatomyositis.[3] Dystrophic CC occurs when calcium deposits in damaged or inflamed connective tissue in the setting of normal calcium and phosphate metabolism.[4] The exact underlying mechanism of CC is unknown. However, a current theory suggests the release of calcium from mitochondria of the damaged muscle cells promotes mineralization.[5] Alternatively, inorganic ions, abnormal collagen, elastin, or subcutaneous fat at the site of tissue damage may serve as a nidus for dystrophic calcification.[6] In adults, the cutaneous lesions of CC often present as firm dermal or subcutaneous papules or nodules around sites susceptible to repetitive trauma, such as elbows, knees, buttocks, and hands.[4] Complications of dystrophic calcification include pain, cosmetic disfigurement, ulceration with infection, impaired activities of daily living, and mechanical compromise.[4] Because CC has an insidious onset, early diagnosis frequently evades the clinician. In children, delayed diagnosis of dermatomyositis may increase the risk of developing CC.[2,7]

Effective treatment of dystrophic CC has not been studied in controlled clinical trials. However, there are reports suggesting potential benefits of agents including bisphosphonates, probenecid, low-dose warfarin, aluminum hydroxide, colchicine, and diltiazem.[1,5] There are also few cases of spontaneous regression of the calcinosis.[5,6]

In the patient described in this case, further investigation into the etiology of the CC ultimately led to the discovery of metastatic adenocarcinoma of lung primary. This unfortunate patient serves as another reminder of the importance of complete skin examination and thorough workup when the diagnosis of dermatomyositis and/or CC is suspected.

References
1.    Moss J, Syrengelas A, Antaya R, Lazova R. Calcinosis cutis: a complication of intravenous administration of calcium gluconate. J Cutan Pathol. 2006;33(Suppl 2):60–62.
2.    Weinel S, Callen JP. Calcinosis cutis complicating adult-onset dermatomyositis. Arch Dermatol. 2004;140:365–366.
3.    Abdallah-Lotf M, Grasland A, Vinceneux P, Sigal-Grinberg M. Regression of cutis calcinosis with diltiazem in adult dermatomyositis. Eur J Dermatol. 2005;15(2):102–104.
4.    Lobo IMM, Machado S, Teixeira M, Selores. Calcinosis cutis: a rare feature of adult dermatomyositis. Dermatology Online Journal. 2008;14(1):10.
5.    Kavala M, Sudogan S, Can B, et al. An extremely severe case of cutaneous calcinosis complicating adult dermatomyositis. Clin Exp Dermatol. 2008;34:115–116.
6.    Tristano AG, Vilarroel JL, Rodriguez MA, Millan A. Calcinosis cutis universalis in a patient with systemic lupus erythematosus. Clin Rheumatol. 2005;25:70–74.
7.    Callen JP. Collagen vascular disease. J Am Acad Dermatol. 2004;51:427–439.