Anatomic Pathology: Skin Pathology

• Chondrodermatitis nodularis chronica helicis manifests as a chronic, intermittently crusted, painful or tender nodule found primarily on the upper part of the helix or antihelix of the ear in older individuals. The clinical differential diagnosis often includes basal cell carcinoma and squamous cell carcinoma.

• The pathogenesis is considered to be an attempt at transepidermal elimination of damaged dermal collagen, induced by trauma, pressure, cold, or a complication of dermatoheliosis.

• The characteristic histopathologic examination reveals a central area of ulceration or erosion in the epidermis overlying an area of dermal collagen with variable edema and fibrinoid degeneration. At the margin of central defect, there is variable epidermal acanthosis, telangiectatic vessels, and solar elastosis in the upper dermis.

• Most cases exhibit changes in the perichondrium that are prominent directly beneath the degenerated collagen. These changes include fibrous thickening and mild chronic inflammation. Degenerative changes also may be found in the cartilage, with alterations in its staining quality, patchy hyalinization, and, uncommonly, partial destruction with necrosis.

• The usual treatment of chondrodermatitis nodularis chronica helicis begins with conservative measures to relieve pressure and traumatic insults at the site, such as a specially designed pillow to avoid trauma while sleeping. Topical and intralesional steroid treatment and cryotherapy also are used often. For refractory cases, surgical modalities are employed.