CASEA 74-year-old woman presented to a dermatology offi ce with complaints of a painful area on the helix of the right ear. The lesion intermittently heals and recurs and is made worse by sleeping on her right side. She has been sleeping primarily on her right side for over a decade, due to shoulder problems. She denied any recent trauma, cold exposure, sunburn, or additional lesions. She attempted to cure the lesion with triple antibiotic ointment, topical antifungal creams, and tea tree oil, all without success. Her past medical history is remarkable for multiple nonmelanoma skin cancers and actinic keratoses, and she was worried this was a skin cancer "like my husband had on his ear."Physical examination reveals signifi cant photodamage on the face, ears, arms, and upper chest. On the lower crus of the antihelix, exactly where it is overlapped by the root of the helix (Figure 1), she has a 3 mm, fi rm, tender nodule with a 1 mm central ulcer (Figure 2).
THE MOST LIKELY DIAGNOSIS IS • relapsing polychondritis • chondrodermatitis nodularis • squamous cell carcinoma • basal cell carcinoma
DISCUSSIONThe patient's age, history of sleeping on one side, location of the lesion, and clinical appearance all support a diagnosis of chondrodermatitis nodularis (CN). CN is also called chondrodermatitis nodularis chronica helicis et antihelicis, as it is chronic and occurs both on the helix and on the antihelix. Some lesions present with a central crusty core, although it is often excoriated by the patient, leaving only a small ulcer.Squamous cell carcinomas are also commonly painful and present on a sun-damaged ear, so this must be ruled out via a full-thickness biopsy if the diagnosis is in question or a lesion persists despite treatment. Basal cell carcinoma also occurs in sun-damaged skin, and may have central ulceration, but usually is not painful. Relapsing polychondritis also causes a painful red ear, but would not be limited to a small pressure-bearing area. To rule out skin cancer, and for therapeutic benefi t, a deep saucerization shave biopsy was performed. Care was taken to avoid leaving any jagged edges or fragmented cartilage, and the base of the lesion was not curetted.Histopathology revealed irregular epidermal hyperplasia with hyperkeratosis and hypergranulosis, degeneration of the connective tissue beneath the zone of hyperplasia, and a mild infl ammatory infi ltrate of mononuclear cells. Histopathology of CN often includes visualization of a large central crater fi lled with acellular necrotic debris, fi brin, and infl ammatory cells; acanthotic hyperkeratotic epidermis around the crater; fi brin and eosinophilic dermal collagen under the crater; and edema of the surrounding viable dermis. 1 Signs of sun damage often are present, such as telangiectasia, and signs of chronic infl ammation of ear cartilage such as fi brosis and even ossifi cation of cartilage.CN is caused by continuous pressure on the fragile rim of cartilage inside the helix, especially in the setting of thin overlying skin. It is most comm...