Nodular cutaneous amyloidoma of the extremity secondary to chronic granulomatous inflammation in setting of sarcoidosis.

Soft tissue amyloidoma is a rare condition that presents primarily in the abdomen and/or mediastinum and more uncommonly on the extremities. Soft tissue amyloidomas on the extremities have been associated with chronic inflammation, particularly when accompanied by AA-type amyloid deposition as seen in local trauma, surgery, hypertension and diabetes. To our knowledge, this is the first reported case of nodular cutaneous amyloidoma in the setting of systemic and cutaneous sarcoidosis. A 65-year-old woman presented with an asymptomatic subcutaneous nodule above her left lateral malleolus. Histopathology of the lesion showed an inconspicuous epidermis with amorphous eosinophilic material deposited in masses within the entire dermis. Congo red and crystal violet stains were positive. Based on the clinical and pathologic findings she was diagnosed with nodular cutaneous amyloidoma. We hypothesize that this process developed secondary to the chronic granulomatous inflammation of sarcoidosis.