Primary Localized Cutaneous Nodular Amyloidosis of the Feet: A Case Report and Review of the Literature

Primary localized cutaneous nodular amyloidosis (PLCNA) is a rare disorder that manifests as the cutaneous formation of nodules composed of light-chain amyloid. Although the type of amyloid deposit is similar to primary systemic amyloidosis, there seems to be little, if any, crossover between the 2 diseases. Because reports of PLCNA are sparse, there is no established protocol for treating this disease. This case report presents a 42-year-old man with a visually striking presentation of PLCNA on both feet with some of the lesions possibly being secondary to trauma, a rare phenomenon. The lesions had been present for more than 4 years, and there were no signs or symptoms of systemic amyloidosis. The lesions responded well to a combination of complete curettage followed by CO₂ laser ablation. Primary localized cutaneous nodular amyloidosis is rare and difficult to treat, with high rates of recurrence and a concern for progression to systemic amyloidosis. The diagnosis, workup, treatment, and monitoring of PLCNA also are discussed.