Massive lymphomatous nail involvement in Sézary syndrome.

The case of a 65-year-old man affected by chronic erythroderma due to Sézary syndrome and massive lymphomatous infiltration of the nails is reported. The clinical features of the nail lesions, consisting in thickening and discoloration of the nail plates, were not diagnostic. The nail biopsy showed a typical epidermotropic T cell lymphomatous involvement of all the nail constituents. Immunohistochemical characterization of the nails and skin lymphomatous infiltration showed identical results, confirming the neoplastic etiology of both the chronic erythroderma and the nail dystrophy.