Coexistence of diffuse plane normolipaemic xanthoma and amyloidosis in a patient with monoclonal gammopathy

Diffuse plane normolipaemic xanthomatosis (DPNX) is a well-defined clinicopathological entity that characteristically presents with yellow–orange plaques in the periorbital areas, the neck, the upper trunk and the flexural folds. DPNX has been reported in association with lymphoproliferative disorders and, occasionally, with miscellaneous, probably coincidental disorders. A case of DPNX in a patient with an IgGλ monoclonal gammopathy and systemic amyloidosis is reported. Clinical and histopathological findings revealed typical features of DPNX and amyloidosis coexisting in the cutaneous lesions. To our knowledge this is the first reported case showing coexistence of xanthoma and amyloidosis in cutaneous lesions in a patient with a monoclonal gammopathy.