This case report provides evidence that Waldenström's macroglobulinemia may cause cutaneous manifestations represented as papules/nodules through the development of light chain amyloidosis. Here, we report a case of a 67-year-old man.

A 67-year-old Japanese man was referred to us with numerous papules and nodules. Examination revealed i) IgM-monoclonal proteinemia, ii) amyloid protein deposition around vessels in the dermis and subcutis, and iii) lymphoplasma cells into bone marrow. This report shows that Waldenström’s macroglobulinemia causes papules/nodules through the development of amyloidosis.