Cutaneous manifestations of multiple myeloma and other plasma cell proliferative disorders.

Plasma cell proliferative disorders cause rare but extremely varied dermatologic manifestations that may occur as an accompaniment to established diagnoses, or may be a first clue of an underlying neoplasm in the setting of clinical suspicion. In some instances skin lesions result from aggregation of misfolded monoclonal immunoglobulins or their fragments, as in light chain-related systemic amyloidosis. On other occasions the cutaneous lesions result from deposits of malignant plasma cells or monoclonal proteins. In still others, the dermatologic manifestations are related to antibody activity of monoclonal protein, as in many cases of cryoglobulinemia. This report provides insights into the well-recognized cutaneous manifestations associated with plasma cell disorders.