CARDIAC AMYLOIDOMA WITH IGM-KAPPA GAMMOPATHY

A 73-year-old man presented with dyspnea and atrial flutter associated with an amyloid tumor in the heart. IgM-kappa gammopathy, hypercalcem ia, and extensive cardiac and mediastinal invasion suggested a maligna nt lymphoid or plasma cell process. Although amyloidoma is generally c onsidered to be a benign tumor, the aggressive features of this case m andated chemotherapy because the critical location rendered the tumor inoperable. This case provides noteworthy evidence in support of a pos sible pathogenic relationship between amyloidoma and plasmacytoma by v irtue of dual representative features: localized amyloid infiltrated w ith plasma cells and the associated gammopathy. Local and systemic mal ignant features lend additional support to this hypothesis.