Cutaneous lymphosarcoma with IgG monoclonal gammopathy, serum hyperviscosity and hypercalcemia in a cat

A diagnosis of cutaneous lymphosarcoma in an 11 year old castrated male Siamese cat was made. In addition to an IgG monoclonal gammopathy, a variety of unusual paraneoplastic syndromes were associated with this tumor. These included serum hyperviscosity, hypercalcemia and increased susceptibility to infection.