Clinical characteristics and prognosis of immunoglobulin D myeloma in the novel agent era.

Immunoglobulin D (IgD) myeloma is a rare subtype that used to lead to a poor outcome. To investigate the current clinical features, cytogenetic changes and survival of patients with IgD myeloma under novel treatments, we analysed 47 patients with IgD myeloma, 31 men and 16 women, with a median age of 54.5 years. We found that IgD myeloma was associated with higher frequencies of anaemia, renal failure, and hypercalcemia and higher levels of serum LDH compared with non-IgD myeloma. More than 90% of patients with IgD myeloma had at least one cytogenetic abnormality demonstrated by fluorescence in situ hybridisation (FISH). IGH translocations were the most common abnormalities, which were mainly caused by t(11;14). Moreover, 36.2% of patients were at the Revised International Staging System (RISS) stage III when diagnosed. Those patients had significantly shorter PFS and OS compared with patients at RISS stages I and II. In conclusion, IgD myeloma has specific clinical characteristics. The RISS grade was shown to be a simple and effective method to predict the prognosis of patients with IgD myeloma.