The cause of<unk>  is generally unknown. Risk factors * Monoclonal gammopathy of undetermined significance (MGUS) increases the risk of developing<unk> . MGUS transforms to<unk>  at the rate of 1% to 2% per year, and almost all cases of<unk>  are preceded by MGUS. * Smoldering<unk>  increases the risk of developing<unk> . Individuals diagnosed with this premalignant disorder develop<unk>  at a rate of 10% per year for the first 5 years, 3% per year for the next 5 years, and then 1% per year. * Obesity is related to<unk>  with each increase of body mass index by five increasing the risk by 11%. Studies have reported a familial predisposition to<unk> . Hyperphosphorylation of a number of proteins—the paratarg proteins—a tendency that is inherited in an autosomal dominant manner, appears a common mechanism in these families. This tendency is more common in African-American with<unk>  and may contribute to the higher rates of<unk>  in this group. Epstein–Barr virus Rarely, Epstein–Barr virus (EBV) is associated with<unk> , particularly in individuals who have an immunodeficiency due to e.g. HIV/AIDS, organ transplantation, or a chronic inflammatory condition such as rheumatoid arthritis. EBV-positive<unk>  is classified by the World Health Organization (2016) as one form of the Epstein–Barr virus-associated lymphoproliferative diseases and termed Epstein–Barr virus-associated plasma cell<unk> . EBV-positive disease is more common in the plasmacytoma rather than<unk>  form of plasma cell cancer. Tissues involved in EBV+ disease typically show foci of EBV+ cells with the appearance of rapidly proliferating immature or poorly differentiated plasma cells. The cells express products of EBV genes such as EBER1 and EBER2. While the EBV contributes to the development and/or progression of most Epstein–Barr virus-associated lymphoproliferatve diseases, its role in<unk>  is not known. However, people who are EBV-positive with localized plasmacytoma(s) are more likely to progress to<unk>  compared to people with EBV-negative plasmacytoma(s). This suggest that EBV may have a role in the progression of plasmacytomas to systemic<unk> .
Multiple myeloma
Monoclonal gammopathy of renal significance  Monoclonal gammopathy of renal significance  1
Monoclonal gammopathy of undetermined significance
Monoclonal gammopathy of renal significance
Smouldering myeloma
Waldenström macroglobulinemia
AL amyloidosis
Plasma cell leukemia