Myeloma Nurse Learning Programme Module 1 – Overview and epidemiology of myeloma Aetiology (cause) of myeloma

Aetiology (cause) of myeloma

The underlying cause or aetiology of myeloma is not fully understood. The disease begins with a change in the genetic material within a small number of plasma cells. Some of these occur as abnormalities in the chromosomes while others are genetic mutations within the DNA sequence.

These changes alter the ability of affected plasma cells to divide and proliferate in a regulated way and increase their risk of becoming cancerous. For myeloma to develop, additional genetic and/or environmental factors are needed, although the exact nature of these is not known.

Several environmental factors have been linked to an increased risk of developing myeloma. These include exposure to:

Radiation – people who have been exposed to high levels of radiation e.g from an atomic bomb blast, or those who have been exposed to lower levels of radiation e.g. radiation workers
Occupation-related substances encountered in various industries e.g. agriculture (farming), textiles, painting, metal, wood, leather and petroleum sectors
Chemicals such as benzene and other solvents. A meta-analysis of cancer risk amongst firefighters reported an increased risk of myeloma and several studies showed that there was an increased incidence of myeloma in first responders to the 9/11 disaster
Viruses e.g. some studies have shown that people with chronic infections such as hepatitis C and HIV are at a greater risk of myeloma

Myeloma is 2-3 times more common in black people than in white people and is more likely to affect black people at a younger age than other ethnic groups. The reasons for this are not understood but there is likely to be a genetic component, with research identifying certain genetic abnormalities linked to the development of MGUS and/or myeloma that are more common among black people.

Studies have demonstrated an approximate two-fold increased risk amongst immediate family members. i.e. the incidence increases from 1 per 10,000 in the general population to 2 per 10,000 amongst families. While myeloma is not an inherited cancer in that it is not caused by one or two inherited genes, research still aims to identify genetic variations that might increase the likelihood of someone developing myeloma. G

This will be discussed in more detail in Module 2 – Pathogenesis of myeloma.

Aetiology (cause) of myeloma

Further reading