A risk factor is anything that increases a person's chance of getting a disease such as cancer. Different cancers have different risk factors. For example, exposing skin to strong sunlight is a risk factor for skin cancer. Smoking is a risk factor for cancers of the lung, mouth, larynx, bladder, kidney, and several other organs. But having a risk factor, or even several, does not mean that a person will get the disease.

Scientists have found few risk factors that make a person more likely to develop multiple myeloma.

Age and Gender

Age is the most significant multiple myeloma risk factor. Only 1% of cases are diagnosed in people younger than 40. Two-thirds of people diagnosed with this cancer are over 65 years old. Men are 50% more likely to develop multiple myeloma than women.

Race

Multiple myeloma is over twice as common among black Americans as white Americans. The reason is not known.

Radiation Exposure

Exposure to radioactivity has been suggested as a risk factor but accounts for a very small number of cases.

Family History

This cancer seems to be more common in some families. If a person has a sibling or parent with myeloma their chance of developing it is nearly 4 times that of the general population. This is quite rare, however, and most patients have no affected relatives.

Occupational Exposure

Some studies have suggested that workers in certain petroleum-related industries may be at a higher risk.

Obesity

A recent study by the American Cancer Society has found that being overweight or obese increases a person’s risk of developing myeloma.

Other Plasma Cell Diseases

Many people with MGUS or solitary plasmacytoma will eventually develop multiple myeloma.

Revised: 08/04/2006