What other blood tests are useful if you suspect a myeloma diagnosis?

In terms of other blood tests that we like to do to help decide whether people have myeloma or not, somewhere around 70% of people will have anemia. Anemia basically means a low number of red blood cells. Of course, there are actually many types of anemia that a person can have. In general, for a person with myeloma, the size of the red cells will be normal, so we call that a normocytic anemia. That's typically what people have. Sometimes the red cells are a little bit larger. But anemia is a very common feature, and that's usually defined as a hemoglobin under ten grams per deciliter of blood. Often a person has a normal platelet count and white count. Sometimes those can be lower, but that is not as frequently seen a feature.

As I mentioned, we do look at kidney function, and that can be an important determinant of not only whether the person has myeloma or not, but it actually has some significance for prognosis later on and how we treat patients. So we're very interested in that number creatinine. We also look at albumin. That's a normal protein synthesized in the liver, and an albumin that is below normal is often a sign that a person has myeloma. It can also be connected with how a person may do with their myeloma.

Other abnormalities would be an elevation of what's called total protein. Very simplistically, total protein is a measure of albumin plus antibody levels. If that level is very high, that can signify a person has myeloma, or conversely, if it's very low, sometimes a person with light chain myeloma, about 20%, the normal antibody levels are very low. So we look at that.

In addition, there is calcium. About 20% of people newly diagnosed with myeloma will have a high calcium level when they first get diagnosed. We also look at something called LDH or lactate dehydrogenase. The amount of that varies from clinic to clinic, from lab to lab, but it is considered important if that level is above normal limits. So we look at that, as it can have prognostic value.

We also look at a tumor marker called beta two microglobulin. Beta two microglobulin is a protein that is part of the human leukocyte antigen complex or HLA one complex that is expressed on blood cells. A high level of beta two microglobulin typically means a person has more myeloma, and a lower level means that they have less.