Myeloma, or multiple myeloma, is a blood cancer that forms in a type of white blood cells called plasma cells. Plasma cells create immunoglobulins, or antibodies, that protect you against foreign invaders such as viruses and bacteria.
Myelomas are subcategorized depending on the type of immunoglobulins produced by the cancerous plasma cells. Light chain myeloma is the
In people with light chain myeloma, the cancerous plasma cells produce a type of immunoglobulin characterized as light chains.
Keep reading to learn about light chains and how light chain myeloma differs from other myelomas.
Plasma cells produce immunoglobulins to fight against foreign invaders. Immunoglobulins are made up of two subunits called light chains and two called heavy chains.
Normal immunoglobulins are classified as polyclonal proteins, whereas cancerous plasma cells produce monoclonal proteins only made up of one light chain and one heavy chain. These abnormal proteins can’t defend your body like normal immunoglobulins can.
Light chains are classified as kappa or lambda, depending on their molecular structure. Heavy chains are classified as G, A, D, E, or M.
Immunoglobin can be divided into 10 types depending on the type of heavy and light chains they’re made up of:
- IgG kappa
- IgG lambda
- IgA kappa
- IgA lambda
- IgD kappa
- IgD lambda
- IgE kappa
- IgE lambda
- IgM kappa
- IgM lambda
Multiple myeloma can be classified based on the types of immunoglobulins produced by cancerous plasma cells. The most common type is IgG kappa.
In people with light chain myeloma, also called Bence-Jones myeloma, cancer cells don’t produce entire immunoglobins. They only produce light chain proteins and no heavy chains.
Light chain myeloma can be classified as lambda or kappa light chain myeloma, depending on which type the cancerous cells produce. These light chains can build up in the kidneys, nerves, or other organs and cause serious complications.
These two types of proteins have different structures. The genes that code for kappa light chains are found on chromosome 2 while lambda genes are found on chromosome 22.
Research suggests that lambda light chain myeloma has a poorer prognosis than kappa light chain myeloma.
Specific symptoms of multiple myeloma can vary between people. Some people don’t have any symptoms whereas others develop serious complications.
The most common symptom associated with multiple myeloma is bone pain, which usually develops in the lower back or ribs.
People with light chain myeloma frequently develop symptoms affecting the kidneys due to the buildup of light chain proteins. A
In the later stages, light chain myeloma can develop into extramedullary disease, which is when the cancerous cells form tumors outside of the bone marrow.
People with light chain myeloma often develop medical problems that fall under the acronym CRAB, which stands for:
- calcium elevation
- renal dysfunction (kidney disease)
- anemia (low blood count)
- bone damage
Light chain myeloma shares a number of general symptoms with other forms of myeloma:
According to the
- increasing age, with most people diagnosed over 65
- male gender
- family history, although many people have no affected relatives
- being overweight or obese
- having another plasma cell disease such as monoclonal gammopathy
Multiple myeloma is also
Exposure to some toxic chemicals such as benzene and Agent Orange have been identified as myeloma triggers.
Diagnosis of light chain multiple myeloma starts with a general diagnosis of myeloma. Multiple myeloma is often detected with a blood or urine test before symptoms develop.
If your doctor detects signs of myeloma, you’ll need to undergo further tests. Blood and urine tests are used to look for markers of myeloma such as:
- elevated M protein
- abnormal plasma cells
- signs of kidney disease
- low blood cell counts
- high calcium levels
People with light chain myeloma don’t have the same spike of M protein characteristic of many other types of myeloma, which makes the disease more difficult to detect.
A blood or urine test will show an increased level of free light chains, and more importantly, an abnormal ratio of kappa to lambda light chains.
Once myeloma is detected on blood or urine tests, a doctor will order a bone marrow biopsy to look for cancerous plasma cells and confirm the diagnosis of multiple myeloma.
The best treatment for light chain myeloma depends on your symptoms and overall health. Your cancer team can help you determine the best options for your situation.
Multiple myeloma doesn’t have a cure, but it can often be successfully managed for many years. Types of treatment include:
- targeted therapy
- autologous stem cell transplant
- bone-modifying drugs
- radiation therapy
- supportive therapies such as blood transfusions and antibiotics
People with a build-up of light chains in their tissues are often given some combination of the drugs
According to the
The outlook for light chain myeloma is poorer than other myelomas such as
Light chain myeloma tends to more frequently cause kidney failure, bone disease, and a buildup of light chain cells in organs (light chain amyloidosis) when compared with classic multiple myeloma.
If more than 2 organs are affected, the estimated survival time of light chain myeloma is
Light chain myeloma is a rare type of blood cancer and a subtype of multiple myeloma. It’s characterized by the presence of light chain immunoglobulins in the blood and urine without a heavy chain component.
Light chain myeloma tends to have a poor outlook compared to other myelomas since it’s frequently more aggressive and often presents with kidney failure.
Take the time to discuss your outlook and treatment options with your doctor and cancer team so that you can create a management plan that works best for your individual cancer.