Pathophysiology refers to changes in bodily processes that result from disease. In the case of multiple myeloma (MM), which is a type of bone marrow cancer, the pathophysiology is complex. It can lead to bone, blood, kidney, and sometimes neurological problems.
MM pathophysiology has a widespread impact on the body. That is why an individual may require multiple blood tests, imaging tests, and biopsies for doctors to diagnose MM and determine a suitable treatment plan.
In this article, we discuss the pathophysiology of MM. We also look at the causes of the condition, as well as diagnosis and treatment options.
MM is a type of bone marrow cancer that accounts for
- aged over 65 years
MM causes bone symptoms, such as pain, fractures, and collapsed vertebrae, which may lead to a curved spine and spinal cord compression. Other serious health problems it can cause throughout the body include:
- weight loss
- kidney failure
- recurrent infections
The pathophysiology of MM affects skeletal, blood, kidney, and neurological processes.
Skeletal complications are common in MM. Around
MM can interfere with an important, lifelong process called bone remodeling. In this process, cells called osteoclasts dissolve older bone tissue, and cells called osteoblasts replace them with newer, stronger cells.
For bone remodeling to work, there must be a healthy balance between the osteoclast and osteoblast activity. Special bone cells called osteocytes are crucial here, as they regulate the activity of osteoclasts and osteoblasts.
People with MM have fewer useful osteocytes than average, which compromises bone remodeling, leading to bone problems, such as fractures and pain.
Hematology refers to the blood. When a person has cancer, their cells develop uncontrollably, resulting in many dysfunctional cells.
As MM cancer cells grow and proliferate within the bone marrow, it struggles to
- anemia, which occurs when a person has low levels of red blood cells
- neutropenia, which is when the levels of white blood cells called neutrophils are low
- thrombocytopenia, which is when there are low levels of platelets in the bloodstream
Plasma cells are white blood cells, and MM can affect their production and growth. These cells can overwhelm the kidneys in people with MM, causing blockages, inflammation, and cell damage.
MM affects the nervous system in around 1% of people with the condition. This rare but serious complication occurs when white blood cells enter the central nervous system, cerebrospinal fluid, or meninges, which are the membranes covering the brain and spinal cord.
Scientists remain unsure about how exactly this process occurs. However, there is evidence that genetic mutations in tumor suppressor cells could play a role.
Experts understand the general processes driving MM. The condition belongs to a spectrum of disorders affecting the growth of long-lived plasma cells.
Before developing active MM, individuals pass through two earlier asymptomatic disease stages called monoclonal gammopathy of undetermined significance (MGUS) and smoldering multiple myeloma (SMM).
MGUS is the earliest stage with no active symptoms, and it is not cancer. People with MGUS have low levels of a blood protein called monoclonal protein, or M protein. Only 20% of individuals with MGUS progress to MM.
SMM is the stage between MGUS and MM. People with SMM have a higher level of M protein and more abnormal plasma cells in the bone marrow than with MGUS.
Scientists do not know the exact cause of MM. However, like all cancers, MM develops when genetic mutations cause particular cells to grow uncontrollably. In the case of MM, these cells are long-lived plasma cells, which can stay in the bone marrow for long periods.
Health experts know that genetic mutations in specific proteins,
However, there is
Doctors need to perform various tests to diagnose MM,
- complete blood count
- calcium blood test
- creatinine blood test
- bone marrow examination
- a whole body scan to detect any skeletal problems
- serum-beta-2 microglobulin
- lactate dehydrogenase
Thanks to new treatments and improved supportive care, survival rates for people with MM have
Some standard MM treatment options include:
- stem cell transplantation
- corticosteroids, for their anti-inflammatory and immunosuppressive effects
- chemotherapy, to kill cancer cells
- proteasome and histone deacetylase inhibitors, to slow cancer progression
- monoclonal antibodies, to help during an MM relapse
Many cancer treatments carry a risk of significant side effects. For example, there is
- muscle weakness
- mood problems
Similarly, chemotherapy often kills healthy cells in addition to cancer cells, leading to side effects,
MM is a potentially serious type of bone marrow cancer. It can affect the bones, blood, kidneys, and brain.
Doctors may use numerous blood tests, imaging tests, and biopsies to diagnose the condition. Moreover, because MM is complex, an individual may require various treatments to improve their outlook.