Amyloidosis Treatments
How Is Amyloidosis Treated?
Because there are several types of amyloidosis with highly varied treatment and management approaches, patients require a careful clinical evaluation that includes a thorough medical history and exam, laboratory studies of blood and urine, and possible biopsies of the bone marrow, abdominal fat and other organs.
A multidisciplinary team is needed to manage patients because amyloid protein can deposit in various organs and tissues.
- Light chain amyloidosis occurs due to an abnormal population of blood cells in the bone marrow. A hematologist is needed to manage the chemotherapy and treatment regimens that are often effective but may have toxicity.
- Amyloid fibrils frequently deposit in the heart, causing thickening of the heart walls and congestive heart failure symptoms. Medications traditionally used to treat heart failure are often poorly tolerated by amyloid patients, so specific expertise is needed. Patients with cardiac amyloidosis often need specific testing available at City of Hope, such as electrocardiogram, echocardiogram, cardiac magnetic resonance imaging and nuclear medicine imaging techniques.
- Amyloids often deposit in the kidneys, causing protein loss in the urine. This, too, can have specific implications, so the expertise of nephrology is often needed.
- While systemic amyloidosis does not involve the brain or spinal cord, amyloid fibrils often deposit in the peripheral nervous system, causing peripheral motor/sensory and autonomic neuropathy. Therefore, a neurologist is often a vital member of the team.
Because light chain amyloidosis is similar to myeloma, a cancer of plasma cells, many of the same treatments used for myeloma are also used to treat amyloidosis, such as:
- Drug therapy, including chemotherapy or steroid treatments
- Stem cell transplantation
- Immunotherapy
- Radiation therapy
Transthyretin (TTR) amyloidosis is a unique form of systemic amyloidosis and can most commonly involve the heart, kidneys and peripheral nervous system. TTR amyloidosis develops as a result of the transthyretin protein becoming unstable and then misfolding into amyloid fibrils. The instability of TTR can be due to either older age in the setting of a normal TTR protein, as is the case for wild type or senile amyloidosis, or as a result of an inherited mutation of the TTR protein, as is the case for hereditary amyloidosis. Fortunately, there are now treatments for TTR amyloidosis that include protein stabilizers, as well as molecules that inhibit the production of amyloidogenic proteins. At City of Hope, we have access to the latest approved treatments for TTR amyloidosis, as well as investigative studies.
Secondary amyloidosis is a third type of systemic amyloid disease that is due to a chronic inflammatory process causing a protein normally found in the body, amyloid precursor protein (APP), to misfold and form amyloid fibrils. These fibrils can then deposit in tissues and organs causing damage. A deliberate and thoughtful process is needed to definitively establish an accurate diagnosis of secondary amyloidosis, which is then treated by controlling the cause of inflammation.
It is critical to accurately define the type of amyloidosis so appropriate treatments can be provided and other treatments that may have toxicities can be avoided.