Pathology
v Type -
Cancer
v
v Cause(s) - Unknown
v Symptoms - Bone pain, widespread infection, kidney failure, anaemia,
neurological symptoms.
v Mortality Rate - Inevitably fatal if untreated. Even if
treated, 50% mortality rate after five years.
v Treatments - Chemotherapy, thalidomide, steroids, stem cell transplant
v
What is multiple myeloma?
Multiple
myeloma, also known as plasma cell myeloma, is a cancer of plasma cells, a type
of white blood cell normally responsible for producing antibodies. Often, no
symptoms are noticed initially. When advanced, bone pain, bleeding, frequent infections,
and anemia may occur. Complications may include amyloidosis.
You
may not require treatment until symptoms develop, and most people respond well
to treatments that include:
• Chemotherapy
• Radiation
• Blood treatment called plasmapheresis.
In
some cases, a bone marrow or stem cell transplant is an option.
Multiple
myeloma is not considered “curable,” but symptoms wax and wane. There can be a
long period of dormancy that could last several years. However, this cancer
usually recurs.
There
are several types of myeloma, but multiple myeloma accounts for 90 percent of
cases, according to the Leukemia and Lymphoma Society. The Surveillance,
Epidemiology, and End Results Program (SEER) list myeloma as the 14th most
common type of cancer.
The
cause is generally unknown. Risk factors include drinking alcohol and obesity.
The underlying mechanism involves abnormal plasma cells producing abnormal
antibodies which can cause kidney problems and overly thick blood. The plasma
cells can also form a mass in the bone marrow or soft tissue. When only one
mass is present, it is known as a plasmacytomawhile more than one is known as
multiple myeloma. Multiple myeloma is diagnosed based on blood or urine tests
finding abnormal antibodies, bone marrow biopsy finding cancerous plasma cells,
and medical imaging finding bone lesions. Another common finding is high blood
calcium levels.
Multiple
myeloma is considered treatable, but generally incurable. Remissions may be
brought about with steroids, chemotherapy, thalidomide or lenalidomide, and
stem cell transplant. Bisphosphonates and radiation therapy are sometimes used
to reduce pain from bone lesions.
Globally,
multiple myeloma affected 488,000 people and resulted in 101,100 deaths in
2015. In the United States, it develops in 6.5 per 100,000 people per year and
0.7% of people are affected at some point in their lives. It usually occurs
around the age of 61 and is more common in men than women. Without treatment,
typical survival is seven months. With current treatments, survival is usually
4–5 years. This gives a five-year survival rate around 49%.The word myeloma is
from the Greek myelo- meaning
"marrow" and -oma meaning "tumour
Signs and symptoms.-
Because many organs can be affected by
myeloma, the symptoms and signs vary greatly. A mnemonic sometimes used to
remember some of the common symptoms of multiple myeloma are CRAB:
C
= calcium (elevated),
R
= renal failure,
A
= anaemia
B
= bone lesions.
Myeloma
has many other possible symptoms, including opportunistic infections (e.g.,
pneumonia) and weight loss. CRAB symptoms and proliferation of monoclonal
plasma cells in the bone marrow are part of the diagnostic criteria of multiple
myeloma.
Treatment
Treatment
for multiple myeloma is focused on therapies that decrease the clonal plasma
cell population and consequently decrease the signs and symptoms of disease. If
the disease is completely asymptomatic (i.e. there is a paraprotein and an
abnormal bone marrow population but no end-organ damage), as in asymptomatic
("smoldering") myeloma, treatment is typically deferred, or restricted
to clinical trials.
In
addition to direct treatment of the plasma cell proliferation, bisphosphonates
(e.g., pamidronate or zoledronic acid) are routinely administered to prevent
fractures; they have also been observed to have a direct anti-tumor effect even
in patients without known skeletal disease. If needed, red blood cell
transfusions or erythropoietin can be used for management of Anaemia.
Prognosis-
Durie-Salmon
staging system
First
published in 1975, the Durie-Salmon staging system is still in use. However,
one of the limitations of the Durie-Salmon staging system is the subjectivity
in determining the extent of bone disease.
• Stage
I: all of
• Hb > 10g/dL
• normal calcium
• Skeletal survey: normal or single
plasmacytoma or osteoporosis
• Serum paraprotein level < 5 g/dL if
IgG, < 3 g/dL if IgA
• Urinary light chain excretion < 4
g/24h
• Stage II: fulfilling the criteria of
neither I nor III
• Stage III: one or more of
• Hb < 8.5g/dL
• high calcium > 12 mg/dL
• Skeletal survey: Three or more lytic
bone lesions
• Serum paraprotein > 7g/dL if IgG,
> 5 g/dL if IgA
• Urinary light chain excretion >
12g/24h
Stages
I, II, and III of the Durie-Salmon staging system can be divided into A or B
depending on serum creatinine:
• A: serum creatinine < 2 mg/dL (<
177 μmol/L)
• B: serum creatinine > 2 mg/dL (>
177 μmol/L)
Prevention
The
risk of multiple myeloma can be reduced by maintaining a normal body weight
Diagnosis
Myeloma
There
are two main systems used to stage multiple myeloma:
• International Staging System (ISS)
• Durie-Salmon system
Stage 1
In
this stage you have a relatively small number of myeloma cells in your blood
and urine. Your hemoglobin levels are only slightly below normal, and bone X-rays
may look normal or show only one affected area.
Stage 2
In
this stage a moderate number of myeloma cells are present. Hemoglobin levels
are usually much lower than normal. Monoclonal immunoglobulin may be increased,
and blood calcium levels may also be high. X-rays may show several areas of
bone damage.
Stage 3
In
the final stage of multiple myeloma, a high number of myeloma cells are found.
Your hemoglobin level is also usually below 8.5 grams per deciliter, and
calcium blood levels are high. And there are multiple areas of bone destruction
caused by the cancer.
Survival rates
Survival
rates are based on comparing people with myeloma to their peers who don’t have
cancer. According to the American Cancer Society (ACS), these are the average
survival rates by stage:
Stage
1: 62 months
Stage
2: 44 months
Stage
3: 29 months
It’s
important to note that survival rates are calculated from the time treatment
begins, and the average is the median survival rate. This means that half of
the people with multiple myeloma lived longer than the average length for each
stage.