

DIAGNOSIS AND TREATMENT OF MULTIPLE
MYELOMA AND OTHER PLASMA CELL DISORDERS
MULTIPLE MYELOMA:
Multiple myeloma is a prototype of a group of conditions known as
plasma cell neoplasm's. Plasma cell neoplasm's are a group of related disorders each of
which is associated with proliferation and accumulation of immunoglobulin-secreting cells
that are derived from the B-cell series of immunocytes. Monoclonal components occur in
both the malignant plasma cell disorders, that is say, multiple myeloma, Waldenstrom's
macroglobulinemia, solitary bone plasmacytoma, extra medullary plasmacytoma,
osteosclerotic myeloma (POEMS Syndrome), amyloidosis, and heavy chain disease, as well as
in the clinically unclear monoclonal gammopathy of undetermined significance/smoldering
multiple myeloma.
PRESENTING SIGNS AND SYMPTOMS:
The clinical features of multiple myeloma develop from tissue damage
by multiple bone tumors, complications from the monoclonal component, and an increased
vulnerability to infections due to depressed normal immunoglobulin levels. These
complications provide the first clues to the diagnosis and form the basis for defining the
stage and prognosis.
Subjective:
- Skeletal System
- Bone pain is the most common symptom resulting from pathologic
fractures.
- Compression fractures of the thoracic and lumbar vertebral bodies
usually result in severe spasms and back pains. Multiple compression fractures may
culminate in painless dorsal kyphosis and loss of as much as six inches of height.
- Pleuritic pain from pathologic rib and clavicular fractures is also
common and is associated with marked local tenderness.
- Destruction of the proximal bones of the extremities is less frequent
and distal bones of the extremities are rarely affected.
- Band-like or radicular pain should alert the clinician to impending
spinal cord impression and is a serious complication representing an emergency requiring
immediate diagnosis and treatment.
- Hypercalcemia
- Nausea, confusion, polyuria and constipation are common symptoms
secondary to hypercalcemia.
- Anemia
- Easy fatigability or dyspnea on exertion is usually secondary to
anemia.
- Hyperviscosity
- When immunoglobulins are present at concentrations greater than 5
gm/dl, some IgG or IgA multiple myeloma globulin's can produce features of hyperviscosity
syndrome. Lassitude, confusion, headache, transient disturbances of vision and increased
bleeding tendency could be related to this syndrome.
- Infections
- Recurrent bacterial infections are a major cause of illness and are
the most common cause of death in-patients with advanced myeloma.
- Amyloid
- Systemic amyloidosis with or without multiple myeloma could present
with weakness, weight loss, ankle edema, dyspnea, paraesthesias, lightheadedness or
syncope.
- Aching in the hands, particularly at night, can signify median nerve
compression associated with Carpal Tunnel Syndrome, caused by amyloid infiltration of the
transverse carpal ligament.
Objective:
No specific physical abnormalities may be detected.
- Skeletal System
- Most patients with symptomatic myeloma will have tenderness on
pressure over an involved bone, kyphosis or a pathologic fracture to indicate the sight of
bone lesions.
- In approximately 15% of patients, firm plasma cell tumors arise from
areas of underlying bone destruction and may be palpated on the skull, sternum, clavicles
and ribs, where the affected bone is close to the skin.
- Spinal examination could reveal kyphosis and on palpation, tenderness
at the area of fracture or plasmacytoma, also palpation could trigger radiculopathy that
could help in localizing the site of imminent cord compression. Upper extremities could
demonstrate signs of carpal tunnel syndrome.
- Hyperviscosity
- Fundal examination, especially in patients with suspected
hyperviscosity syndrome, could reveal segmental dilatation of the retinal veins with
retinal hemorrhages.
- Plasmacytoms
- Mouth, throat and neck examination might reveal extra medullary
plasmacytoma, which usual develop in the nasopharyngeal area or paranasal sinuses.
- Neurologic signs could be caused by spinal cord or nerve root
compression, sensory motor peripheral neuropathy or myelomatosis meningitis.
- In the rare instances where pleural effusion may develop from
plasmacytoma and plasmacytosis, pleural effusion could be detected clinically and
radiologically
- Spinal examination could reveal kyphosis and on palpation, tenderness
at the area of fracture or plasmacytoma, also palpation could trigger radiculopathy, which
could help in localizing the site of imminent cord compression. Upper extremities could
demonstrate signs of carpal tunnel syndrome.
- Infections
- Signs of lobular pneumonia could be detected on auscultation and
palpation of the chest.
- Amyloid
- Cardiac examination could reveal ventricular gallop as a sign of
failure secondary to severe anemia, hypercalcemia or amyloid heart disease.
- Skin plaques secondary to amyloid deposit, also joint infusions may
be presenting features. Generalized edema secondary to nephrotic syndrome and/or
congestive heart failure could be elicited from the physical examination.
COURSE OF THE DISEASE:
The median survival of multiple myeloma without any treatment is
seven months. Since the introduction of chemotherapy, the median survival has improved to
36-48 months. Cure is rare in this disease. Several clinical and laboratory parameters
provide important prognostic information that is extremely valuable in evaluating disease
progression and different treatment regimens.
Prognostic factors
- The staging system of Durie and Salmon which is based on hemoglobin,
serum calcium, and monoclonal protein concentration, as well as the characteristics of the
bone survey, classify patients into three stages which correlate with myeloma cell mass.
- Serum beta-2 microglobulin uncorrected for serum creatinine predicts
survival remarkably well in myeloma patients.
- Karyotypic abnormalities occur in 30% of myeloma patients.
Irrespective of the treatment status, patients with an abnormal karyotype have a
significantly shorter median survival than those with a normal karyotype.
- The plasma cell labeling index powerfully and independently predicts
survival. Also, it is a useful tool to differentiate between monoclonal gammopathy of
undetermined significance and multiple myeloma.
- Other prognostic factors such as serum Interleukin-6, C-reactive
protein, serum Interleukin-2, and serum IL-6 receptor appear to be other factors that
could assist in predicting the course of the disease and/or response to therapy.
COMPLICATIONS:
- Bone destruction
-
Approximately 20% of patients with multiple myeloma have bone demineralization only.
Radiographs of the axial skeleton, which must include both femurs, will support the
diagnosis of multiple myeloma in approximately 70% of patients. 10% of patients will have
a normal skeletal survey, presumably because at least 30% of bone calcium must be lost
before radiographic changes are evident. Rarely, in 1.4% of patients an osteoblastic
reaction is present, which is suggestive of the POEMS syndrome (polyneuropathy,
organomegaly, endocrinopathy, monoclonal protein and skin changes). Bone destruction -
Approximately 20% of patients with multiple myeloma have bone demineralization only.
Radiographs of the axial skeleton, which must include both femurs, will support the
diagnosis of multiple myeloma in approximately 70% of patients. 10% of patients will have
a normal skeletal survey, presumably because at least 30% of bone calcium must be lost
before radiographic changes are evident. Rarely, in 1.4% of patients an osteoblastic
reaction is present, which is suggestive of the POEMS syndrome (polyneuropathy,
organomegaly, endocrinopathy, monoclonal protein and skin changes).
- Renal Failure
-
Renal failure occurs in approximately 25% of patients, more frequently in-patients with
more extensive disease. Most patients with mild azotemia have no symptoms, however easy
fatigability, nausea, vomiting, and confusion occur with severe renal insufficiency.
Pathogenesis is multi-factorial, but more than 90% of patients with renal failure have
Bence-Jones proteinuria or hypercalcemia or both. -
Renal failure occurs in approximately 25% of patients, more frequently in-patients with
more extensive disease. Most patients with mild azotemia have no symptoms, however easy
fatigability, nausea, vomiting, and confusion occur with severe renal insufficiency.
Pathogenesis is multi-factorial, but more than 90% of patients with renal failure have
Bence-Jones proteinuria or hypercalcemia or both.
- Infection
-
Recurrent bacterial infections are a major cause of illness and are the most frequent
cause of death in-patients with advanced myeloma. Infections result primarily from the
marked depression of production of normal immunoglobulins that occur in more than 75% of
patients. Streptococcus pneumonia Hemophilus influenzae, are the most common pathogens in
previously untreated myeloma patients and in non-neutropenic patients who respond to
chemotherapy. However, in neutropenic patients and in those with refractory disease,
staphylococcus aureus and gram-negative bacteria are the predominant organisms.
Pneumococcal vaccination may be worth trying, however most multiple myeloma patients
respond poorly to bacterial antigenic stimulation. Herpes zoster could be seen in-patients
with multiple myeloma more commonly in those complicated by renal failure. Infection -
Recurrent bacterial infections are a major cause of illness and are the most frequent
cause of death in-patients with advanced myeloma. Infections result primarily from the
marked depression of production of normal immunoglobulins that occur in more than 75% of
patients. Streptococcus pneumonia Hemophilus influenzae, are the most common pathogens in
previously untreated myeloma patients and in non-neutropenic patients who respond to
chemotherapy. However, in neutropenic patients and in those with refractory disease,
staphylococcus aureus and gram-negative bacteria are the predominant organisms.
Pneumococcal vaccination may be worth trying, however most multiple myeloma patients
respond poorly to bacterial antigenic stimulation. Herpes zoster could be seen in-patients
with multiple myeloma more commonly in those complicated by renal failure. -
Recurrent bacterial infections are a major cause of illness and are the most frequent
cause of death in-patients with advanced myeloma. Infections result primarily from the
marked depression of production of normal immunoglobulins that occur in more than 75% of
patients. Streptococcus pneumonia Hemophilus influenzae, are the most common pathogens in
previously untreated myeloma patients and in non-neutropenic patients who respond to
chemotherapy. However, in neutropenic patients and in those with refractory disease,
staphylococcus aureus and gram-negative bacteria are the predominant organisms.
Pneumococcal vaccination may be worth trying, however most multiple myeloma patients
respond poorly to bacterial antigenic stimulation. Herpes zoster could be seen in-patients
with multiple myeloma more commonly in those complicated by renal failure.
- Hyperviscosity syndrome
-
Symptoms and signs of this condition are generally not seen unless the relative serum
viscosity is greater than 4.0 units (normal range 1.4-1.8) and the full blown classic
syndrome is usually not observed unless the viscosity is greater than 5.0 units. The signs
and symptoms include lassitude, confusion, blurred vision, dizziness, vertigo, diplopia
and increase tendency to bleeding, especially oronasal bleeding. -
Symptoms and signs of this condition are generally not seen unless the relative serum
viscosity is greater than 4.0 units (normal range 1.4-1.8) and the full blown classic
syndrome is usually not observed unless the viscosity is greater than 5.0 units. The signs
and symptoms include lassitude, confusion, blurred vision, dizziness, vertigo, diplopia
and increase tendency to bleeding, especially oronasal bleeding.
- Neurologic
-
Thoracic or lumbosacral radiculopathy is the most frequent neurologic complication. Root
pain results from compression of the nerve by the vertebral lesion or by the collapsed
bone itself. Spinal cord or cord compression from an extradural plasma cell tumor results
in back pain with radicular features, weakness or paralysis where an immediate diagnosis
and treatment is necessary. Occasionally, patients with multiple myeloma experience
peripheral neuropathy, which may be severe. Electromyography studies suggest that this
complication occur more frequently than clinically recognized. Although the pathogenesis
is unclear, the neuropathy may be caused by associated amyloidosis in some patients.
Severe motor neuropathy occurs more frequently in younger patients with localized or
osteosclerotic myeloma. -
Thoracic or lumbosacral radiculopathy is the most frequent neurologic complication. Root
pain results from compression of the nerve by the vertebral lesion or by the collapsed
bone itself. Spinal cord or cord compression from an extradural plasma cell tumor results
in back pain with radicular features, weakness or paralysis where an immediate diagnosis
and treatment is necessary. Occasionally, patients with multiple myeloma experience
peripheral neuropathy, which may be severe. Electromyography studies suggest that this
complication occur more frequently than clinically recognized. Although the pathogenesis
is unclear, the neuropathy may be caused by associated amyloidosis in some patients.
Severe motor neuropathy occurs more frequently in younger patients with localized or
osteosclerotic myeloma.
- Hypercalcemia
-
At diagnosis, one-fourth of patients have serum calcium concentrations greater than 11.5
mg/dl after correction for serum albumin. Some hypercalcemic patients may not shown bone
destruction on radiographs. Nausea, confusion, polyuria and constipation are common
symptoms. Hypercalcemia -
At diagnosis, one-fourth of patients have serum calcium concentrations greater than 11.5
mg/dl after correction for serum albumin. Some hypercalcemic patients may not shown bone
destruction on radiographs. Nausea, confusion, polyuria and constipation are common
symptoms.
- Secondary malignancies
-
Secondary acute leukemia develops in approximately 2% of patients who survive 2 years,
which is 50-100 times more frequent than in normal individuals. Fewer than 5% of patients
with multiple myeloma have acute leukemia diagnosis or acquire the disease within several
months after starting chemotherapy. The frequency of solid tumors in multiple myeloma
patients is no higher than in persons of similar age or sex. Secondary malignancies -
Secondary acute leukemia develops in approximately 2% of patients who survive 2 years,
which is 50-100 times more frequent than in normal individuals. Fewer than 5% of patients
with multiple myeloma have acute leukemia diagnosis or acquire the disease within several
months after starting chemotherapy. The frequency of solid tumors in multiple myeloma
patients is no higher than in persons of similar age or sex.
Secondary acute leukemia develops in approximately 2% of patients who survive 2 years,
which is 50-100 times more frequent than in normal individuals. Fewer than 5% of patients
with multiple myeloma have acute leukemia diagnosis or acquire the disease within several
months after starting chemotherapy. The frequency of solid tumors in multiple myeloma
patients is no higher than in persons of similar age or sex.
LABORATORY PROCEDURES:
Changes Noted on Routine Screening Tests:
Routine laboratory screening, such as CBC, SMA-16, urinalysis and
chest x-ray are usually nonspecific regarding reaching a diagnosis, however are extremely
helpful in pointing to specific diagnostic procedures.
- CBC
- Anemia is present in most patients and provides a major diagnostic
clue. Several factors account for anemia, such as bone marrow infiltration by plasma
cells, renal failure and chronic disease. Low serum B-12 levels may occur without signs of
functional B12 deficiency; however, evaluation of B12 deficiency should be sought. High
levels of IgA or IgG frequently increase the plasma volume and the hematocrit may be 6
points less than the value expected from the measured red cell volume.
- Thrombocytopenia is uncommon at the time of diagnosis and usually
reflects a marked degree of bone marrow replacement by plasma cells.
- Mild granulocytopenia occurs frequently for reasons that are unclear
and usually persist throughout the clinical course. Granulocytopena does not have any
impact on the outcome of the disease.
- Immunoglobulins
- Elevated total globulins, hypoalbuminemia or overall hypoproteinemia
secondary to nephrotic syndrome could be observed.
- Chemistry
- Hypercalcemia, hyperuricemia, increased serum creatinine secondary to
multiple myeloma and/or renal failure.
- Increased LDH is noted in 10-15% of patients and usually signifies a
poor prognosis.
- The serum alkaline phosphatase is usually normal but may be elevated
in-patients with healing pathologic fractures or osteosclerotic lesions.
- Proteinuria is detected in approximately 65% of patients.
- Radiological Studies
- Chest x-ray may reveal osteolytic lesions in the clavicles, scapulae
or ribs, a subpleural plasmacytoma attached to a rib or a pleural effusion.
- Cardiomegaly may be seen in-patients with cardiac amyloidosis.
Diagnostic procedures and Tests:
When plasma cell dyscrasia is suspected the following tests should
be performed to confirm the diagnosis, detect complications, assist in the staging of the
disease and establish baseline values for following the treatment progress.
- Myeloma Proteins:
Serum and urine protein electrophoresis demonstrate a peak or
localized band in 80% of patients, hypo-gammaglobulinemia in 10% and no apparent
abnormalities in the remainder. In multiple myeloma patients with hypogammaglobulinemia
almost always these patients have a monoclonal light chain protein in the urine.
Immunoelectrophoresis and immune fixation are rather expensive, however are very sensitive
when compared to protein electrophoresis which could miss up to 15% of monoclonal
gammopathies. In 99% of the cases, a monoclonal protein in the serum or the urine or both
is detected and in 1% of the patients no monoclonal protein is noted indicating
nonsecretory multiple myeloma which is secondary to a defect in the synthesis or assembly
of the light or heavy chains.
- Bone Marrow Aspirate and Biopsy:
This procedure is helpful in evaluating the different etiologies for
the cytopenias and is also crucial for the diagnosis of multiple myeloma as well as
evaluating cell morphology and biology for prognosis. Bone marrow plasmacytosis may be
spotty but an increase in the bone marrow plasma cells is usually easy to demonstrate from
most bone marrow sites. Reactive plasmacytosis secondary to connective tissue disorders,
liver disease, viral and bacterial infections, and carcinoma could be differentiated from
the monoclonal plasma cell proliferation of multiple myeloma or monoclonal gammopathy of
unknown significance by performing immune staining on the bone marrow.
If available, plasma cell labeling index on the bone marrow could
add important prognostic information and possibly aid in structuring the management plans
for the patient. A labeling index of less or equal to 0.8% usually indicates a good
prognosis. Cytogenetic abnormalities occur in 30% of multiple myeloma patients and its
presence usually indicates shorter median survival. Numeric anomalies occurred most often
in chromosome 11 and structural aberrations occurred most often in chromosomes 1, 11 and
14.
- Urinalysis:
Proteinuria is detected in approximately 65% of patients. The
recognition of light chain protein (Bence-Jones protein) depends on the demonstration of
the monoclonal light chain by immune electrophoresis or immune fixation. 24 hour urine
collection for protein quantitation supplemented by urine protein electrophoresis is
essential for following response to therapy.
- Radiologic Procedures:
A complete bone survey is an essential part of the evaluation of
monoclonal gammopathies. The skeletal survey should include the complete spine, long bones
of the arms and legs, skull, ribs, and pelvis. The order listed is the order of frequency
of involvement. Approximately 20% of patients will have bone demineralization alone.
Radiographs of the axial skeleton, which must include bone femurs, will support the
diagnosis of multiple myeloma in approximately 70% of the patients. Punched out lesions
are best seen on lateral skull radiographs. 10% of the patients will have a normal
skeletal survey at the time of diagnosis.
- Computed Tomography and Magnetic Resonance Imaging;
May detect bone destruction more sensitively and especially useful
in detecting the extent of extra medullary soft tissue lesions. MRI of the lumbar spine
and pelvis may detect more advanced disease that may require chemotherapy, primarily
in-patients with an apparently localized plasmacytoma or with asymptomatic indolent
multiple myeloma.
DIFFERENTIAL DIAGNOSIS:
Lytic bone lesions could be related to metastatic carcinoma,
connective tissue diseases, chronic infections or lymphoma.
Patients with multiple myeloma must be differentiated from those
with monoclonal gammopathy of undetermined significance and smoldering multiple myeloma.
Asymptomatic patients with an M-component of less than 3 gm/dl, fewer than 10% bone marrow
plasma cells and absence osteolytic lesions, anemia, hypercalcemia, or renal function
impairment have monoclonal gammopathy of unknown significance. Asymptomatic patients who
have both an M-component higher than 3 gm/dl or more than 10% but less than 20% bone
marrow plasma cells fulfill the criteria for smoldering multiple myeloma. These patients
do not have anemia, renal failure, hypercalcemia, osteolytic bone lesions or other
clinical manifestations related to the monoclonal protein. Clinically and biologically
these patients with smoldering multiple myeloma are closer to monoclonal gammopathy of
undetermined significance than to overt multiple myeloma. The recognition of these
patients is extremely important because they should not be treated with chemotherapy until
progression occurs. There is no particular lab parameter or clinical factor that could
differentiate patients with MGUS/SMM from overt multiple myeloma. The decrease levels of
uninvolved immunoglobulins are not a useful criterion for differentiation because 30-40%
of patients with MGUS also have a decrease in the uninvolved immunoglobulin. Although the
presence of Bence-Jones proteinuria is suggestive of multiple myeloma, it is not unusual
to find small amounts of monoclonal light chains in the urine of patients with MGUS. Lytic
bone lesions in the skeletal survey strongly suggest the diagnosis of multiple myeloma.
In-patients recently diagnosed with MGUS, serum electrophoresis should be repeated after
three months to exclude an early myeloma and if results are stable the test should be
repeated in six months. Patients should be aware that the evolution of MGUS to multiple
myeloma can be abrupt and therefore they should be re-examined promptly if their clinical
condition deteriorates.
THERAPY FOR MULTIPLE MYELOMA
MM remains a disease for which cure is a rarity. Most pts succumb to
their disease within 36-48 months from the time of diagnosis. Limitations of effective
therapy for MM are primarily associated with the low cell proliferation rate and
multi-drug resistance. Therapy for multiple myeloma includes induction, maintenance, and
supportive aspects. The induction portion of the treatment aims at reducing the tumor
volume, and achieving a plateau phase. The standard maintenance approach is no treatment.
Different drugs, and treatment modalities as bone marrow transplantation has been
entertained, and used with out a significant impact on the disease free or the overall
survival. Supportive care in multiple myeloma has advanced significantly over the past few
years. Growth factor support with erythropoeitin replacement, GM-CSF for stimulating the
WBC is a safe and effective method to decrease or prevent the occurrence or the severity
of neutropenia. Cell component support, has improved with a better chances at a
transfusion match with lower complication rates.
The different regimens used in the induction portion of the disease
are overall comparable. The difference between the regimens is mainly related to the
toxicity profile, as well as the quickness of response, and the ability of the combination
to reverse some of the combination side effects.
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