8 - Multiple Myeloma Flashcards
Multiple Myeloma
Neoplastic profileration of a single clone of plasma cells producing a monoclonal immunoglobulin
Multiple Myeloma - Incidence
Second most common hematologic malignancy
African americans 2 - 3 times higher risk than Caucasians, risk is lower in Asians
Slightly more frequent in men than women
Disease of older adults (median age at diagnosis is 66)
10% of patients younger than 50
2% younger than 40
IgM
Makes your blood hella viscous because it needs more space
Multiple Myeloma - Timeline
MGUS (smoldering myeloma) Active Myeloma First-line therapy Plateau remission Relapse Second-line therapy Plateau remission Relapse Third-line therapy Refractory relapse
Each plateau keeps getting higher and higher in terms of M-protein level
Disease not curable.
MGUS
Monoclonal Gammopathy of Undetermined Significance
No other signs of Multiple Myeloma
Often discovered accidentally via other blood work
At this point, it’s a pre-stage, so they don’t have cancer yet, but they need lifelong follow-ups to prevent progression to cancer.
Multiple Myeloma - Clinical Presentation
Anemia - 73% Bone Pain - 58% Elevated Creatinine - 48% Fatigue/Generalized Weakness - 32% Hypercalcemia - 28% Weight Loss - 24%, 1/2 of whom lost ≥ 9 kg
Multiple Myeloma - Diagnosis
Bone Marrow histology (see cancer cells)
Monoclonal immunoglobulins in serum & urine
X-ray, CT (lytic lesions)
Multiple Myeloma - Blood Work
CBC w/ differential & platelet counts
BUN, Creatinine
Electrolytes, calcium, albumin, LDH
Serum quantitative immunoglobulins
Serum protein electrophoresis and immunofixation
β2-M
Serum free light chain assay
Multiple Myeloma - Urine Evaluation
24-hr protein
Protein electrophoresis (quantitative Bence Jones protein)
Immunofixation electrophoresis
Multiple Myeloma - Other Evaluation
Skeletal Survey
Unilateral bone marrow aspirate and biopsy evaluation with immunohistochemistry or flow cytometry, cytogenetics and FISH
Imaging as indicated
Multiple Myeloma - Cytogenetics, Interphase FISH, Flow Cytometry - Poor Prognosis
t(4;14)(p16;q32)
t(14;16)(q32;q23)
-17p13
Multiple Myeloma - Cytogenetics, Interphase FISH, Flow Cytometry - Intermediate Prognosis
-13q14
Multiple Myeloma - Types of paraprotein secretion
Complete Ig
Light chain
Both
Non-secretory
Multiple Myeloma - SPEP & UPEP
Monoclonal protein (M-Spike) Gamma globulin SPIKE!!!
MGUS - Criteria for diagnosis
M Protein
Smoldering Myeloma - Criteria for diagnosis
M Protein ≥ 3 g/dL spike
and/or
Monoclonal plasma cells in bone marrow ≥ 10
No end organ damage
Active Myeloma - Criteria for diagnosis
M protein in serum and/or urine
Monoclonal plasma cells in bone marrow ≥ 10^2
≥ 1 CRAB feature (Calcium elevation, renal dysfunction, anemia, bone disease)
CRAB features
Calcium elevation (>11.5 mg/L or ULN) Renal dysfunction (Serum creatinine > 2 mg/dL) Anemia (Hb
Risk of patient with MGUS progressing to active Myeloma
1% per year, so it may take over 20 years.
It really depends on M-spike, though.
MGUS - Management
No therapy alters the natural history of the disease
Repeat studies in 3 - 6 months
If stable, repeat yearly going forward
If low-risk, less frequent follow up can be considered
Bisphosphonates are NOT indicated
Smoldering Myeloma - Management
Deferral of chemotherapy until progression to symptomatic disease
Follow closely every 3 - 4 months with SPEP, CBC, Creatinine & serum calcium
Metastatic bone survey considered annually (asymptomatic bone lesions may develop)
Multiple Myeloma - Stage I
β2M
Mutliple Myeloma - Stage II
Not Stage I or III
Multiple Myeloma - Stage III
β2M ≥ 5.5 mg/L
