4. ā¢ Electrophoretic analysis permits separation of
components of the serum proteins.
ā¢ The immunoglobulins move heterogeneously
in an electric field and form a broad peak in
the gamma region, which is usually increased
in the sera of patients with plasma cell
tumors.
ā¢ There is a sharp spike in this region called an
M component (M for monoclonal).
5.
6. ā¢ The monoclonal antibody must be at least 5
g/L (0.5 g/dL) to be accurately quantitated by
this method. This corresponds to ~109 cells
producing the antibody.
ā¢ M component an excellent tumor marker to
manage therapy, yet it is not specific enough
to be used to screen asymptomatic
9. ā¢ In ~20% of myelomas, only light chains are
produced and, in most cases, are secreted in
the urine as Bence Jones proteins.
ā¢ IgG myelomas are more common than IgA and
IgD myelomas.
11. ā¢ a malignant proliferation of plasma cells
derived from a single clone.
ā¢ cause of myeloma is not known
ā¢ More in nuclear radiation exposure
ā¢ More in farmers, wood workers, leather
workers, and those exposed to petroleum
products.
ā¢ N-ras, K-ras, and B-raf mutations are most
common and combined occur in over 40% pts
12. ā¢ The neoplastic event in myeloma may involve
cells earlier in B-cell differentiation than the
plasma cell. Interleukin (IL) 6 may play a role
in driving myeloma cell proliferation.
13. INCIDENCE & PREVALENCE
ā¢ The median age at diagnosis is 70 years; it is
uncommon under age 40.
ā¢ Males are more commonly affected than
females, and blacks have nearly twice the
incidence of whites.
14. PATHOGENESIS
ā¢ Multiple myeloma (MM) cells bind via cell-
surface adhesion molecules to bone marrow
stromal cells (BMSCs) and extracellular matrix
(ECM), which triggers MM cell growth,
survival
15. ā¢ induction of various cytokines, including IL-6,
insulin-like growth factor type I (IGF-I),
vascular endothelial growth factor (VEGF), and
stromal cellāderived growth factor (SDF)-1Ī±.
ā¢ Growth, drug resistance, and migration are
mediated via Ras/Raf/mitogen-activated
protein kinase, PI3K/Akt, and protein kinase C
signaling cascades, respectively
19. ā¢ SUSCEPTIBILITY TO BACTERIAL INFECTIONS
ā¢ most common infections: pneumonias and
pyelonephritis.
ā¢ Streptococcus pneumoniae, Staphylococcus
aureus, and Klebsiella pneumoniae in the
lungs
ā¢ Escherichia coli and other gram-negative
organisms in the urinary tract
21. ā¢ Renal failure: Hypercalcemia is the most
common cause
ā¢ Glomerular deposits of amyloid,
hyperuricemia, recurrent infections, frequent
use of nonsteroidal anti-inflammatory agents,
iodinated contrast dye for imaging,
bisphosphonate use, and occasional
infiltration of the kidney by myeloma cells all
may contribute to renal dysfunction.
31. ā¢ Non-IgG subtype, abnormal kappa/ lambda
free light chain ratio, and serum M protein
>15 g/L (1.5 g/ dL) are associated with higher
incidence of progression of MGUS to
myeloma.
32. higher risk of progression from SMM
to MM
ā¢ bone marrow plasmacytosis >10%,
ā¢ abnormal kappa/lambda free light chain ratio,
ā¢ serum M protein >30 g/L (3 g/dL).
33.
34.
35. ā¢ Serum calcium, urea nitrogen, creatinine, and
uric acid levels may be elevated.
ā¢ Protein electrophoresis and measurement of
serum immunoglobulins and free light chains are
useful for detecting and characterizing M spikes,
supplemented by immunoelectrophoresis.
ā¢ A 24-h urine : quantitate Bence Jones protein
excretion.
ā¢ Serum alkaline phosphatase is usually normal
41. ā¢ Thalidomide (200 mg daily) with
dexamethasone
ā¢ lenalidomide (25 mg/d on days 1ā21 every 4
weeks), and bortezomib (1.3 mg/m2 on days
1, 4, 8, and 11 every 3 weeks),combined with
dexamethasone (40 mg once every week) :
42.
43. ā¢ In patients who are transplant candidates,
alkylating agents such as melphalan should be
avoided because they damage stem cells.
44. ā¢ Improvement in the serum M component may
lag behind the symptomatic improvement
ā¢ Light chain excretion, with a functional half-
life of ~6 h, may fall within the first week of
treatment.
ā¢ Allogenic transplantation
ā¢ Maintenance therapy prolongs remissions
following standard dose regimens as well as
HDT
45. ā¢ Relapsed myeloma : lenalidomide and/or
bortezomib. These combination with
dexamethasone : response rate of up to 60% and
a 10ā15% complete response rate in patients
with relapsed disease.
ā¢ The combination of bortezomib and liposomal
doxorubicin is active in relapsed myeloma.
ā¢ Thalidomide, if not used as initial therapy, can
achieve responses in refractory cases.
ā¢ The second-generation proteasome inhibitor
carfilzomib and immunomodulatory agent
pomalidomide
ā¢ High-dose melphalan and stem cell
transplantation
46.
47. ā¢ Prophylactic administration of intravenous Ī³
globulin preparations is used in the setting of
recurrent serious infections.
ā¢ The anemia associated with myeloma may
respond to erythropoietin along with
hematinics
48. WALDENSTROMS
MACROGLOBULINEMIA
ā¢ associated with lymphadenopathy and
hepatosplenomegaly, but the major clinical
manifestation was hyperviscosity syndrome.
ā¢ originates from a postā germinal center B cell
that has undergone somatic mutations and
antigenic selection in the lymphoid follicle and
has the characteristics of an IgM-bearing
memory B cell.
49. ā¢ Familial occurance common
ā¢ MYD88 L265P somatic mutation
ā¢ molecular pathogenesis of the disease, with
involvement of Toll-like receptor (TLR) and
interleukin 1 receptor (IL-1R) signaling.
ā¢ activation of IL-1Rāassociated kinase (IRAK) 4
and IRAK1 followed by nuclear factor-ĪŗB (NF-
ĪŗB) activation.
50. ā¢ develop a peripheral neuropathy
ā¢ half of these patients are positive for anti-
MAG antibody. The neuropathy may precede
the appearance of the neoplasm.
ā¢ IgM in some patients with macroglobulinemia
may have specificity for myelin-associated
glycoprotein (MAG),
51.
52.
53. TREATMENT
ā¢ Plasmapheresis For hyperviscosity symptoms
ā¢ Median survival of affected individuals is ~50
months.
ā¢ Bortezomib and bendamustine are two agents
with significant efficacy in WM.
ā¢ Rituximab (anti-CD20) can produce responses,
alone or combined with either of these two
agents
54. ā¢ Fludarabine (25 mg/m2 per day for 5 days
every 4 weeks) and cladribine (0.1 mg/kg per
day for 7 days every 4 weeks) are also highly
effective single agents.
ā¢ With identification of the MYD88 mutation,
BTK and IRAK1/4 inhibitors are being
evaluated and show significant responses.
59. ā¢ diagnosis depends on the demonstration of an
anomalous serum M component (often <20
g/L [<2 g/dL]) that reacts with anti-IgG but not
antiālight chain reagents.
ā¢ The M component is typically present in both
serum and urine. Most of the paraproteins
have been of the Ī³1 subclass
ā¢ Therapy is indicated when symptomatic and
involves chemotherapeutic combinations used
in lowgrade lymphoma. Rituximab has also
been reported to show efficacy.
60. ALPHA HEAVY CHAIN DISEASE
(SELIGMANNāS DISEASE)
ā¢ Mc heavy chain disease
ā¢ Closely related to meditteranean lymphoma
ā¢ infiltration of the lamina propria of the small
intestine with lymphoplasmacytoid cells that
secrete truncated alpha chains.
ā¢ Demonstrating alpha heavy chains is difficult
because the alpha chains tend to polymerize
and appear as a smear instead of a sharp peak
on electrophoretic profiles
61. ā¢ Light chains are absent from serum and urine.
ā¢ patients present with chronic diarrhea, weight
loss, and malabsorption and have extensive
mesenteric and paraaortic adenopathy.
Respiratory tract involvement occurs rarely
ā¢ Chemotherapy plus antibiotics may be more
effective than chemotherapy alone.
62. ā¢ Immunoproliferative small-intestinal disease
(IPSID) is recognized as an infectious
pathogenāassociated human lymphoma that
has association with Campylobacter jejuni.
ā¢ It involves mainly the proximal small intestine
resulting in malabsorption, diarrhea, and
abdominal pain.