Multiple Myeloma

Question 1

what is a multiple myeloma?

Answer 1

neoplasm of antibody secreting B cells (plasma cells)

Question 2

what are plasma cells?

Answer 2

terminally differentiated B cells that secrete antibodies

Question 3

immunophenotype of plasma cells

Answer 3

CD19+, CD138+, CD56-

Question 4

where do normal plasma cells reside?

Answer 4

lymph nodes and bone marrow

Question 5

morphologic features of normal plasma cells

Answer 5

eccentric nuclei, clumped clockface nuclear chromatin, perinuclear clear zone for golgi, abundant gray cytoplasm

Question 6

CD138

Answer 6

syndecan. indicative of plasma cells

Question 7

CD56

Answer 7

NCAM. cell adhesion molecule expressed by neoplastic plasma cells. allows them to home in on bone marrow rather than accumulate in medullary zone of lymph nodes

Question 8

epidemiology of multiple myeloma

Answer 8

common in african americans, affects age 70+,

Question 9

clinical features of multiple myeloma

Answer 9

multifocal, osteolytic lesions and successive fractures, trabecular destruction leading to hypercalcemia, anemia via marrow destruction and renal failure (EPO)

Question 10

where are the osteolytic lesions of multiple myeloma most commonly found?

Answer 10

axial skeleton, particularly the vertebrae/ribs/skull

Question 11

soft tissue tumors of multiple myeloma

Answer 11

plasmacytomas. commonly found in vertebral column, which is an emergency since they cause cord compression

Question 12

morphology of multiple myeloma

Answer 12

hyper cellular marrow: clusters or sheets of monoclonal plasma cells, replacement of marrow elements, destruction and resorption of bone. VARIABLE MORPHOLOGY

Question 13

flame cell

Answer 13

IgA expressing plasma cells with pink border

Question 14

Mott cells

Answer 14

look bubbly. have accumulated globules of intracytoplasmic monoclonal Ig

Question 15

M protein/paraprotein

Answer 15

unique homogenous monoclonal Ig secreted by plasma cells

Question 16

MGUS

Answer 16

monoclonal gammopathy of undetermined significance. low grade asymptomatic proliferation that isn’t clearly neoplastic. most likely won’t progress to multiple myeloma, but some do

Question 17

what can the kidney filter in terms of Ig?

Answer 17

light chains can pass through the glomerulus

Question 18

difference in Ig production of normal and neoplastic plasma cells

Answer 18

neoplastic cells: unbalanced production–> excess light or heavy chains.

Question 19

Bence Jones Protein

Answer 19

excess light chains in urine. can be used to diagnose multiple myeloma

Question 20

most common paraproteins

Answer 20

IgG and kappa

Question 21

why are patients with multiple myeloma immunodeficient and anemic?

Answer 21

increase in monoclonal Ig leads to a decrease in other types. Same goes for types of cells in the bone marrow

Question 22

name for immunodeficiency of multiple myeloma

Answer 22

humoral immune paresis

Question 23

two main causes of deaths in MM patients

Answer 23

immunodeficiency (recurrent bacterial infections) & renal failure (myeloma kidney)

Question 24

myeloma kidney

Answer 24

due to cast nephropathy, proximal tubulopathy, hypercalcemia, amyloidosis

Question 25

cast nephropathy

Answer 25

excess light chains settle out in aggregates in the distal nephron, forming obstructive casts

Question 26

consequences of paraprotein

Answer 26

serum hyper viscosity with rouleaux formation. causes vascular complications like visual impairment, neurological problems, and bleeding. Cryoglobulinemia (Raynauds phenomenon), amyloidosis.

Question 27

MM prognosis

Answer 27

variable (1-many years) without a cure