Plasma Cell Dyscrasias - Harrington Flashcards
What is the characteristic nuclear morphology seen histologically in plasma cells?
Clock-face chromatin
How do we differentiate reactive vs. neoplastic conditions with B cells?
How might this be detected?
Clonality -> gives evidence of neoplasia
Methods: monoclonal antibodies in the urine, light-chain identification via flow cytometry of immunohistochemistry, immunophenotypic aberrancy (example: CD56 on plasma cells)
Define: Bence Jones Protein
free light chains, may be found in the urine
What is the most common plasma cell neoplasm?
Multiple myeloma
Describe the epidemiology of multiple myeloma
15% of all heme malignancies in the US
Males > Females
AAs > Caucasians
50-70 y/o (median 68-70)
Name the three major diagnostic criteria for multiple myeloma
- Clonal plasma cells
- M protein
- End organ damage
What end-organ damage is seen with multiple myeloma? (Hint: mnemonic)
CRAB
hyperCalcemia
Renal insufficiency
Anemia
Bone disease
Why is it important to obtain electrophoresis of both the urine **and **the serum when diagnosing multiple myeloma?
99% of myelomas have M protein or Bence Jones protein, but they don’t always appear together nor in both locations.
60-70% have serum M protein **and **Bence Jones proteins
20% have only Bence Jones proteins
In the setting of kidney disease, the Bence Jones proteins may only appear in the urine (due to hyperfiltration of the serum)
What is the most common site of lytic bone lesions in multiple myeloma?
Vertebrae (66%)
Ribs (44%)
Skull (41%)
Pelvis (28%)
Femur (24%)
Name some common forms of end organ damage seen in multiple myeloma
Which is the most common cause of death in MM?
Lytic bone lesions (bone pain, pathologic Fx, osteopenia)
Hypercalcemia (secondary to bone resorption)
Renal insufficiency (direct nephrotox, tubular casts, amyloidosis, etc)
Anemia (rouleaux = stacks/aggregates of RBCs, renal disease, bone marrow invasion)
Immunosuppression (normal Ig suppressed by M proteins -> recurrent infections -> most common cause of death)
Describe the general prognosis of multiple myeloma
What is the general treatment approach?
Incurable
Median **treated **(!!!) survival: 4-6 years
treatment: systemic chemotherapy and two (“tandem”) autologous bone marrow transplants
What is a plasmacytoma?
What is its relationship to MM?
Localized growth of monoclonal plasma cells
It may be associated with MM, or appear as a distinct entity
By iteself: no clonal expansion in bone marrow, +/- M protein
What is the general treatment approach for plasmacytoma?
Localized: radiation
Systemic (w/ MM): chemo + BMT
Where do plasmacytomas usually occur?
Solitary plasmacytoma of bone
Extramedullary plasmacytoma (80% in URT)
What is Waldenstrom’s macroglobulinemia?
Characteristic of lymphoplasmacytic lymphoma
- Visual/neurologic impairment
- Cryoglobulinemia
- Raynaud phenomenon
- Bleeding