Plasmacytoma and Multiple Myeloma Flashcards
difference between plasmacytoma and multiple myeloma
plasmacytoma is a plasma cell neoplasm of the soft tissue or bones and is a solitary lesion while multiple myeloma is a systemic plasma cell neoplasm
margins plasmacytoma extra medullary
common for there to be a large margin to encompass the the lymphatics are there is a higher propensity for LN to be involved than in plasmacytma of the bone
Plasmacytomas are _% solitary bone lesions and ___% extramedularry (soft tissue tumours)
80% solitary bone primaries and 20% extra medullary soft tissue tumours
solitary plasmacytomas of the bone are most often located where?
vertebral bodies or pelvic bones, most pf these tumours end up developing into multiple myeloma
where do most extra medullary plasmacytomas occur?
80% occur in the upper aerodigestive tract (nasal cavity, paranasal sinuses, pharynx, larynx, tonsils)
what type of plasmacytoma most frequently becomes multiple myeloma?
Osseous plasmacytoma becomes multiple myeloma in 50-80% of cases and extramedularry plasmacytoma becomes multiple myeloma in 10-40% of cases
GTV, CTV margins for plasmacytoma
GTV+2-3cm=CTV
CTV+.5-1cm=PTV
When is IMRT most often used in the treatment of plasmacytoma? what is used when this is not the case?
IMRT is used when the PTV is close to a critical structure (this is more common in extra medullary plasmacytoma for ex: when the paranasal sinuses are treated we use IMRT to avoid treating the optics) Otherwise a POP is most often used
Most common presentation for plasmacytoma ?
bone pain in 70% of cases as most plasmacytomas are single bone plasmytomas (80%)
Secretions found in presentation of plasmacytomas/ multiple myelomas
Secrete measurable paraprotein in 99% of cases, Imuunoglobin G found in 50-60% of cases and Immunoglobin A found in 20-25% of cases
Indications that a plasmytoma will progress into a multiple myeloma
- Bony subtype
- Greater age is more likely to progress into multiple myeloma
- subclinical bone disease is more likely to develop intto multiple myeloma
- if there is a high level of M protein post XRT there is a higher likelihood of developing into multiple myeloma
standard treatment for plasmacytoma
-XRT
doses for plasmytoma
35-45Gy
surgery in plasmytoma
surgery is used ALONE for small extra medullary plasmyctomas and is used for bone plasmacytomas for structurally unstable bone or RAPIDLY PROGRESSIVE emergencies such as SCC and is followed by XRT
small vs large extra medullary plasmacytomas treatment
small may be curatively removed and treated with surgery alone, large may be treated with XRT alone
Chemotherapy in plasmacytoma
used adjuvantly after XRT and given for 3 years
chemo agents in plasmacytoma
melphalen and prednisone
major and minor diagnosis criteria for Multiple Myeloma
need to have at least one major and one minor criteria or 3 minor criteria is required to make a MM diagnosis.
Major: -plasmycytoma on tissue biopsy
-BM plasmycytosis with 30%plasma cells
-monoclonal immunoglobulin spike >3,5g/dL
Minor criteria:
-BM plasmacytosis between 10-30% plasma cells
-lytic bone lesions
-monoclonal immunoglobulin spike but with levels lower than 3.5g/dL
most common presentation for MM
bone pain and fatiguability
what presentation on lab tests are common on MM
- anemia
- granulocytopenia (low granulocytes)
- thrombocytopenia (low platelet count)
- abnormal monoclonal immunoglobin levels
Whats MGUS? What clinically demonstrates MGUS?
MGUS is monoclonal gammopathy of unknown significance- it is a precancerous MM condition. Its clinically significant features are:
monoclonal protein is <3g/dL
Bone marrow clonal plasma cells are <10% with no organ related dammage
types of MM and severity
MGUS -monoclonal gammopathy of unknown significance, is a precancerous condition with a low propensity to become MM
Asymptomatic MM- intermediate form of MM, has a 20% of risk per year of becoming MM higher propensity than MGUS
Plasma cell leukemias- very rare and very severe variant of MM
causes MM
prior XRT exposure
exposure to petroleum
preceded by MGUS
Adverse prognostic indicators for MM Platelet count serum albumin serum creatinine b2 micoglobulin hemoglobin bone marrow plasma percentage
Platelet <150,000/uL serum albumin <3g/dL serum creatinine >2g/dL b2 microglobulin >4mg/dL hemoglobin >10g/dL bone marrow plasma percentage >50%
