Bone Marrow Transplant Flashcards
Bone Marrow Transplant
Give a patient a toxic drug and then give the patient stem cells can potentially help them recover their marrow and give them the best change to get rid of the cancer
Hematopoietic Stem Cells are responsible for:
producing all of the cellular components for the blood
Define Hematopoietic Stem Cell Transplant
Procedure in which HSCs are removed from donor and infused into a recipient (donor and recipient may be same person)
HSC Lineage
Myeloid: what you see in the blood
Lymphoid: B cells and T cells
Stem Cells + Lineage
- Can choose to go down the myeloid or lymphoid lineage and then it will commit
- It can also divide itself and continue to grow themselves within the marrow without losing their stem cell properties
What are the ideal stem cells?
CD34 cells
Indications for HSCT
Mostly hematologic cancers like leukemia, lymphomas, myelodysplastic syndrome, multiple myeloma and beta thalassemia
Autologous Indications
Multiple Myeloma
Non-Hodgkin’s lymphoma
Hodgkin’s lymphoma
Allogeneic Indications
AML
Acute lymphoblastic leukemia
CML
3 sources of Stem Cells
o Bone Marrow
o Peripheral Blood Stem Cells (PBSC)
o Cord Blood
Where is 95% of the marrow?
Ileac crest in the hip area
Very painful removal
Bone Marrow Removal
o Multiple punctures/aspirations to get enough stem cell for transplantation
Peripheral Blood Stem Cells
Collected by apheresis
o Giving a patient chemotherapy or specialized growth factor(such as GMCSF) at high doses (10-15mg/kg) to push the stem cells out into the peripheral blood
o Hook up to a machine to collect CD34 cells
Cord Blood Stem Cells Process
o Consent donors → separate placenta → collect umbilical cord blood → isolate stem cells into 20 mL and 5 mL DMSO → overwrap 25 mL PCB unit and place in canister → Insert PCB unit into CRF module → Initiate automatic CRF and archival of PCB unit
Cord Blood Stem Cells Amount
Very small amount but very rich in stem cells
Less risk of GVHD
Autologous BMT Donor and Recipient
Donor and recipient are the same
Autlogous BMT Use
Primarily as a means to dose escalate
Infusion of autologous stem cells serves to rescue the patient from the myelosuppressive effects of high dose chemotherapy
Allogenic Donor and Recipient
Donor: non-cancer person
Recipient: cancer person
Allogenic BMT Use
To replace missing hematopoietic or lymphoid component in aplastic anemia or immune disorders
To rescue the recipient from myeloablative therapy for treatment of malignant disease
Define Graft-Versus-Tumor-Effect
• The donor cells actually attack the tumor cells and help get rid of it through immune response (improved outcome for that cancer)
Autologous SCT Advantages
Availability
Able to perform in older patients
No GVHD
Autologous SCT Disadvantages
Risk of reinfusion of disease
No GVT effect
Autologous BMT in what Cancer
Lymphomas
Multiple myeloma
Solid tumors
Allogenic SCT Advantages
No risk of reinfusion
GVT effect
Allogenic SCT Disadvantages
Availability
GVHD
Who is the best donator for allogenic SCT?
Sibilings
General Characteristics of Acceptable Donors?
Minimal co-morbidities Capable of tolerating collection Negative for HIV, Hepatitis B, and Hepatitis C No current malignancies Willing to provide consent 18-30 years old Less pregnancies
Matched Related Donors
Only requires an antigen match at HLA-A, B, and DR (6/6)
Matched sibling donors (MSD) are the preferred donor
Unmatched Related Donors
Typically haploidentical donors (parents)
Only considered out of necessity
Matched Unrelated Donors
Requires allele matches (HLA-A, B, C, DR, and DQ (10/10))
May require up to 6 months
Class I Region of HLA
All nucleated cells
HLA A/B/C
Class II Region of HLA
Immune System Cells
HLA-DR/DQ
Course of BMT
Mobilize cells → collect cells → store cells → conditioning → transplant → post-BMT period → Engraftment
Define Conditioning
High dose chemotherapy to wipe out patient’s marrow of normal cells and cancer cells
Post-BMT Period
Stem cells will take 7-21 days to make new stem cells and to differentiate into other cells
High risk of infection
High risk of bleed
Chemo-radio therapy side effects
Define Engraftment
Hemoglobin, WBC and platelets are normalized
Options for Mobilization Regimen
Myelosuppressive chemotherapy with or without CSFs
CSFs alone (G-CSF or GM-CSF)
Plerixafor – prevents stem cells from staying in the bone marrow
Allogeneic Course Differences
GVHD and risk of infection
Allogeneic Risk of Infection
Can try to prevent
Early: gram negative/positive, candida, aspergillus, HSV
Mild (2-3months post): same + CMV/PJP
Late (>3 months post): varicella zoster, mold, PJP