Hematopoietic Transplantation

Question 1

What are the different types of transplant?

Answer 1

• Autologous: self to self Syngeneic: from genetically identical twin
• Do not use for cancer because the identical twin’s cells will not recognize cancer as bad Allogenic
• Matched sibling
• Matched unrelated donor
• Haploidentical donor
• Cord blood Advantages:
• Graft vs tumor = cure …donor immune response against malignant cells Disadvantages
• Greater mortality
• GVHD
• Infections
• Graft rejection
• Xenogeneic: from another species

Question 2

What is the purpose of hematopoietic transplants?

Answer 2

• Replacement therapy Ablative therapy
• Allows dose escalation of chemotherapy and radiation to “super-intensive” levels in order to achieve the best chance of tumor kill Immunotherapy
• Graft versus tumor effect (new immune system)
• Gene therapy

Question 3

Explain the details of the procedure of hematopoietic stem cell transplant

Answer 3

Sources of stem cells: bone marrow, peripheral blood, cord blood

• Use colony stimulating factor (G-CSF) to help get more stem cells in the peripheral blood Cord blood
• Superior proliferative capacity will compensate for low cell dose
• Naïve immune system -> reduced GVHD -> extension of donor pool
• Unlimited supply, rapid availability

Question 4

Conditioning regimen

Answer 4

• Patients have to respond to chemo to go to a stem cell transplant
• CHOP -> ICE -> BEAM (beam is the ablative)
• If the patient does not respond to ICE, cannot move to BEAM

Question 5

What are the indications for SCT

Answer 5

Indications for Autologous Transplantation Non-Hodgkin’s lymphoma
* High grade diseases
* Salvage for relapsed DLBCL disease Hodgkin’s Disease
* Salvage for relapsed disease Multiple myeloma
* First line therapy in transplant eligible patients
* Improves survival
Indications for Allogenic Transplantation AML
* All intermediate or high risk patients ALL
* Philadelphia + ALL CML
* Controversial now with Imatinib Refractory Non-Hodgkin’s disease
* Refractory or transformed indolent lymphomas Aplastic anemia
* <20 ys
* Consider for 20-40 ys with match sibling Non-malignant
* Thalassemias, sickle cell Other severe Myeloproliferative disorders
* Younger patients with match with severe disease Myelodysplastic syndrome
* Advanced disease with match donor

Question 6

What is a mini transplant?What are its associated advantages?

Answer 6

Mini transplant

• Decrease intensity of the chemo
• Do not need ablative therapy
• Let the donor cells slowly replace the host cells and also combat the tumor
• Use for: elderly, diabetes, previous transplantation
• The recipient to donor switch is a slow process and significant graft vs. tumor effect may not be evident until 2-3 months. Hence, patients with aggressive disease or active leukemia may not be a suitable candidate for this modality

Question 7

Ablative therapy.

Answer 7

Stem cells are normal, we collect the stem cells first and then ablate the bone marrow and then reinfuse the stem cells.Stem cells have to be normal, cant be done for aplastic anemiaAllogenic transplant is used in refractory cases when they are chemo resistantSyngenic doesnt lead graft vs host disease, so the graft vs tumor positive effect wouldnt be seen eitherNumber one complication of autologous transplantation is relapseHematologic malignanciesthat can be treated with autologous transplant are MM, NHL and Hodgekin lymphoma