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Congenital Neutropenia: Making the Decision to Transplant. John E. Levine, MD, MS University of Michigan Blood and Marrow Transplantation Program. The BMT Process. Step 1: Do you need a transplant? (to be discussed later) Step 2: Finding a donor. Finding a Donor.
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Congenital Neutropenia:Making the Decision to Transplant John E. Levine, MD, MS University of Michigan Blood and Marrow Transplantation Program
The BMT Process • Step 1: Do you need a transplant? • (to be discussed later) • Step 2: Finding a donor
Finding a Donor • Tissue typing (HLA typing) patient, siblings (and parents) • HLA typing: there are proteins are on the surface of cells called HLA molecules • Everyone has their own pattern of these proteins • Typing is done to determine which pattern of these proteins are present in the patient and their potential donors • The pattern is inherited from your parents so siblings are most likely to have the same pattern
Sibling Match Father A1 A3 B7 B44 C5 C7 DR4 DR15 Mother A24 A27 B17 B18 C3 C11 DR3 DR5 Alan A1 A27 B7 B18 C5 C11 DR4 DR5 Brian A3A27 B44B18 C7C11 DR15DR5 Charles A1 A27 B7 B18 C5 C11 DR4 DR5 Diane A3A24 B44B17 C7C3 DR15DR3
What if no family match? • Alternative donors include: • Adult unrelated donors • Unrelated cord blood units • Unrelated donors/Cord blood units: • www.bethematch.org • 13 million donors • ~200,000 cord blood units
Why are more BMT being performed? • Technological advances make BMT safer • New chemotherapy regimens with less toxicity • Better HLA matching techniques • Improved management of infections • Improved management of complications (GVHD)
BMT PROCESS • Chemotherapy to: • Eliminate diseased bone marrow • Prevent rejection of the bone marrow transplant • 5-7 days (given in hospital) • Transplant • Bone marrow is usually collected on day of transplant • Administered through intravenous catheter
BMT COMPLICATIONS • Infections • Relapse (if transplanted for MDS or leukemia) • Graft-versus-host disease • Donor immune system cells try to reject the patient
BMT TIMELINE D-7 to 0 D0 to 14 D14 on Chemo Counts decline Nadir counts Infection, sores, etc Recovery GVHD risk
TREATMENT WITH G-CSF • >90% respond to G-CSF • ANC 1000-1500/μl • Both Ela2 and Hax1 pts equally likely to respond • Long-term G-CSF effects: • headache/bone pain • splenomegaly • osteopenia (28%)
G-CSF RESPONSE Ziedler, BJH, 2008
G-CSF REFRACTORY • High risk of death from infection • 11 patients with no or inadequate response to G-CSF • Myeloablative BMT • Busulfan + cyclophosphamide 120-200 mg/kg • ATG in 4 • Matched sibling donor: 8 • Alternative donor: 3 • Median f/u 2y: 9/11 survived (all 8 sibs) • Additional unpublished data indicates continued good results in G-CSF refractory setting Ziedler, Blood, 2000
G-CSF RESPONSIVE: OUTCOMES • 1990s: increasingly clear that SCN pts were at risk of MDS or AML • 374 patients with SCN registered with SCNIR 11/1987 to 9/2000 • Severe event defined as MDS/AML or sepsis-related death • “Effective” GCSF dose was defined as the dose at 6m • Average ANC from 6-18m was defined as the effective response Rosenberg, Blood, 2006
SEVERE EVENTS 10 y CI: 21% 12 y CI: 36% 10 y CI: 8%
HAZARD RATES MDS/AML p 6y: 2.9%/yr p 12y: 8%/yr Sepsis death: 0.9%/yr
CAN WE PREDICT WHICH PATIENTS ARE AT HIGHEST RISK FOR SEVERE EVENTS?
G-CSF RECEPTOR MUTATIONS • G-CSFR point mutations are common • Present in 30% of pts w/o leukemia • Present in 80% of pts w/ leukemia • Can be present for prolonged periods before leukemia develops (if ever) • Mechanisms leading to leukemia unknown
G-CSF DOSE AND RESPONSE AS PREDICTORS Reference Group: MDS/AML CI @ 10y: 11% Sepsis death CI @ 10y: 4% Overall CI @ 10y: 15%
G-CSF DOSE AND RESPONSE AS PREDICTORS Responders (≥8 µg/kg/d) MDS/AML CI @ 10y: 15% Sepsis death CI @ 10y: 3% Overall CI @ 10y: 18%
G-CSF DOSE AND RESPONSE AS PREDICTORS Weak responders (<8 µg/kg/d) MDS/AML CI @ 10y: 18% Sepsis death CI @ 10y: 7% Overall CI @ 10y: 25%
G-CSF DOSE AND RESPONSE AS PREDICTORS Weak responders (≥8 µg/kg/d) MDS/AML CI @ 10y: 40% Sepsis death CI @ 10y: 14% Overall CI @ 10y: 54%
OPTIMIZING BMT REGIMEN • Univ Michigan pts (n=14) from 1996-2008 • If AML: minimal or no chemo to treat cancer • Busulfan based conditioning + ATG • Target higher stem cell dose to avoid rejection • Augmented infection prophylaxis: • Norfloxacin or levaquin from start of conditioning • Aspergillus coverage (voriconazole) • High survival rate since 2001 (incl last 3 URD)