MDS Flashcards
Common NGS defects in MDS-MLD (multi-lineage dysplasia)
TET2, SF3B1, ASXL1, SRSF2, DNMT3A (also TP53 and ETV)
Issues in the stomach, duodenum, TI and post absorption that may lead to Vitamin B12 deficiency.
a. Stomach: Achlorhydria, gastrectomy/bariatric surgery, H. pylori, PPI, H2 blockers
b. Proximal duodenum: Lymphoma, IBD, pancreatic insufficiency, metformin, celiac, tape worm
c. Terminal ileum: IBD, resection, Imerslund-Gräsbeck
d. Post absorption: Transcobaalamin II deficiency
Others: vegan, pernicious anemia, congenital IF def
Name 4 (adverse) effects of lenalidomide treatment in MDS.
*used in transfusion dependent 5q and some response (~25%) in those with non-5q del,low risk MDS.
Neutropenia ** Anemia Thrombocytopenia ** VTE Infection Diarrhea Rash Fatigue
What are the two cytogenetic abnormalities associated with very good risk MDS?
del Y, del 11q
What are the two cytogenetic abnormalities associated with good risk MDS?
Normal, del 5q, del 12p, del 20q,
What are the two cytogenetic abnormalities associated with intermediate risk MDS?
del7q, Tri 8, i17q, Tri 19, 2 or more ind clones
What are the two cytogenetic abnormalities associated with poor risk MDS?
Abnormal 3q, del 7, double -7/del7q, complex up to 3 abnormalities
What is one cytogenetic abnormality associated with very poor risk MDS?
Complex karyotype with >3 or more abnormalities
MOA of Luspatercept
Erythroid maturation (not production) agent.
- Neutralizes select TGF-B- superfamily ligands to intercept/inhibit SMAD 2/3 signalling
- The reduction in SMAD signaling leads to enhanced erythroid maturation.
BELIEVE trial in Beta- thal, MEDALIST in MDS
Poor prognosis point mutations in MDS?
Poor prognosis: READ T
RUNX1 EZH2 ASXL1 DNMT3A TP53
SF3B1-good outcome
Others: TET2 (better response to AZA), IDH1, IDH2
Which pts are more likely to respond to ESAs in MDS?
- low transfusion requirement (< 2 units/month)
- low endogenous pretreatment plasma EPO level (< 500 U/L)
- < 10% bone marrow blasts
- low/intermediate-1 (int-1) risk International Prognostic Scoring System (IPSS).
*not FDA approved
Why is Rombiplastin not recommended for use in MDS ?
- Increased blast percentage (reversible with holding or stopping)
- Increased progression to leukemia
Explain the process by which ferric iron, bound to transferrin enter the apical membrane of enterocytes.
Fe3+ (ferric) bound to transferrin—> bind to transferrin receptor (TFR1)—> to be stored/transported, it must be reduced to Fe2+ form by Duodenal cytochrome b (Dcytb)–>endocytosis by DMT1 which releases Fe2+ from the Tf-TFR1 complex and escorts to cytoplasm—> Then must be re-converted to Fe3+ before exciting the basolateral membrane into portal circulation via ferroportin.
Causes of isolated elevated homocysteine level
- Folate def
- Hypothyroidism
- Vitamin B6 def (pyridoxine)
4 medications which cause macrocytic anemia?
- MTX
- HU
- 5-FU
- Aziothioprine
5 components of the R-IPSS score in MDS?
BM blast (%) Hemoglobin Plts Anc Cytogenetics
In which MDS pts would you consider allo-SCT?
- R- IPSS intermediate-, high-, or very-high-risk disease at diagnosis
- Progressing to advanced MDS
- Patients with lower-risk disease but failing supportive care with growth factors, IST, and/or hypomethylating agents.
Define idiopathic cytopenia of undetermined significance (ICUS)
Cytopenia in one or more blood lineages that remain unexplained despite appropriate evaluation, as described separately.
●No evidence of clonal hematopoiesis (CH); if a leukemia-associated mutation is detected, the variant allele frequency (VAF) should be <2 percent.
●No other evidence of a hematologic malignancy, according to World Health Organization (WHO) criteria.
Define CHIP (clonal hematopoiesis of indeterminant potential)
●VAF ≥2 percent of an acquired mutation of a leukemia-associated gene; the most common mutations affect DNMT3A, TET2, and/or ASXL1, but other recurrently mutated genes can be seen (JAK2, TP53)
●Normal peripheral blood counts. The diagnosis of CHIP specifically excludes patients with clinically significant cytopenias; such patients should instead be diagnosed with clonal cytopenia of uncertain significance (CCUS).
●No clinical or pathologic evidence for a World Health Organization (WHO)-defined hematologic malignancy.
A bone marrow examination is not required to diagnose CHIP, but it may be performed to exclude a hematologic malignancy, as described above
10% of adults >70 yrs (higher if prior chemo/rad)
-Higher mortality and CVD risk, increases the risk of developing therapy-related myeloid neoplasm
Define clonal cytopenia of undetermined significance (CCUS)
VAF ≥2 percent of an acquired mutation of a leukemia-associated gene.
Cytopenia – Unexplained cytopenia (ie, below the lower limit of normal for that laboratory) of at least one blood lineage, after an appropriate evaluation, as described separately.
No clinical or pathologic evidence for a WHO-defined hematologic malignancy neoplasm
Name 2 MDS/MPN overlap syndrome.
- CMML
- MDS/ MPN with ring sideroblasts and thrombocytosis (which requires a platelet count ≥450 × 109/L).
- JMML
- Atypical CML
Two morphologic features of 5q- MDS. What sex is it more common in?
- Hypolobated megakaryocytes
- Erythroid hypoplasia
- Giant platelets (count can be N or high)
More common in women. Low rate of leukemic transformation. Does not respond to G-CSF.
2 molecular tests you may consider in a pt with MDS which would help with prognostication?
- SF3B1 (good prognosis), common in MDS-RS. Use luspatercept.
- TP53
Name 2 factors that confer poor prognosis in MDS that are not captured in the R-IPSS.
- Evidence of iron overload (even if low risk)
2. Transfusion frequency <8 weeks
3 predictors of response to IST in MDS patients other than hypocellularity.
Therapy is with ATG and CycA
- Low risk disease (<10% blasts)
- <60 years
- Transfusion independent
- Normal karyotype
- Trisomy 8
Pt with vit B12 def, newly started on Tx:
b. How long until retics go up?
c. How long until macrocytosis improves
d. How long until neuro symptoms improve
b. How long until retics go up? Within hours; peak reticulocyte count within 1 week. c. How long until macrocytosis improves 2-3 months (together with Hb) d. How long until neuro symptoms improve 3-12 months. May be permanent
5 common mutations seen in CMML?
- NRAS
- KRAS
- ASXL1
- TET2
- SRSF2
- CBL