Hypocellular Myelodysplastic Syndrome
Definition
- Myelodysplastic syndrome with decreased marrow cellularity
Diagnostic Criteria
- Exclusions
- Non-clonal causes for dysplasia must be excluded (see Differential Diagnosis)
- If chemotherapy or radiation therapy related, should be reported as "therapy-related myeloid neoplasm"
- <1 x103/μL monocytes (if present consider Chronic Myelomonocytic Leukemia)
- Lack of neutrophilia (if present consider BCR-ABL1+CML or atypical CML)
- Decreased bone marrow cellularity
- <30% if age 60 or under
- <20% if over 60
- Occurs in 5-10% of MDS patients
- More frequent in women
- Hypocellular MDS presents special differential diagnostic problems
- Distinction between various MDS may be compromised by decreased cellularity but should be made, if possible, based on standard criteria:
Myelodysplastic Syndromes
Circulating Blasts | Marrow Blasts | Ring Sideroblasts | Dysplastic Lineages | Cytopenias | |
---|---|---|---|---|---|
RCUD | <1% | <5% | <15% | Any 1 lineage | 1 or 2 |
RARS | 0 | <5% | ≥15% | Only erythroid | 1 or 2 |
RCMD | <1% | <5% | Variable | 2 or more lineages | 1, 2 or 3 |
<5% | 5-9% | Variable | 1 or more | 1, 2 or 3 | |
5-19% | 10-19% or Auer rods | Variable | 1 or more | 1, 2 or 3 | |
del(5q) | <1% | <5% | Variable | Frequently hypolobated small megakaryocytes | Usually 1 (anemia) |
- RCUD = refractory cytopenia (anemia, neutropenia or thrombocytopenia) with unilineage dysplasia; RARS = refractory anemia with ringed sideroblasts; RCMD = refractory cytopenia with multilineage dysplasia; RAEB = refractory anemia with excess blasts; del(5q) = 5q- syndrome
- All MDS must not have absolute monocytosis
- If present, consider chronic myelomonocytic leukemia
- If chemotherapy or radiation therapy related, should be reported as "therapy-related myeloid neoplasm"
- In children, consider provisional WHO entity "refractory cytopenia of childhood" for low blast count MDS
- Myelodysplastic syndrome unclassifiable (MDS-U)
- Must not meet criteria of any specific WHO category
- Persistent cytopenia(s) with any of the following:
- Unilineage marrow dysplasia with pancytopenia OR
- <1% blasts in blood, <5% blasts in marrow and cytogenetic abnormalities but no lineage with ≥10% dysplastic forms OR
- Findings of RCUD or RCMD but with 1% blasts in peripheral blood
- (2-4% blasts would be classified as RAEB-1)
- Nonclonal causes must be excluded
Dita Gratzinger MD PhD
Tracy I George MD
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342
Original posting: 10/23/11