Diagnostic Scoring Systems for MDS
Diagnosing myelodysplastic syndromes (MDS) is a complex and lengthy process
that involves first ruling out other causes for reported symptoms. Myelodysplasia
may result from vitamin deficiencies and viral infections, as well as from
antibiotic use, chemotherapy, or exposure to ethanol or benzene. Consequently,
diagnosis requires detailed patient histories, physical examinations, laboratory
testing, and extensive blood counts and analyses.1
The most effective diagnostic tools, however, are bone marrow biopsies and
analyses. These examine the morphologies of marrow and blood cells, which provide
definitive diagnostic information. Dysplastic cells often are misshapen and
have visibly abnormal chromosomes, and a finding of abnormal chromosomes in
the marrow indicates neoplasia.1 The most common cytogenetic abnormalities
are a loss or gain of part or all of chromosomes 5, 7, 8 and 20.1
Once a diagnosis of MDS is achieved, the International Prognostic Scoring
System (IPSS) will be applied to determine the patient’s likelihood of
progressing to acute myeloid leukemia (AML) and having a shortened life expectancy.3 The
IPSS uses blood and marrow findings to stratify risks
and predict outcomes; specifically, its predictive criteria are the percentages
of blasts, the karyotype and the number of cytopenias.2
A lower score indicates a lower risk and a higher score indicates a higher
risk. In general, the more cytopenias, blasts and cytogenetic abnormalities
the patient has, the worse the prognosis, as the IPSS shows.2
- Low-Risk Group (IPSS Score 0): About half of the patients will
survive 5.7 years, and 25% of the patients will progress to AML within 9.4
years.
- Intermediate-Risk Group 1 (IPSS Score 0.5-1.0):About half
of the patients will survive 3.5 years, and 25% of the patients will progress
to AML within 3.3 years.
- Intermediate-Risk Group 2 (IPSS Score 1.5-2.0): About half of
the patients will survive a year, and 25% of the patients will progress to
AML within a year.
- High-Risk Group (IPSS Score
2.5): About half of the patients
will survive 4.5 months, and 75% of the patients will progress to AML.3
References
- Heaney ML, Golde DW. Myelodysplasia. N Engl J Med 1999; 340:1649-60.
- Aplastic Anemia & MDS International Foundation, Inc. Myelodysplastic
Syndromes: Basic Explanations. Aplastic Anemia & MDS International
Foundation, Inc. Annapolis, MD; 2005:1-19.
- Kouides PA, Bennett JM. Understanding Myelodysplastic Syndromes: A Patient
Handbook. MDS Foundation 2005, http://www.mds-foundation.org/patientinfo.htm.
