How Are Myelodysplastic Syndromes Scored?

Doctors often group cancers into different stages based on the size of the tumor and how far the cancer has spread from the original site in the body. The stage of a cancer can help predict the outlook for a cancer. Often, the cancer’s stage is used to decide which treatment is needed.

However, myelodysplastic syndromes (MDS) are diseases of the bone marrow. They cannot be staged by looking at the size of a tumor like some other cancers. Other factors are used to predict outlook and determine the need for treatment. These factors include the patient’s blood counts, the appearance of their bone marrow, their age, and certain chromosome changes.

International Prognostic Scoring System

The International Prognostic Scoring System (IPSS) is a system developed for staging MDS. It was intended for use with the FAB classification system. It rates 3 factors:

  • The percentage of blasts in the bone marrow (scored on a scale from zero to 2)
  • Chromosome abnormalities (scored from zero to 1)
  • The patient’s blood counts. (scored as zero or 0.5)

Each factor is given a score, with the lowest scores having the best outlook. Then the scores for the factors are added together to make the IPSS score. The IPSS puts people with MDS into 4 groups:

  • Low risk
  • Intermediate - 1 risk (Int-1)
  • Intermediate - 2 risk (Int-2)
  • High risk

WHO Prognostic Scoring System (WPSS)

More recently, a scoring system was developed based on 3 factors:

  • The type of MDS based on the WHO classification
  • Chromosome abnormalities
  • Whether or not the patient requires blood transfusions

    No points

    1 point

    2 points

    3 points

    WHO type

    RA, RARS, (del)5q










    Needs Transfusions




This system puts patients with MDS into 5 groups

  • Very low risk (score = 0)
  • Low risk (score = 1)
  • Intermediate (score = 2)
  • High risk (score = 3 or 4)
  • Very high risk (score = 5 or 6)

These risk groups can also be used to predict outlook (see the next section)

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Our team is made up of doctors and master’s-prepared nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Last Medical Review: February 10, 2014 Last Revised: July 2, 2015

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