Categories D37-D44, and D48 classify by site neoplasms of uncertain behavior, i.e., histologic confirmation whether the neoplasm is malignant or benign cannot be made.


  • neoplasms of unspecified behavior (D49.-)
  1. D46 Myelodysplastic syndromes

    Use Additional code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5)


    • drug-induced aplastic anemia (D61.1)
    1. D46.0 Refractory anemia without ring sideroblasts, so stated

      Inclusion term(s):

      • Refractory anemia without sideroblasts, without excess of blasts
    2. D46.1 Refractory anemia with ring sideroblasts

      Inclusion term(s):

      • RARS
    3. D46.2 Refractory anemia with excess of blasts [RAEB]

      1. D46.20 Refractory anemia with excess of blasts, unspecified

        Inclusion term(s):

        • RAEB NOS
      2. D46.21 Refractory anemia with excess of blasts 1

        Inclusion term(s):

        • RAEB 1
      3. D46.22 Refractory anemia with excess of blasts 2

        Inclusion term(s):

        • RAEB 2
    4. D46.4 Refractory anemia, unspecified

    5. D46.9 Myelodysplastic syndrome, unspecified

      Inclusion term(s):

      • Myelodysplasia NOS
    6. D46.A Refractory cytopenia with multilineage dysplasia

    7. D46.B Refractory cytopenia with multilineage dysplasia and ring sideroblasts

      Inclusion term(s):

      • RCMD RS
    8. D46.C Myelodysplastic syndrome with isolated del(5q) chromosomal abnormality

      Inclusion term(s):

      • Myelodysplastic syndrome with 5q deletion
      • 5q minus syndrome NOS
    9. D46.Z Other myelodysplastic syndromes

Abbreviations used here:

NEC Not elsewhere classifiable
This abbreviation in the Tabular List represents “other specified”. When a specific code is not available for a condition, the Tabular List includes an NEC entry under a code to identify the code as the “other specified” code.

NOS Not otherwise specified
This abbreviation is the equivalent of unspecified.