2027 ICD-10-CM Diagnosis Code D46Myelodysplastic syndromes

ICD-10-CM Codes›C00–D49›D37-D48›D46

ICD-10-CM D46
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

D46 is a non-billable ICD-10-CM category code for myelodysplastic syndromes, so it cannot be submitted on claims. Use a more specific code from this category instead, such as D46.0, D46.1, D46.20, and D46.21.

Code Identity

ICD-10-CM Code
D46
Billable Status
No — Non-Billable Category
Code Describes
Myelodysplastic syndromes
Short Description
Myelodysplastic syndromes
Same as the full description in the CMS dataset.
Chapter
D37-D48
Neoplasms of uncertain behavior, polycythemia vera and myelodysplastic syndromes

Code Classification

ChapterC00–D49Neoplasms
SectionD37-D48Neoplasms of uncertain behavior, polycythemia vera and myelodysplastic syndromes
CategoryD46Myelodysplastic syndromes
This CodeD46Myelodysplastic syndromes

Specific Coding for Myelodysplastic syndromesOverview

Non-specific codes like D46 require more characters. Use one of these billable codes instead:

  • Use D46.0 for Refractory anemia without ring sideroblasts, so stated

  • Use D46.1 for Refractory anemia with ring sideroblasts

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

  • Use D46.20 for Refractory anemia with excess of blasts, unspecified

  • Use D46.21 for Refractory anemia with excess of blasts 1

  • Use D46.22 for Refractory anemia with excess of blasts 2

  • Use D46.4 for Refractory anemia, unspecified

  • Use D46.9 for Myelodysplastic syndrome, unspecified

  • Use D46.A for Refractory cytopenia with multilineage dysplasia

  • Use D46.B for Refractory cytopenia with multilineage dysplasia and ring sideroblasts

  • Use D46.C for Myelodysplastic syndrome with isolated del(5q) chromosomal abnormality

  • Use D46.Z for Other myelodysplastic syndromes

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to D46: its own notes plus those printed at block D37-D48 and Chapter 2. A note printed at a category, block or chapter applies to every code under it.

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From Block D37-D48 Neoplasms of uncertain behavior, polycythemia vera and myelodysplastic syndromes applies to 137 codes
  • neoplasms of unspecified behavior (D49.-)

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

  • drug-induced aplastic anemia (D61.1)

Use Additional Code

Add a second code, after this one, to fully describe the condition.

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

Notes

General instructions on how these codes are used.

From Block D37-D48 Neoplasms of uncertain behavior, polycythemia vera and myelodysplastic syndromes applies to 137 codes
  • 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.
From Chapter 2 (C00-D49) Neoplasms applies to 1,730 codes
  • Functional activity
  • All neoplasms are classified in this chapter, whether they are functionally active or not. An additional code from Chapter 4 may be used, to identify functional activity associated with any neoplasm.
  • Morphology [Histology]
  • Chapter 2 classifies neoplasms primarily by site (topography), with broad groupings for behavior, malignant, in situ, benign, etc. The Table of Neoplasms should be used to identify the correct topography code. In a few cases, such as for malignant melanoma and certain neuroendocrine tumors, the morphology (histologic type) is included in the category and codes.
  • Primary malignant neoplasms overlapping site boundaries
  • A primary malignant neoplasm that overlaps two or more contiguous (next to each other) sites should be classified to the subcategory/code .8 ('overlapping lesion'), unless the combination is specifically indexed elsewhere. For multiple neoplasms of the same site that are not contiguous, such as tumors in different quadrants of the same breast, codes for each site should be assigned.
  • Malignant neoplasm of ectopic tissue
  • Malignant neoplasms of ectopic tissue are to be coded to the site mentioned, e.g., ectopic pancreatic malignant neoplasms are coded to pancreas, unspecified (C25.9).

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name D46, its category, or a range that includes it.

Excludes1 2

These codes carry an Excludes1 note naming D46: they are not reported together with it, unless the two conditions are unrelated.

  • C94 Other leukemias of specified cell type
    myelodysplastic syndromes (D46.-)
  • D64 Other anemias
    refractory anemia (D46.-)

Excludes2 1

These codes carry an Excludes2 note naming D46: its condition is not part of those codes, and both may be reported when the patient has both.

  • D61.81 Pancytopenia
    pancytopenia (due to) (with) myelodysplastic syndromes (D46.-)

Use Additional Code 1

These codes say to use an additional code from the note, and D46 is one of the codes named.

  • D75.81 Myelofibrosis
    code, if applicable, for associated therapy-related myelodysplastic syndrome (D46.-)

Code Also 1

These codes say D46 may also be needed to fully describe the condition. The note gives no sequencing direction.

  • D61.02 Shwachman-Diamond syndrome
    myelodysplastic syndrome (D46.-)

Clinical InformationClinical

  • Myelodysplastic Syndromes

    clonal hematopoietic stem cell disorders characterized by dysplasia in one or more hematopoietic cell lineages. they predominantly affect patients over 60, are considered preleukemic conditions, and have high probability of transformation into acute myeloid leukemia.

Patient EducationClinical

Myelodysplastic Syndromes

Your bone marrow is the spongy tissue inside some of your bones, such as your hip and thigh bones. It contains immature cells, called stem cells. The stem cells can develop into the red blood cells that carry oxygen through your body, the white blood cells that fight infections, and the platelets that help with blood clotting.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About D46Overview

What is the ICD-10 code for myelodysplastic syndromes?

D46 is the ICD-10-CM category for myelodysplastic syndromes, but it is a non-billable header: claims need a more specific code from this category, listed on this page.

Is D46 (Myelodysplastic syndromes) a billable code?

No. This is a category header that groups the codes for myelodysplastic syndromes, and headers cannot be submitted on claims. Claims for myelodysplastic syndromes need a more specific code from this category, such as D46.0, D46.1, and D46.20.

Can D46 be reported with a code from D49?

Not as a rule. The Excludes1 note at block D37-D48, which applies to D46, lists "neoplasms of unspecified behavior (D49.-)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).

Does D46 need an additional code?

When the condition applies, yes. The Use Additional Code note reads: code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5). The additional code is reported after D46.