2023 ICD-10-CM Diagnosis Code C96.21

Aggressive systemic mastocytosis

    2018 - New Code 2019 2020 2021 2022 2023 Billable/Specific Code
  • C96.21 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
  • The 2023 edition of ICD-10-CM C96.21 became effective on October 1, 2022.
  • This is the American ICD-10-CM version of C96.21 - other international versions of ICD-10 C96.21 may differ.
The following code(s) above C96.21 contain annotation back-references
Annotation Back-References
In this context, annotation back-references refer to codes that contain:
  • Applicable To annotations, or
  • Code Also annotations, or
  • Code First annotations, or
  • Excludes1 annotations, or
  • Excludes2 annotations, or
  • Includes annotations, or
  • Note annotations, or
  • Use Additional annotations
that may be applicable to C96.21:
  • C00-D49
    2023 ICD-10-CM Range C00-D49

    Neoplasms

    Note
    • 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).
    Neoplasms
  • C81-C96
    2023 ICD-10-CM Range C81-C96

    Malignant neoplasms of lymphoid, hematopoietic and related tissue

    Type 2 Excludes
    • Kaposi's sarcoma of lymph nodes (C46.3)
    • secondary and unspecified neoplasm of lymph nodes (C77.-)
    • secondary neoplasm of bone marrow (C79.52)
    • secondary neoplasm of spleen (C78.89)
    Malignant neoplasms of lymphoid, hematopoietic and related tissue
  • C96
    ICD-10-CM Diagnosis Code C96

    Other and unspecified malignant neoplasms of lymphoid, hematopoietic and related tissue

      2016 2017 2018 2019 2020 2021 2022 2023 Non-Billable/Non-Specific Code
    Type 1 Excludes
    • personal history of other malignant neoplasms of lymphoid, hematopoietic and related tissues (Z85.79)
    Other and unspecified malignant neoplasms of lymphoid, hematopoietic and related tissue
  • C96.2
    ICD-10-CM Diagnosis Code C96.2

    Malignant mast cell neoplasm

      2016 2017 2018 - Converted to Parent Code 2019 2020 2021 2022 2023 Non-Billable/Non-Specific Code
    Type 1 Excludes
    • indolent mastocytosis (D47.02)
    • mast cell leukemia (C94.30)
    • mastocytosis (congenital) (cutaneous) (Q82.2)
    Malignant mast cell neoplasm
ICD-10-CM C96.21 is grouped within Diagnostic Related Group(s) (MS-DRG v40.0):
  • 011 Tracheostomy for face, mouth and neck diagnoses or laryngectomy with mcc
  • 012 Tracheostomy for face, mouth and neck diagnoses or laryngectomy with cc
  • 013 Tracheostomy for face, mouth and neck diagnoses or laryngectomy without cc/mcc
  • 820 Lymphoma and leukemia with major o.r. Procedures with mcc
  • 821 Lymphoma and leukemia with major o.r. Procedures with cc
  • 822 Lymphoma and leukemia with major o.r. Procedures without cc/mcc
  • 823 Lymphoma and non-acute leukemia with other procedures with mcc
  • 824 Lymphoma and non-acute leukemia with other procedures with cc
  • 825 Lymphoma and non-acute leukemia with other procedures without cc/mcc
  • 840 Lymphoma and non-acute leukemia with mcc
  • 841 Lymphoma and non-acute leukemia with cc
  • 842 Lymphoma and non-acute leukemia without cc/mcc

Convert C96.21 to ICD-9-CM

Code History
  • 2018 (effective 10/1/2017): New code
  • 2019 (effective 10/1/2018): No change
  • 2020 (effective 10/1/2019): No change
  • 2021 (effective 10/1/2020): No change
  • 2022 (effective 10/1/2021): No change
  • 2023 (effective 10/1/2022): No change
Code annotations containing back-references to C96.21:
  • Type 1 Excludes: D47.02
    , D89.4
    ICD-10-CM Diagnosis Code D47.02

    Systemic mastocytosis

      2018 - New Code 2019 2020 2021 2022 2023 Billable/Specific Code
    Applicable To
    • Indolent systemic mastocytosis
    • Isolated bone marrow mastocytosis
    • Smoldering systemic mastocytosis
    • Systemic mastocytosis, with an associated hematological non-mast cell lineage disease (SM-AHNMD)
    Code Also
    • , if applicable, any associated hematological non-mast cell lineage disease, such as:
    • acute myeloid leukemia (C92.6-, C92.A-)
    • chronic myelomonocytic leukemia (C93.1-)
    • essential thrombocytosis (D47.3)
    • hypereosinophilic syndrome (D72.1)
    • myelodysplastic syndrome (D46.9)
    • myeloproliferative syndrome (D47.1)
    • non-Hodgkin lymphoma (C82-C85)
    • plasma cell myeloma (C90.0-)
    • polycythemia vera (D45)
    Type 1 Excludes
    • aggressive systemic mastocytosis (C96.21)
    • mast cell leukemia (C94.3-)
    ICD-10-CM Diagnosis Code D89.4

    Mast cell activation syndrome and related disorders

      2017 - New Code 2018 2019 2020 2021 2022 2023 Non-Billable/Non-Specific Code
    Type 1 Excludes
    • aggressive systemic mastocytosis (C96.21)
    • congenital cutaneous mastocytosis (Q82.2)
    • (non-congenital) cutaneous mastocytosis (D47.01)
    • (indolent) systemic mastocytosis (D47.02)
    • malignant mast cell neoplasm (C96.2-)
    • malignant mastocytoma (C96.29)
    • mast cell leukemia (C94.3-)
    • mast cell sarcoma (C96.22)
    • mastocytoma NOS (D47.09)
    • other mast cell neoplasms of uncertain behavior (D47.09)
    • systemic mastocytosis associated with a clonal hematologic non-mast cell lineage disease (SM-AHNMD) (D47.02)

Diagnosis Index entries containing back-references to C96.21:
  • Mastocytosis D47.09
    ICD-10-CM Diagnosis Code D47.09

    Other mast cell neoplasms of uncertain behavior

      2018 - New Code 2019 2020 2021 2022 2023 Billable/Specific Code
    Applicable To
    • Extracutaneous mastocytoma
    • Mast cell tumor NOS
    • Mastocytoma NOS
    • Mastocytosis NOS
    • aggressive systemic C96.21

ICD-10-CM Codes Adjacent To C96.21
C95.11 …… in remission
C95.12 …… in relapse
C95.9 Leukemia, unspecified
C95.90 …… not having achieved remission
C95.91 …… in remission
C95.92 …… in relapse
C96 Other and unspecified malignant neoplasms of lymphoid, hematopoietic and related tissue
C96.0 Multifocal and multisystemic (disseminated) Langerhans-cell histiocytosis
C96.2 Malignant mast cell neoplasm
C96.20 …… unspecified
C96.21 Aggressive systemic mastocytosis
C96.22 Mast cell sarcoma
C96.29 Other malignant mast cell neoplasm
C96.4 Sarcoma of dendritic cells (accessory cells)
C96.5 Multifocal and unisystemic Langerhans-cell histiocytosis
C96.6 Unifocal Langerhans-cell histiocytosis
C96.A Histiocytic sarcoma
C96.Z Other specified malignant neoplasms of lymphoid, hematopoietic and related tissue
C96.9 Malignant neoplasm of lymphoid, hematopoietic and related tissue, unspecified
D00 Carcinoma in situ of oral cavity, esophagus and stomach
D00.0 Carcinoma in situ of lip, oral cavity and pharynx

Reimbursement claims with a date of service on or after October 1, 2015 require the use of ICD-10-CM codes.