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This neoplasm is not reportable.
Name
Clonal cytopenia of undetermined significance (CCUS)
ICD-O-3 Morphology
9980/1
Effective
2026 and later
Reportability
This neoplasm is not reportable
Primary Site(s)
C421
Primary site bone marrow (C421)
This hematopoietic disease is not reportable for the U.S.
Canada, refer to your specific province for reportability requirements.
This hematopoietic disease is not reportable for the U.S.
Canada, refer to your specific province for reportability requirements.
Abstractor Notes
Clonal cytopenia of undetermined significance (CCUS) is part of the Myeloid precursor lesions lineage table in the WHO 5th edition of Hematolymphoid Tumors. (See Appendix B in the Hematopoietic Manual, Table B1)
Bone marrow examination is needed to rule other causes of cytopenia, including other myeloid neoplasms.
Progression to a myeloid neoplasm, particularly MDS, increases with the size of the clonal population.
- If a patient with history of CCUS progresses to MDS, the MDS is the first primary
Bone marrow examination is needed to rule other causes of cytopenia, including other myeloid neoplasms.
Progression to a myeloid neoplasm, particularly MDS, increases with the size of the clonal population.
- If a patient with history of CCUS progresses to MDS, the MDS is the first primary
Alternate Names
Idiopathic cytopenia of unknown significance (ICUS)
Definition
Sources
WHO Classification of Tumours Editorial Board. Haematolymphoid tumours. Lyon (France): International Agency for Research on Cancer; 2024. (WHO classification of tumours series, 5th ed.; vol. 11). https://publications.iarc.who.int/637.
Section: Myeloid precursor lesions
Pages: Part A: 24-25
Section: Myeloid precursor lesions
Pages: Part A: 24-25
