ICD-10-CM 2027 diagnosis code

C93Monocytic leukemia

Not billable — use a more specific code

C93 is a header code, so it can't be reported by itself. Choose one of the 5 more specific codes beneath it.

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About C93

C93 is the ICD-10-CM diagnosis code for monocytic leukemia. It belongs to block C81-C96 (malignant neoplasms of lymphoid, hematopoietic and related tissue) and chapter 2 (neoplasms). It is a header code, so it can't be reported by itself; one of its 5 subcodes must be used instead.

To report this condition, pick the subcode that matches the documentation: C93.0 (leukemia), C93.1 (leukemia), C93.3 (leukemia), C93.9 (unspecified) and C93.Z (leukemia).

Don't report C93 together with the conditions in its Excludes1 note: personal history of leukemia (Z85.6).

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Specific codes under C93

Coding notes

IncludesFurther defines the content of the category

monocytoid leukemia

Excludes1Not coded here — never report together with this code

personal history of leukemia (Z85.6)

Notes that apply from higher levels

Instructions written at a parent level also apply to C93.

Broader instructions also apply from C81-C96 Malignant neoplasms of lymphoid, hematopoietic and related tissue and Chapter 2: Neoplasms.

Codes whose notes reference C93

D72.825Excludes1

Code history

2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027

FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
No changes since FY2016.

Common questions about C93

Is C93 billable?: No. C93 is a header code. Report one of its more specific subcodes instead.