C84.9 Mature T/NK-cell lymphomas, unspecified

⚠ Non-Billable ICD-10-CM 2026
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The ICD-10-CM code for Mature T/NK-cell lymphomas, unspecified is C84.9 (FY2026). It is a non-billable category code — select a more specific code below for claims.

Classification

Section
C81-C96: Malignant neoplasms of lymphoid, hematopoietic and related tissue (C81-C96)
Category C84
98 codes (89 billable)
FY2026 Status
Stable since FY2024

Also Known As

ICD-10-CM Alphabetic Index entries that lead to C84.9:

  • Lymphoma (of) (malignant) › mature T/NK-cell
  • Lymphoma (of) (malignant) › NK/T cell
Excludes1
Not coded here. These conditions should NOT be coded together with C84.9.
  • mature T-cell lymphoma, not elsewhere classified (C84.4-)

Inclusion Terms

  • NK/T cell lymphoma NOS

Official Coding Guidelines

Tx of primary site (TOC entry)

a. Admission/Encounter for treatment of primary site ............................................................. 33

— ICD-10-CM Official Guidelines for Coding and Reporting, FY2026, Section I.C.2.a
Tx of secondary site (TOC entry)

b. Admission/Encounter for treatment of secondary site .......................................................... 33

— ICD-10-CM Official Guidelines for Coding and Reporting, FY2026, Section I.C.2.b

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

Cite This Page

Reference C84.9 with the canonical source and edition:

C84.9 — Mature T/NK-cell lymphomas, unspecified. ICD-10 Coding Pro (ICD-10-CM FY2026). https://icd10codingpro.com/codes/C84.9

Canonical URL: https://icd10codingpro.com/codes/C84.9

Related Codes

Parent Code

C84 Mature T/NK-cell lymphomas

More Specific Codes

C84.90 Mature T/NK-cell lymphomas, unspecified, unspecified site C84.91 Mature T/NK-cell lymphomas, unspecified, lymph nodes of head, face, and neck C84.92 Mature T/NK-cell lymphomas, unspecified, intrathoracic lymph nodes C84.93 Mature T/NK-cell lymphomas, unspecified, intra-abdominal lymph nodes C84.94 Mature T/NK-cell lymphomas, unspecified, lymph nodes of axilla and upper limb C84.95 Mature T/NK-cell lymphomas, unspecified, lymph nodes of inguinal region and lower limb C84.96 Mature T/NK-cell lymphomas, unspecified, intrapelvic lymph nodes C84.97 Mature T/NK-cell lymphomas, unspecified, spleen C84.98 Mature T/NK-cell lymphomas, unspecified, lymph nodes of multiple sites C84.99 Mature T/NK-cell lymphomas, unspecified, extranodal and solid organ sites C84.9A Mature T/NK-cell lymphomas, unspecified, in remission

Other Codes Under C84

C84.0 Mycosis fungoides C84.1 Sézary disease C84.4 Peripheral T-cell lymphoma, not elsewhere classified C84.6 Anaplastic large cell lymphoma, ALK-positive C84.7 Anaplastic large cell lymphoma, ALK-negative C84.A Cutaneous T-cell lymphoma, unspecified C84.Z Other mature T/NK-cell lymphomas
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Reviewed by Prajwal Shrestha, CPC, CRC
Certified Professional Coder (CPC) and Certified Risk Adjustment Coder (CRC) · AAPC Member ID 01997614 · About · Editorial policy · Content last reviewed: 2025-10-01

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