2027 ICD-10-CM Diagnosis Code C84Mature T/NK-cell lymphomas

ICD-10-CM Codes›C00–D49›C81-C96›C84

ICD-10-CM C84
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

C84 is a non-billable ICD-10-CM category code for mature T/NK-cell lymphomas, so it cannot be submitted on claims. Use a more specific code from this category instead, such as C84.00, C84.01, C84.02, and C84.03.

Code Identity

ICD-10-CM Code
C84
Billable Status
No — Non-Billable Category
Code Describes
Mature T/NK-cell lymphomas
Short Description
Mature T/NK-cell lymphomas
Same as the full description in the CMS dataset.
Chapter
C81-C96
Malignant neoplasms of lymphoid, hematopoietic and related tissue

Code Classification

ChapterC00–D49Neoplasms
SectionC81-C96Malignant neoplasms of lymphoid, hematopoietic and related tissue
CategoryC84Mature T/NK-cell lymphomas
This CodeC84Mature T/NK-cell lymphomas

Specific Coding for Mature T/NK-cell lymphomasOverview

Non-specific codes like C84 require more characters. Use one of these billable codes instead:

  • C84.0 for Mycosis fungoides

  • Use C84.00 for Mycosis fungoides, unspecified site

  • Use C84.01 for Mycosis fungoides, lymph nodes of head, face, and neck

  • Use C84.02 for Mycosis fungoides, intrathoracic lymph nodes

  • Use C84.03 for Mycosis fungoides, intra-abdominal lymph nodes

  • Use C84.04 for Mycosis fungoides, lymph nodes of axilla and upper limb

  • Use C84.05 for Mycosis fungoides, lymph nodes of inguinal region and lower limb

  • Use C84.06 for Mycosis fungoides, intrapelvic lymph nodes

  • Use C84.07 for Mycosis fungoides, spleen

  • Use C84.08 for Mycosis fungoides, lymph nodes of multiple sites

  • Use C84.09 for Mycosis fungoides, extranodal and solid organ sites

  • Use C84.0A for Mycosis fungoides, in remission

  • C84.1 for Sezary disease

  • Use C84.10 for Sezary disease, unspecified site

  • Use C84.11 for Sezary disease, lymph nodes of head, face, and neck

  • Use C84.12 for Sezary disease, intrathoracic lymph nodes

  • Use C84.13 for Sezary disease, intra-abdominal lymph nodes

  • Use C84.14 for Sezary disease, lymph nodes of axilla and upper limb

  • Use C84.15 for Sezary disease, lymph nodes of inguinal region and lower limb

  • Use C84.16 for Sezary disease, intrapelvic lymph nodes

  • Use C84.17 for Sezary disease, spleen

  • Use C84.18 for Sezary disease, lymph nodes of multiple sites

  • Use C84.19 for Sezary disease, extranodal and solid organ sites

  • Use C84.1A for Sezary disease, in remission

  • C84.4 for Peripheral T-cell lymphoma, not elsewhere classified

  • Use C84.40 for Peripheral T-cell lymphoma, not elsewhere classified, unspecified site

  • Use C84.41 for Peripheral T-cell lymphoma, not elsewhere classified, lymph nodes of head, face, and neck

  • Use C84.42 for Peripheral T-cell lymphoma, not elsewhere classified, intrathoracic lymph nodes

  • Use C84.43 for Peripheral T-cell lymphoma, not elsewhere classified, intra-abdominal lymph nodes

  • Use C84.44 for Peripheral T-cell lymphoma, not elsewhere classified, lymph nodes of axilla and upper limb

  • Use C84.45 for Peripheral T-cell lymphoma, not elsewhere classified, lymph nodes of inguinal region and lower limb

  • Use C84.46 for Peripheral T-cell lymphoma, not elsewhere classified, intrapelvic lymph nodes

  • Use C84.47 for Peripheral T-cell lymphoma, not elsewhere classified, spleen

  • Use C84.48 for Peripheral T-cell lymphoma, not elsewhere classified, lymph nodes of multiple sites

  • Use C84.49 for Peripheral T-cell lymphoma, not elsewhere classified, extranodal and solid organ sites

  • Use C84.4A for Peripheral T-cell lymphoma, not elsewhere classified, in remission

  • C84.6 for Anaplastic large cell lymphoma, ALK-positive

  • Use C84.60 for Anaplastic large cell lymphoma, ALK-positive, unspecified site

  • Use C84.61 for Anaplastic large cell lymphoma, ALK-positive, lymph nodes of head, face, and neck

  • Use C84.62 for Anaplastic large cell lymphoma, ALK-positive, intrathoracic lymph nodes

  • Use C84.63 for Anaplastic large cell lymphoma, ALK-positive, intra-abdominal lymph nodes

  • Use C84.64 for Anaplastic large cell lymphoma, ALK-positive, lymph nodes of axilla and upper limb

  • Use C84.65 for Anaplastic large cell lymphoma, ALK-positive, lymph nodes of inguinal region and lower limb

  • Use C84.66 for Anaplastic large cell lymphoma, ALK-positive, intrapelvic lymph nodes

  • Use C84.67 for Anaplastic large cell lymphoma, ALK-positive, spleen

  • Use C84.68 for Anaplastic large cell lymphoma, ALK-positive, lymph nodes of multiple sites

  • Use C84.69 for Anaplastic large cell lymphoma, ALK-positive, extranodal and solid organ sites

  • Use C84.6A for Anaplastic large cell lymphoma, ALK-positive, in remission

  • C84.7 for Anaplastic large cell lymphoma, ALK-negative

  • Use C84.70 for Anaplastic large cell lymphoma, ALK-negative, unspecified site

  • Use C84.71 for Anaplastic large cell lymphoma, ALK-negative, lymph nodes of head, face, and neck

  • Use C84.72 for Anaplastic large cell lymphoma, ALK-negative, intrathoracic lymph nodes

  • Use C84.73 for Anaplastic large cell lymphoma, ALK-negative, intra-abdominal lymph nodes

  • Use C84.74 for Anaplastic large cell lymphoma, ALK-negative, lymph nodes of axilla and upper limb

  • Use C84.75 for Anaplastic large cell lymphoma, ALK-negative, lymph nodes of inguinal region and lower limb

  • Use C84.76 for Anaplastic large cell lymphoma, ALK-negative, intrapelvic lymph nodes

  • Use C84.77 for Anaplastic large cell lymphoma, ALK-negative, spleen

  • Use C84.78 for Anaplastic large cell lymphoma, ALK-negative, lymph nodes of multiple sites

  • Use C84.79 for Anaplastic large cell lymphoma, ALK-negative, extranodal and solid organ sites

  • Use C84.7A for Anaplastic large cell lymphoma, ALK-negative, breast

  • Use C84.7B for Anaplastic large cell lymphoma, ALK-negative, in remission

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

  • Use C84.90 for Mature T/NK-cell lymphomas, unspecified, unspecified site

  • Use C84.91 for Mature T/NK-cell lymphomas, unspecified, lymph nodes of head, face, and neck

  • Use C84.92 for Mature T/NK-cell lymphomas, unspecified, intrathoracic lymph nodes

  • Use C84.93 for Mature T/NK-cell lymphomas, unspecified, intra-abdominal lymph nodes

  • Use C84.94 for Mature T/NK-cell lymphomas, unspecified, lymph nodes of axilla and upper limb

  • Use C84.95 for Mature T/NK-cell lymphomas, unspecified, lymph nodes of inguinal region and lower limb

  • Use C84.96 for Mature T/NK-cell lymphomas, unspecified, intrapelvic lymph nodes

  • Use C84.97 for Mature T/NK-cell lymphomas, unspecified, spleen

  • Use C84.98 for Mature T/NK-cell lymphomas, unspecified, lymph nodes of multiple sites

  • Use C84.99 for Mature T/NK-cell lymphomas, unspecified, extranodal and solid organ sites

  • Use C84.9A for Mature T/NK-cell lymphomas, unspecified, in remission

  • C84.A for Cutaneous T-cell lymphoma, unspecified

  • Use C84.A0 for Cutaneous T-cell lymphoma, unspecified, unspecified site

  • Use C84.A1 for Cutaneous T-cell lymphoma, unspecified lymph nodes of head, face, and neck

  • Use C84.A2 for Cutaneous T-cell lymphoma, unspecified, intrathoracic lymph nodes

  • Use C84.A3 for Cutaneous T-cell lymphoma, unspecified, intra-abdominal lymph nodes

  • Use C84.A4 for Cutaneous T-cell lymphoma, unspecified, lymph nodes of axilla and upper limb

  • Use C84.A5 for Cutaneous T-cell lymphoma, unspecified, lymph nodes of inguinal region and lower limb

  • Use C84.A6 for Cutaneous T-cell lymphoma, unspecified, intrapelvic lymph nodes

  • Use C84.A7 for Cutaneous T-cell lymphoma, unspecified, spleen

  • Use C84.A8 for Cutaneous T-cell lymphoma, unspecified, lymph nodes of multiple sites

  • Use C84.A9 for Cutaneous T-cell lymphoma, unspecified, extranodal and solid organ sites

  • Use C84.AA for Cutaneous T-cell lymphoma, unspecified, in remission

  • C84.Z for Other mature T/NK-cell lymphomas

  • Use C84.Z0 for Other mature T/NK-cell lymphomas, unspecified site

  • Use C84.Z1 for Other mature T/NK-cell lymphomas, lymph nodes of head, face, and neck

  • Use C84.Z2 for Other mature T/NK-cell lymphomas, intrathoracic lymph nodes

  • Use C84.Z3 for Other mature T/NK-cell lymphomas, intra-abdominal lymph nodes

  • Use C84.Z4 for Other mature T/NK-cell lymphomas, lymph nodes of axilla and upper limb

  • Use C84.Z5 for Other mature T/NK-cell lymphomas, lymph nodes of inguinal region and lower limb

  • Use C84.Z6 for Other mature T/NK-cell lymphomas, intrapelvic lymph nodes

  • Use C84.Z7 for Other mature T/NK-cell lymphomas, spleen

  • Use C84.Z8 for Other mature T/NK-cell lymphomas, lymph nodes of multiple sites

  • Use C84.Z9 for Other mature T/NK-cell lymphomas, extranodal and solid organ sites

  • Use C84.ZA for Other mature T/NK-cell lymphomas, in remission

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to C84: its own notes plus those printed at block C81-C96 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.

  • personal history of non-Hodgkin lymphoma (Z85.72)

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.

From Block C81-C96 Malignant neoplasms of lymphoid, hematopoietic and related tissue applies to 533 codes
  • 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)

Notes

General instructions on how these codes are used.

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 C84, its category, or a range that includes it.

Excludes1 4

These codes carry an Excludes1 note naming C84: they are not reported together with it, unless the two conditions are unrelated.

  • C82 Follicular lymphoma
    mature T/NK-cell lymphomas (C84.-)
  • C83.0 Small cell B-cell lymphoma
    mature T/NK-cell lymphomas (C84.-)
  • C83.3 Diffuse large B-cell lymphoma
    mature T/NK-cell lymphomas (C84.-)
  • C86 Other specified types of T/NK-cell lymphoma
    mature T/NK-cell lymphomas (C84.-)

Patient EducationClinical

Lymphoma

Lymphoma is a cancer of a part of the immune system called the lymph system. There are many types of lymphoma. One type is Hodgkin disease. The rest are called non-Hodgkin lymphomas.

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 C84Overview

What is the ICD-10 code for mature T/NK-cell lymphomas?

C84 is the ICD-10-CM category for mature T/NK-cell lymphomas, but it is a non-billable header: claims need a more specific code from this category, listed on this page.

Is C84 (Mature T/NK-cell lymphomas) a billable code?

No. This is a category header that groups the codes for mature T/NK-cell lymphomas, and headers cannot be submitted on claims. Claims for mature T/NK-cell lymphomas need a more specific code from this category, such as C84.00, C84.01, and C84.02.

Can C84 be reported with Z85.72?

Not as a rule. The Excludes1 note on C84 lists "personal history of non-Hodgkin lymphoma (Z85.72)". 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).