2026 ICD-10-CM Diagnosis Code C84.9AMature T/NK-cell lymphomas, unspecified, in remission

ICD-10-CM Codes›C00–D49›C81-C96›C84

ICD-10-CM C84.9A
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

C84.9A is a billable ICD-10-CM diagnosis code for mature T/NK-cell lymphomas, unspecified, in remission. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 820 through 825, 840 through 842, 974 through 976. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Non-Hodgkin lymphoma in remission.

Code Identity

ICD-10-CM Code
C84.9A
Billable Status
Yes — Valid for Submission
Code Describes
Mature T/NK-cell lymphomas, unspecified, in remission
Short Description
Mature T/NK-cell lymphomas, unspecified, in remission
Same as the full description in the CMS dataset.
Parent Code
C84.9
Mature T/NK-cell lymphomas, unspecified

Code Classification

ChapterC00–D49Neoplasms
SectionC81-C96Malignant neoplasms of lymphoid, hematopoietic and related tissue
CategoryC84Mature T/NK-cell lymphomas
This CodeC84.9AMature T/NK-cell lymphomas, unspecified, in remission

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR NEO077
Non-Hodgkin lymphoma in remission
Default principal diagnosis: inpatient Yes · outpatient Yes

Code History & ChangesHistory

Replacement C84.9A replaces the following previously assigned code(s):

  • Z85.72 - Personal history of non-Hodgkin lymphomas
FY 2025AddedAdded to the ICD-10-CM code setEffective October 1, 2024.
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About C84.9AOverview

Is C84.9A (Mature T/NK-cell lymphomas, unspecified) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report mature T/NK-cell lymphomas, unspecified, in remission on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does C84.9A group to?

When mature T/NK-cell lymphomas, unspecified, in remission is the principal diagnosis on an inpatient stay, it groups to MS-DRG 820, 821, 822, 823, 824, 825, 840, 841, 842, 974, 975, 976, with relative weights from 0.8945 to 5.8648 depending on complications. Higher weights mean higher Medicare reimbursement.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.