2026 ICD-10-CM Diagnosis Code C86.40Blastic NK-cell lymphoma not having achieved remission

ICD-10-CM Codes›C00–D49›C81-C96›C86

ICD-10-CM C86.40
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

C86.40 is a billable ICD-10-CM diagnosis code for blastic NK-cell lymphoma not having achieved 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. Coders also document this condition as blastic plasmacytoid dendritic cell neoplasm. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Non-Hodgkin lymphoma.

Code Identity

ICD-10-CM Code
C86.40
Billable Status
Yes — Valid for Submission
Code Describes
Blastic NK-cell lymphoma not having achieved remission
Short Description
Blastic NK-cell lymphoma not having achieved remission
Same as the full description in the CMS dataset.
Parent Code
C86.4
Blastic NK-cell lymphoma

Code Classification

ChapterC00–D49Neoplasms
SectionC81-C96Malignant neoplasms of lymphoid, hematopoietic and related tissue
CategoryC86Other specified types of T/NK-cell lymphoma
This CodeC86.40Blastic NK-cell lymphoma not having achieved remission

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Blastic plasmacytoid dendritic cell neoplasm
  • NK-lymphoblastic leukemia/lymphoma

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Blastic NK-cell lymphoma NOS
  • Blastic NK-cell lymphoma with failed remission
  • Blastic plasmacytoid dendritic cell neoplasm (BPDCN) NOS
  • Blastic plasmacytoid dendritic cell neoplasm (BPDCN) not having achieved remission
  • Blastic plasmacytoid dendritic cell neoplasm (BPDCN) with failed remission

Clinical ClassificationClinical

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

CCSR NEO058
Non-Hodgkin lymphoma
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Blastic Plasmacytoid Dendritic Cell Neoplasm

    a rare and aggressive hematologic malignancy derived from the precursors of plasmacytoid dendritic cells. blastic plasmacytoid dendritic cell neoplasms affect bone marrow and blood in addition to the lymph nodes, spleen, central nervous system, and skin.

Code History & ChangesHistory

Replacement C86.40 replaces the following previously assigned code(s):

  • C86.4 - Blastic NK-cell lymphoma
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 C86.40Overview

Is C86.40 (Blastic NK-cell lymphoma) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report blastic NK-cell lymphoma not having achieved remission on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does C86.40 group to?

When blastic NK-cell lymphoma not having achieved 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.