C91.5

Non-Billable
ChapterC00–D49
Ranksubcategory
Official Description

Adult T-cell lymphoma/leukemia (HTLV-1-associated)

Metadata & Insights
  • 2026 ICD-10-CM Edition - Effective October 1, 2025.
  • Non-billable category (requires more specific sub-code).
  • Chapter 2: Neoplasms (C00-D49).

Instructional Notes

Includes
  • Acute variant of adult T-cell lymphoma/leukemia (HTLV-1-associated)
  • Chronic variant of adult T-cell lymphoma/leukemia (HTLV-1-associated)
  • Lymphomatoid variant of adult T-cell lymphoma/leukemia (HTLV-1-associated)
  • Smouldering variant of adult T-cell lymphoma/leukemia (HTLV-1-associated)
General instructions are available for the parent sections:

Clinical Hierarchy

CH2Neoplasms (C00-D49)
C81-C96Malignant neoplasms of lymphoid, hematopoietic and related tissue (C81-C96)
C91Lymphoid leukemia
C91.5Adult T-cell lymphoma/leukemia (HTLV-1-associated)
C91.50Adult T-cell lymphoma/leukemia (HTLV-1-associated) not having achieved remission
C91.51Adult T-cell lymphoma/leukemia (HTLV-1-associated), in remission
C91.52Adult T-cell lymphoma/leukemia (HTLV-1-associated), in relapse

Applicable Ancestor Context

The following parent sections contain instructions or notes that apply to C91.5:

categoryC91
Lymphoid leukemia
View context instructions
blockC81-C96
Malignant neoplasms of lymphoid, hematopoietic and related tissue (C81-C96)
View context instructions

Alphabetic Index Mentions

These are Diagnosis Index lookup paths that route to C91.5. Use them as entry terms for search, then confirm final coding instructions in the Tabular List and notes above.

2 raw paths

MS-DRG Classification

2026

No direct MS-DRG triggers identified.

Cross Reference

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Find surgical and procedural codes related to Adult T-cell lymphoma/leukemia (HTLV-1-associated).

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