ICD10
ICD-10 Code C84.4: Peripheral T-cell lymphoma, not elsewhere classified
Reviewed by HealthAssure Clinical TeamUpdated 26 May 2026
What is this code?
ICD-10 entries help standardize how diagnoses are organized for coding, reporting, analytics, and documentation. This code sits within the broader ICD-10 area for Neoplasms (C00-D49).
When is it used?
- May be used when a clinician documents peripheral t-cell lymphoma, not elsewhere classified in a patient's medical record.
- May appear in hospital records, claims, referrals, and clinical documentation.
- This code may act more like a grouping or parent code, so a more specific child code may be used in final documentation when available.
What it does not mean
- A code alone does not explain severity, treatment plan, or outcome.
- A medical code should not be treated as a substitute for a doctor's diagnosis or advice.
- This entry may represent a broader category rather than the most specific billable code.
Code hierarchy
chapter
2Neoplasms (C00-D49)
block
C00-C96Malignant neoplasms
block
C81-C96Malignant neoplasms of lymphoid, hematopoietic and related tissue
category
C84Mature T/NK-cell lymphomas
currentC84
Official coding notes
Inclusion terms
- Lennert's lymphoma
- Lymphoepithelioid lymphoma
- Mature T-cell lymphoma, not elsewhere classified
Where you may see this code
You may see this entry in coding references, medical records, or claims workflows when a broader diagnosis category is being reviewed before a more specific code is chosen.
Related specialists
OncologistGeneral Physician
Related codes
C84.40Peripheral T-cell lymphoma, not elsewhere classified, unspecified sitecodeC84.41Peripheral T-cell lymphoma, not elsewhere classified, lymph nodes of head, face, and neckcodeC84.42Peripheral T-cell lymphoma, not elsewhere classified, intrathoracic lymph nodescodeC84.43Peripheral T-cell lymphoma, not elsewhere classified, intra-abdominal lymph nodescodeC84.44Peripheral T-cell lymphoma, not elsewhere classified, lymph nodes of axilla and upper limbcodeC84.45Peripheral T-cell lymphoma, not elsewhere classified, lymph nodes of inguinal region and lower limbcodeC84.46Peripheral T-cell lymphoma, not elsewhere classified, intrapelvic lymph nodescodeC84.47Peripheral T-cell lymphoma, not elsewhere classified, spleencodeC84.48Peripheral T-cell lymphoma, not elsewhere classified, lymph nodes of multiple sitescodeC84.49Peripheral T-cell lymphoma, not elsewhere classified, extranodal and solid organ sitescodeC84.4APeripheral T-cell lymphoma, not elsewhere classified, in remissioncode
Sibling codes
Mapped diagnoses and classifications
SNOMED_CT 404134006high
Anaplastic large T-cell systemic malignant lymphoma
Source: SNOMED International ICD-10 map
SNOMED_CT 703626001high
Anaplastic large cell lymphoma, T/Null cell, primary systemic type
Source: SNOMED International ICD-10 map
SNOMED_CT 404129007high
CD-30 negative anaplastic large T-cell cutaneous lymphoma
Source: SNOMED International ICD-10 map
SNOMED_CT 277613000high
Cutaneous peripheral T-cell lymphoma
Source: SNOMED International ICD-10 map
SNOMED_CT 277643003high
High grade T-cell lymphoma
Source: SNOMED International ICD-10 map
SNOMED_CT 702785000high
Large cell anaplastic lymphoma T cell and null cell type
Source: SNOMED International ICD-10 map
Coding guidelines
Compatibility
Legacy code aligns to an official FY 2026 category. Frontend should resolve to the official category page and surface the billable child codes.
Legacy codes
C84.4
Replacement codes
C84.40 — Peripheral T-cell lymphoma, not elsewhere classified, unspecified siteC84.41 — Peripheral T-cell lymphoma, not elsewhere classified, lymph nodes of head, face, and neckC84.42 — Peripheral T-cell lymphoma, not elsewhere classified, intrathoracic lymph nodesC84.43 — Peripheral T-cell lymphoma, not elsewhere classified, intra-abdominal lymph nodesC84.44 — Peripheral T-cell lymphoma, not elsewhere classified, lymph nodes of axilla and upper limbC84.45 — Peripheral T-cell lymphoma, not elsewhere classified, lymph nodes of inguinal region and lower limbC84.46 — Peripheral T-cell lymphoma, not elsewhere classified, intrapelvic lymph nodesC84.47 — Peripheral T-cell lymphoma, not elsewhere classified, spleenC84.48 — Peripheral T-cell lymphoma, not elsewhere classified, lymph nodes of multiple sitesC84.49 — Peripheral T-cell lymphoma, not elsewhere classified, extranodal and solid organ sitesC84.4A — Peripheral T-cell lymphoma, not elsewhere classified, in remission
Common synonyms
Peripheral T-cell lymphoma, not elsewhere classified
Frequently asked questions
About this content
This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.