C84.40

Billable

Peripheral T-cell lymphoma, not elsewhere classified, unspecified site

HCC Category Mapping

V28HCC 19 — Lymphoma and Other Cancers

0.105

V24HCC 10 — Lymphoma and Other Cancers

0.675

ESRDHCC 10 — Lymphoma and Other Cancers

0.000

RxHCCHCC 21 — Hodgkin Lymphoma and Other Cancers

0.000

What This Code Means

A type of T-cell lymphoma (a blood cancer) that does not fit into other specific categories and affects an unspecified location in the body.

Coding Tips

•Use this code only when the specific site of involvement is not documented or is unknown
•If a specific lymph node site is documented, use codes C84.41-C84.46 instead

Clinical Significance

Peripheral T-cell lymphoma, not elsewhere classified, at an unspecified site is an aggressive non-Hodgkin lymphoma originating from mature T-cells that does not fit into other specific T-cell lymphoma categories. This is a heterogeneous group of lymphomas with generally poor prognosis and limited treatment options compared to B-cell lymphomas. Accurate identification is important because peripheral T-cell lymphomas require different treatment protocols than B-cell lymphomas.

Documentation Requirements

✓Pathology confirming peripheral T-cell lymphoma with immunohistochemistry demonstrating T-cell markers
✓Exclusion of other specific T-cell lymphoma subtypes (mycosis fungoides, Sezary disease, anaplastic large cell lymphoma, etc.)
✓Staging documentation including imaging (CT or PET/CT)
✓Documentation of specific site if available — query provider if site not specified
✓Treatment plan — typically anthracycline-based chemotherapy

Commonly Confused Codes

C84.00 — Mycosis fungoides: A cutaneous T-cell lymphoma with distinct biology and treatment; peripheral T-cell lymphoma is a nodal/systemic disease C84.10 — Sezary disease: A leukemic cutaneous T-cell lymphoma, distinct from peripheral T-cell lymphoma C86.0-C86.6 — Other specified T-cell lymphomas: Specific entities like hepatosplenic T-cell lymphoma, subcutaneous panniculitis-like T-cell lymphoma have their own codes C85.10 — Unspecified B-cell lymphoma: Verify T-cell vs. B-cell lineage on immunohistochemistry; treatment is fundamentally different

Code Hierarchy

└C84Mature T/NK-cell lymphomas └C84.4Peripheral T-cell lymphoma, not elsewhere classified └C84.40Peripheral T-cell lymphoma, not elsewhere classified, unspecified site

└C84.40Peripheral T-cell lymphoma, not elsewhere classified, unspecified site