ICD-10 Code C84.Z8 – Other mature T/NK-cell lymphomas, lymph nodes of multiple sites (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C84.Z8 – Other mature T/NK-cell lymphomas, lymph nodes of multiple sites
What it is
This code identifies a mature T-cell or natural killer-cell lymphoma involving lymph nodes at multiple sites. Use it when the record specifies this lymphoma type and nodal distribution, but not a more specific subtype.
Clinical signs
Findings often include persistent enlarged lymph nodes in more than one region, sometimes with systemic “B” symptoms such as fever, night sweats, or weight loss. Clinical features vary; refer to documentation.
When to use this code
Use C84.Z8 when the provider documents other mature T/NK-cell lymphoma affecting lymph nodes of multiple sites and does not name a more specific codeable subtype. It may also apply when pathology or oncology notes confirm this diagnosis across multiple nodal regions. Check documentation if the anatomic sites are unclear.
Do not use for
Do not use this code for B-cell lymphomas, Hodgkin lymphoma, or a single-site nodal lymphoma documented elsewhere. If the record names a more specific mature T/NK-cell lymphoma, code that diagnosis instead.
Coding tip
Match the code to both the lymphoma type and the documented nodal distribution; if either is missing, verify the chart before coding.