ICD-10 Code C84.Z3 – Other Mature T/NK-Cell Lymphomas, Intra-Abdominal Lymph Nodes (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C84.Z3 – Other mature T/NK-cell lymphomas, intra-abdominal lymph nodes
What it is
This code identifies a mature T-cell or NK-cell lymphoma involving intra-abdominal lymph nodes. Use it when the record specifies this lymphoma type and nodal site, but not a more specific subtype.
Clinical signs
Clinical features vary; refer to documentation. Findings may include enlarged intra-abdominal lymph nodes, abdominal discomfort, or imaging and pathology consistent with lymphoma.
When to use this code
Use this code when the diagnosis clearly states other mature T/NK-cell lymphoma and the involved site is intra-abdominal lymph nodes. It is appropriate when pathology, oncology notes, or discharge documentation confirm the site and lymphoma category. Check documentation if the record names a different nodal region or a more specific lymphoma subtype.
Do not use for
Do not use it for unspecified lymphoma, non-nodal disease, or lymphoma in a different anatomic site. If the chart does not confirm intra-abdominal lymph node involvement, check documentation.
Coding tip
Code the exact lymphoma type and site from the final provider diagnosis, and verify that “intra-abdominal lymph nodes” is explicitly documented.