ICD-10 Code C83.18 – Mantle cell lymphoma, lymph nodes of multiple sites (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C83.18 – Mantle cell lymphoma, lymph nodes of multiple sites
What it is
C83.18 identifies mantle cell lymphoma involving lymph nodes at multiple sites. Use it when the record documents this specific B-cell non-Hodgkin lymphoma pattern and nodal distribution.
Clinical signs
Clinical features vary; refer to documentation. Common findings may include enlarged lymph nodes in more than one region, with pathology confirming mantle cell lymphoma.
When to use this code
Use C83.18 when the provider documents mantle cell lymphoma affecting multiple lymph node sites, such as cervical, axillary, and inguinal nodes. Code it from pathology, oncology, or discharge documentation that clearly states both the diagnosis and the nodal distribution. Check documentation if the site is unspecified or only one nodal region is named.
Do not use for
Do not use this code for mantle cell lymphoma limited to a single lymph node region or for non-nodal extranodal disease. If the record does not specify multiple lymph node sites, check documentation.
Coding tip
Match the code to the exact anatomic extent documented; “multiple sites” must be explicit in the record.