ICD-10 Code C83.51 – Lymphoblastic (diffuse) lymphoma, lymph nodes of head, face, and neck (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C83.51 – Lymphoblastic (diffuse) lymphoma, lymph nodes of head, face, and neck
What it is
This code identifies lymphoblastic lymphoma involving lymph nodes in the head, face, or neck. It is used when documentation specifies this anatomic site and the diagnosis is lymphoblastic (diffuse) lymphoma.
Clinical signs
Clinical features vary; refer to documentation. Common findings may include enlarged cervical or facial lymph nodes, a rapidly enlarging mass, or other signs consistent with lymphoma.
When to use this code
Use C83.51 when the provider documents lymphoblastic lymphoma and clearly states the involved lymph nodes are in the head, face, or neck. It is appropriate for pathology-confirmed disease, oncology assessments, or discharge diagnoses that specify this location. Check documentation if the site is described only generally.
Do not use for
Do not use this code if the lymphoma site is elsewhere or if the record only says lymphoma without the lymph node location. Do not assign it for other lymphoma subtypes. Check documentation.
Coding tip
Code the exact anatomic site only when the chart states it explicitly; otherwise, query for clarification.