ICD-10 Code C83.5 – Lymphoblastic (diffuse) lymphoma (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C83.5 – Lymphoblastic (diffuse) lymphoma
What it is
C83.5 identifies lymphoblastic (diffuse) lymphoma, an aggressive non-Hodgkin lymphoma of immature lymphoid cells. You use it when the record documents this specific diagnosis, not a generic lymphoma type.
Clinical signs
Clinical features vary; refer to documentation. Commonly recorded findings include rapidly enlarging lymph nodes, mediastinal mass, or other extranodal involvement consistent with an aggressive lymphoid malignancy.
When to use this code
Use C83.5 when the provider clearly documents lymphoblastic lymphoma, including “diffuse” lymphoblastic lymphoma. It is appropriate for confirmed diagnoses in inpatient, outpatient, and problem-list coding when the condition is active or being evaluated.
If the chart only says “lymphoma” or another subtype without confirmation, check documentation before assigning this code. Code the documented malignant neoplasm as specifically as possible.
Do not use for
Do not use C83.5 for acute lymphoblastic leukemia, unspecified non-Hodgkin lymphoma, or Hodgkin lymphoma. Check documentation if the pathology report does not clearly support lymphoblastic lymphoma.
Coding tip
Confirm the exact lymphoma subtype in pathology or oncology notes before coding, because “lymphoblastic” and “leukemia” are not interchangeable.