ICD-10 Code C83.30 – Diffuse large B-cell lymphoma, unspecified site (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C83.30 – Diffuse large B-cell lymphoma, unspecified site
What it is
This code identifies diffuse large B-cell lymphoma when the record does not specify the anatomic site. It is a fast-growing non-Hodgkin lymphoma arising from B cells.
Clinical signs
Clinical features vary; refer to documentation. Common findings include enlarged lymph nodes, extranodal masses, and systemic “B” symptoms such as fever, night sweats, or weight loss.
When to use this code
Use C83.30 when the provider documents diffuse large B-cell lymphoma but does not name a site. Apply it for confirmed diagnoses in pathology, oncology, or discharge documentation when the location is unspecified.
If the record later identifies a specific site, code the documented site instead. Check documentation when the chart includes multiple lymph node regions or extranodal involvement.
Do not use for
Do not use this code for other lymphoma subtypes, suspected lymphoma, or lymphoma with a clearly documented site. Check documentation if the diagnosis is incomplete or uncertain.
Coding tip
Confirm that “diffuse large B-cell lymphoma” is explicitly stated and that no site is documented before assigning C83.30.