ICD-10 Code C85.27 – Mediastinal (thymic) large B-cell lymphoma, spleen (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C85.27 – Mediastinal (thymic) large B-cell lymphoma, spleen
What it is
This code identifies mediastinal (thymic) large B-cell lymphoma involving the spleen. Use it when the record documents this specific lymphoma subtype with splenic involvement.
Clinical signs
Clinical features vary; refer to documentation. Commonly, records may note lymphadenopathy, splenic enlargement, or imaging and pathology confirming large B-cell lymphoma in the mediastinal/thymic type.
When to use this code
Use C85.27 when the provider documents mediastinal (thymic) large B-cell lymphoma and specifies the spleen as involved or affected. It also fits when pathology, imaging, or oncology notes clearly link the lymphoma to splenic disease.
If the site is not specified, or the chart only says lymphoma without this subtype, check documentation before coding. Confirm that splenic involvement is not being described for a different lymphoma type.
Do not use for
Do not use this code for other non-Hodgkin lymphomas, unspecified lymphoma, or mediastinal masses without confirmed lymphoma. Do not assume splenic involvement unless the documentation states it.
Coding tip
Verify both the lymphoma subtype and the splenic site in the same record before assigning C85.27.