ICD-10 Code C85.2 – Mediastinal (thymic) large B-cell lymphoma (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C85.2 – Mediastinal (thymic) large B-cell lymphoma
What it is
This code identifies a primary large B-cell lymphoma arising in the mediastinum, often from thymic tissue. Use it when documentation specifies mediastinal or thymic large B-cell lymphoma.
Clinical signs
Clinical features vary; refer to documentation. Commonly reported findings include a mediastinal mass, cough, chest pain, shortness of breath, or superior vena cava compression.
When to use this code
Use C85.2 when the provider documents mediastinal (thymic) large B-cell lymphoma as the diagnosis. It also applies when pathology or oncology notes clearly identify this specific lymphoma site and type. If the record only says “large B-cell lymphoma” without mediastinal involvement, check documentation.
Do not use for
Do not use this code for other non-Hodgkin lymphomas, Hodgkin lymphoma, or unspecified lymphoma. Avoid it when the mediastinal mass is not confirmed as lymphoma.
Coding tip
Code the documented lymphoma subtype and anatomic site exactly as stated; if either is unclear, check documentation before assigning C85.2.