ICD-10 Code C85.25 – Mediastinal (thymic) large B-cell lymphoma, lymph nodes of inguinal region and lower limb (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C85.25 – Mediastinal (thymic) large B-cell lymphoma, lymph nodes of inguinal region and lower limb
What it is
This code identifies a large B-cell lymphoma arising in the mediastinum or thymus and involving lymph nodes of the inguinal region or lower limb. Use it when documentation names this specific lymphoma and nodal site.
Clinical signs
Clinical features vary; refer to documentation. Patients may have a mediastinal mass, enlarged inguinal nodes, or other lymphoma findings confirmed by pathology and imaging.
When to use this code
Use this code when the provider documents mediastinal (thymic) large B-cell lymphoma with involvement of inguinal or lower-limb lymph nodes. It is appropriate when the site and histology are both clearly stated. If the record only says “lymphoma” or another nodal region, check documentation.
Do not use for
Do not use this code for unspecified lymphoma, other large B-cell lymphoma subtypes, or lymph node disease without mediastinal/thymic origin. Check documentation if the anatomic site is different.
Coding tip
Code the exact lymphoma type and documented nodal location together; if either element is missing, query the record before assigning C85.25.