ICD-10 Code C85.16 – Unspecified B-cell lymphoma, intrapelvic lymph nodes (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C85.16 – Unspecified B-cell lymphoma, intrapelvic lymph nodes
What it is
This code identifies a B-cell lymphoma involving the intrapelvic lymph nodes when the exact lymphoma type is not documented. Use it for malignant lymphoid disease limited to, or centered in, pelvic lymph nodes.
Clinical signs
Clinical features vary; refer to documentation. Patients may have pelvic lymphadenopathy found on imaging, biopsy, or examination, with nonspecific findings such as a mass or local pressure symptoms.
When to use this code
Use C85.16 when the record states unspecified B-cell lymphoma and names intrapelvic lymph nodes as the site. It fits cases where pathology confirms B-cell lymphoma, but the subtype is not further defined. If the documentation identifies a more specific lymphoma, code that instead.
Do not use for
Do not use this code for Hodgkin lymphoma, T-cell lymphomas, or lymphomas documented outside the intrapelvic lymph nodes. Check documentation if the site is uncertain or if the diagnosis is only suspected.
Coding tip
Verify both the lymphoma type and anatomic site in the pathology or oncology note before assigning C85.16.