ICD-10 Code C85.19 – Unspecified B-cell lymphoma, extranodal and solid organ sites (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C85.19 – Unspecified B-cell lymphoma, extranodal and solid organ sites
What it is
This code identifies a B-cell lymphoma found in an extranodal or solid organ site when the record does not specify the exact subtype. Use it for malignant lymphoid disease outside lymph nodes with incomplete histologic detail.
Clinical signs
Clinical features vary; refer to documentation. Commonly, the chart may describe a mass, organ enlargement, pain, or other site-specific findings, with pathology confirming B-cell lymphoma but not naming a more specific type.
When to use this code
Use C85.19 when the provider documents an unspecified B-cell lymphoma involving an extranodal or solid organ site and no more specific lymphoma code is supported. It fits cases where pathology or clinical notes confirm B-cell lineage, but the exact subtype remains unclear. Check documentation if the site or histology is ambiguous.
Do not use for
Do not use this code when the lymphoma type is specified more precisely, such as a named B-cell lymphoma subtype. It is also not appropriate for nodal-only lymphoma or non-lymphoma malignancies.
Coding tip
Query the provider when the pathology report names a specific lymphoma subtype or the involved site is unclear.