ICD-10 Code C84.08 – Mycosis fungoides, lymph nodes of multiple sites (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C84.08 – Mycosis fungoides, lymph nodes of multiple sites
What it is
C84.08 identifies mycosis fungoides involving lymph nodes at multiple sites. Use it when documentation shows this cutaneous T-cell lymphoma has spread to or is affecting more than one lymph node region.
Clinical signs
Clinical features vary; refer to documentation. Typical records may note persistent skin lesions with lymph node enlargement, biopsy-confirmed mycosis fungoides, or staging evidence of nodal involvement in multiple sites.
When to use this code
Use this code when the provider documents mycosis fungoides with involvement of lymph nodes in multiple anatomic regions. It may also apply when staging or pathology clearly states nodal spread beyond a single site. If the record only says “lymph node involvement” without locations, check documentation.
Do not use for
Do not use this code for mycosis fungoides limited to skin, a single lymph node region, or unspecified nodal disease. Check documentation if the diagnosis is another lymphoma or a nonspecific skin disorder.
Coding tip
Confirm that the chart names both mycosis fungoides and multiple lymph node sites before assigning C84.08.