C84.0
Header — not billableMycosis fungoides
The ICD-10 code for mycosis fungoides is C84.0.
C84.0 is a non-billable header code. It groups related conditions but cannot be used on its own for reimbursement — select one of the 11 more specific codes below.
Clinical notes
Excludes1 (not coded here)
An Excludes1 note is a pure exclusion: the excluded condition and this code should never be reported together, because the two conditions cannot occur at the same time (e.g. a congenital form vs. an acquired form of the same disease).
- peripheral T-cell lymphoma, not elsewhere classified (C84.4-)
Documentation support
General coding-documentation guidance — not a substitute for payer-specific requirements or professional coding judgment.
- •This is a non-billable header code. Documentation must support a more specific child code before this diagnosis can be reported on a claim.
- •Confirm the excluded condition(s) listed above are not also present — Excludes1 conditions cannot be coded together with this one.
- •As a general rule, code to the highest level of specificity supported by the documentation in the medical record.
Child codes under C84.0
- C84.00Mycosis fungoides, unspecified site
- C84.01Mycosis fungoides, lymph nodes of head, face, and neck
- C84.02Mycosis fungoides, intrathoracic lymph nodes
- C84.03Mycosis fungoides, intra-abdominal lymph nodes
- C84.04Mycosis fungoides, lymph nodes of axilla and upper limb
- C84.05Mycosis fungoides, lymph nodes of inguinal region and lower limb
- C84.06Mycosis fungoides, intrapelvic lymph nodes
- C84.07Mycosis fungoides, spleen
- C84.08Mycosis fungoides, lymph nodes of multiple sites
- C84.09Mycosis fungoides, extranodal and solid organ sites
- C84.0AMycosis fungoides, in remission
Related codes in this category
- C84.1Sézary diseasenon-billable header
- C84.4Peripheral T-cell lymphoma, not elsewhere classifiednon-billable header
- C84.6Anaplastic large cell lymphoma, ALK-positivenon-billable header
- C84.7Anaplastic large cell lymphoma, ALK-negativenon-billable header
- C84.9Mature T/NK-cell lymphomas, unspecifiednon-billable header
- C84.ACutaneous T-cell lymphoma, unspecifiednon-billable header
- C84.ZOther mature T/NK-cell lymphomasnon-billable header
- C84.0Mycosis fungoidesnon-billable header