2025 ICD-10-CM Diagnosis Code C84.0

by

Mycosis fungoides

  • C84.0 should not be used for reimbursement purposes as there are multiple codes below it that contain a greater level of detail.
  • The 2025 edition of ICD-10-CM C84.0 became effective on October 1, 2024.
  • This is the American ICD-10-CM version of C84.0 – other international versions of ICD-10 C84.0 may differ.

Type 1 Excludes

  • peripheral T-cell lymphoma, not elsewhere classified (C84.4-)

The following code(s) above C84.0 contain annotation back-references

 that may be applicable to C84.0:

  • C00-D49  Neoplasms
  • C81-C96  Malignant neoplasms of lymphoid, hematopoietic and related tissue
  • C84  Mature T/NK-cell lymphomas

Clinical Information

  • A chronic, malignant t-cell lymphoma of the skin. In the late stages, the lymph nodes and viscera are affected.
  • A kind of skin cancer
  • A peripheral (mature) t-cell lymphoma presenting in the skin with patches/plaques. It is characterized by epidermal and dermal infiltration of small to medium-sized t-cells with cerebriform nuclei. Patients with limited disease generally have an excellent prognosis. In the more advanced stages, the prognosis is poor. (who, 2001)
  • A type of non-hodgkin’s lymphoma that first appears on the skin and can spread to the lymph nodes or other organs such as the spleen, liver, or lungs.
  • Chronic malignant t-cell lymphoma of the skin; in the late stages the lymph nodes and viscera are affected.

Code History

  • 2016 (effective 10/1/2015): New code (first year of non-draft ICD-10-CM)
  • 2017 (effective 10/1/2016): No change
  • 2018 (effective 10/1/2017): No change
  • 2019 (effective 10/1/2018): No change
  • 2020 (effective 10/1/2019): No change
  • 2021 (effective 10/1/2020): No change
  • 2022 (effective 10/1/2021): No change
  • 2023 (effective 10/1/2022): No change
  • 2024 (effective 10/1/2023): No change
  • 2025 (effective 10/1/2024): No change

Diagnosis Index entries containing back-references to C84.0:

error: Content is protected !!