Oncology & Hematology Coding Alert

Check site of lymph nodes; distinguish mycosis fungoides vs. Sézary disease.

Cutaneous T cell lymphomas can leave you perplexed due to the unique manifestations in skin and investigations targeted to lymphomas. To get the right diagnosis code, you need to confirm if the condition in question is mycosis fungoides or Sézary disease. Once determined, you can adopt the following three step approach:

1. Check which lymph nodes are involved.
2. Confirm if more than one lymph node was affected.
3. Find out if any extra nodal sites were involved.

Site of Involved Nodes is Key

For mycosis fungoides of intrathoracic and intra-abdominal lymph nodes, you submit codes C84.02 (Mycosis fungoides, intrathoracic lymph nodes) and C84.03 (Mycosis fungoides, intra-abdominal lymph nodes), respectively.

You also have specific ICD-10-CM codes for mycosis fungoides of the lymph nodes in the extremities. For mycosis fungoides of the lymph nodes in axilla and upper limb, you submit code C84.04 (Mycosis fungoides, lymph nodes of axilla and upper limb) and for those in the inguinal region and lower limb, you submit code C84.05 (Mycosis fungoides, lymph nodes of inguinal region and lower limb). For mycosis fungoides of the lymph nodes of the pelvis, you submit code C84.06 (Mycosis fungoides, intrapelvic lymph nodes).

Not sure of the affected lymph nodes? You may encounter clinical notes with documentation of lymph nodes at multiple sites being affected. For mycosis fungoides in multiple lymph node groups, you submit code C84.08 (Mycosis fungoides, lymph nodes of multiple sites). When your physician does not document the site of the involved lymph nodes or other organs, you submit code C84.00 (Mycosis fungoides, unspecified site).

Find Codes for Specific Locations and Organs

For mycosis fungoides of the lymph nodes in head, neck, and face, you have a specific code, C84.01 (Mycosis fungoides, lymph nodes of head, face, and neck). For mycosis fungoides of the spleen, you have a definite code C84.07 (Mycosis fungoides, spleen) and for that in other solid organs, you have code C84.09 (Mycosis fungoides, extranodal and solid organ sites).

Follow the Same Norms for Sézary disease

Like in mycosis fungoides, you have the following codes for Sézary disease in lymph nodes at various sites:

• C84.11, Sézary disease, lymph nodes of head, face, and neck
• C84.12, Sézary disease, intrathoracic lymph nodes
• C84.13, Sézary disease, intra-abdominal lymph nodes
• C84.14, Sézary disease, lymph nodes of axilla and upper limb
• C84.15, Sézary disease, lymph nodes of inguinal region and lower limb
• 84.16, Sézary disease, intrapelvic lymph nodes
• C84.18, Sézary disease, lymph nodes of multiple sites.

For Sézary disease in extranodal and solid organs, you submit code C84.19 (Sézary disease, extranodal and solid organ sites) and C84.17 (Sézary disease, spleen) for that in the spleen.

When your physician does not document the site of the Sézary disease, you submit code C84.10 (Sézary disease, unspecified site).