ICD-10 Code C77.3 – Secondary and unspecified malignant neoplasm of axilla and upper limb lymph nodes (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C77.3 – Secondary and unspecified malignant neoplasm of axilla and upper limb lymph nodes
What it is
This code identifies metastatic malignant disease involving lymph nodes in the axilla or upper limb. Use it when a primary cancer has spread to these regional nodes, or when the site is documented as secondary but not further specified.
Clinical signs
Findings may include enlarged, firm, or fixed nodes in the axilla or upper extremity drainage area. Clinical features vary; refer to documentation and pathology or imaging reports when available.
When to use this code
Use C77.3 when the record clearly documents metastatic involvement of axillary or upper limb lymph nodes from a known malignancy. It also applies when the provider describes secondary malignant neoplasm at this site without naming a more specific nodal group. Confirm the primary cancer is coded separately when documented.
Do not use for
Do not use this code for primary lymph node cancers or for benign lymphadenopathy. Check documentation if the node enlargement is reactive, inflammatory, or unspecified without evidence of metastasis.
Coding tip
Verify the metastatic site and code the primary malignancy first when both are documented.