Alphabetic Index FY2027

C77

Secondary and unspecified malignant neoplasm of lymph nodes

FY2027Chapter 2: Neoplasms/C76–C80 Malignant neoplasms of ill-defined, other secondary and unspecified sites

Non-billable headerNot valid on its own. Use one of the more specific codes under it.

C77 is a non-billable ICD-10-CM code category for secondary and unspecified malignant neoplasm of lymph nodes. Report a more specific code from it instead. It is part of the FY2027 code set, effective October 1, 2026. The more specific codes under it are C77.0 Secondary and unspecified malignant neoplasm of lymph nodes of head, face and neck; C77.1 Secondary and unspecified malignant neoplasm of intrathoracic lymph nodes; C77.2 Secondary and unspecified malignant neoplasm of intra-abdominal lymph nodes; C77.3 Secondary and unspecified malignant neoplasm of axilla and upper limb lymph nodes and 4 more. Its coding notes include 3 Excludes1 entries.

Guidelines tip

From the FY2027 Official Guidelines. ICD10Ref adds no rules of its own.

When treatment is directed only at the metastatic site, the secondary site is first-listed and the primary malignancy is an additional code.

Guidelines I.C.2.l.2Treatment directed at a secondary siteRead the official text

Excludes1

Not coded here. The listed conditions generally should not be reported together.

This code
  • malignant neoplasm of lymph nodes, specified as primary (C81-C86, C88, C96.-)
  • mesentery metastasis of carcinoid tumor (C7B.04)
  • secondary carcinoid tumors of distant lymph nodes (C7B.01)

Notes

Also from chapter/block level (8 notes)
Inherited from Chapter 2 Neoplasms
  • Functional activity
  • All neoplasms are classified in this chapter, whether they are functionally active or not. An additional code from Chapter 4 may be used, to identify functional activity associated with any neoplasm.
  • Morphology [Histology]
  • Chapter 2 classifies neoplasms primarily by site (topography), with broad groupings for behavior, malignant, in situ, benign, etc. The Table of Neoplasms should be used to identify the correct topography code. In a few cases, such as for malignant melanoma and certain neuroendocrine tumors, the morphology (histologic type) is included in the category and codes.
  • Primary malignant neoplasms overlapping site boundaries
  • A primary malignant neoplasm that overlaps two or more contiguous (next to each other) sites should be classified to the subcategory/code .8 ('overlapping lesion'), unless the combination is specifically indexed elsewhere. For multiple neoplasms of the same site that are not contiguous, such as tumors in different quadrants of the same breast, codes for each site should be assigned.
  • Malignant neoplasm of ectopic tissue
  • Malignant neoplasms of ectopic tissue are to be coded to the site mentioned, e.g., ectopic pancreatic malignant neoplasms are coded to pancreas, unspecified (C25.9).

More specific codes under C77 8