C77Secondary and unspecified malignant neoplasm of lymph nodes

C77 is the ICD-10-CM diagnosis code for secondary and unspecified malignant neoplasm of lymph nodes. It belongs to block C76-C80 (malignant neoplasms of ill-defined, other secondary and unspecified sites) and chapter 2 (neoplasms). It is a header code, so it can't be reported by itself; one of its 8 subcodes must be used instead.

To report this condition, pick the subcode that matches the documentation: C77.0 (of head, face and neck), C77.1 (nodes), C77.2 (nodes), C77.3 (nodes), C77.4 (nodes), C77.5 (nodes), C77.8 (of multiple regions) and C77.9 (unspecified).

Don't report C77 together with the conditions in its Excludes1 note: malignant neoplasm of lymph nodes, specified as primary (C81-C86, C88, C96.-), mesentery metastasis of carcinoid tumor (C7B.04) and secondary carcinoid tumors of distant lymph nodes (C7B.01).

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.