C77.9 — Secondary and unspecified malignant neoplasm of lymph node, unspecified

BillableUnspecifiedCC

Is C77.9 billable?

Yes, but C77.9 is an unspecified code. C77.9 is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, C77.9 is an unspecified or catch-all code. Payers apply additional scrutiny to unspecified codes and many deny them when the medical record supports a more specific option, so check the documentation before selecting C77.9 — the more specific alternatives are listed below.

More specific alternatives

C77.9 at a glance

Code	C77.9
Description	Secondary and unspecified malignant neoplasm of lymph node, unspecified
Billable	Yes
Code set	ICD-10-CM FY2027
Valid for encounters	October 1, 2026 – September 30, 2027

Which MS-DRGs does C77.9 group to?

C77.9 sits in MDC 17 and helps define the logic of 3 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.

820Lymphoma and Leukemia with Major O.R. Procedures with MCCsurgical
821Lymphoma and Leukemia with Major O.R. Procedures with CCsurgical
822Lymphoma and Leukemia with Major O.R. Procedures without CC/MCCsurgical

As a secondary diagnosis, C77.9 is a complication or comorbidity (CC), which can move a stay into a higher-paying DRG.

Excludes1 — never code together — inherited from C77

The conditions below can never be reported together with C77.9 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.

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)

How long has C77.9 existed?

C77.9 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.

Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.