C78 – Secondary malignant neoplasm of respiratory and digestive organs

ICD-10-CM 2027 diagnosis code · Malignant neoplasms of ill-defined, other secondary and unspecified sites

Non-billable header

ICD-10-CM code C78

Code: C78 (claims format: C78)
Description: Secondary malignant neoplasm of respiratory and digestive organs
Short description: Secondary malignant neoplasm of resp and digestive organs
Billable: No – use a more specific code below
Valid for: Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter: 2. Neoplasms (C00-D49)
Block: C76-C80 Malignant neoplasms of ill-defined, other secondary and unspecified sites

Billable codes under C78

C78 is a header code and cannot be used on claims. Choose the most specific code:

C78.0 – Secondary malignant neoplasm of lungHeader (more codes below)
C78.1 – Secondary malignant neoplasm of mediastinumBillable
C78.2 – Secondary malignant neoplasm of pleuraBillable
C78.3 – Secondary malignant neoplasm of other and unspecified respiratory organsHeader (more codes below)
C78.4 – Secondary malignant neoplasm of small intestineBillable
C78.5 – Secondary malignant neoplasm of large intestine and rectumBillable
C78.6 – Secondary malignant neoplasm of retroperitoneum and peritoneumBillable
C78.7 – Secondary malignant neoplasm of liver and intrahepatic bile ductBillable
C78.8 – Secondary malignant neoplasm of other and unspecified digestive organsHeader (more codes below)

Notes for C78

Excludes1 (not coded here):

secondary carcinoid tumors of liver (C7B.02)
secondary carcinoid tumors of peritoneum (C7B.04)

Excludes2 (not included here):

lymph node metastases (C77.0)

Frequently asked questions

What is ICD-10 code C78?

C78 is the ICD-10-CM code for secondary malignant neoplasm of respiratory and digestive organs, in the block C76-C80 (Malignant neoplasms of ill-defined, other secondary and unspecified sites).

Is C78 a billable code?

No. C78 is a header code with more specific child codes; report one of the billable codes listed above.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.