ICD-10-CM > C00-D49 > C76-C80 > C78 > C78.0 C78.0 Secondary malignant neoplasm of lung Non-Billable/Non-Specific Codes C78.00Secondary malignant neoplasm of unspecified lungC78.01Secondary malignant neoplasm of right lungC78.02Secondary malignant neoplasm of left lung