ICD-10 code for metastatic lung cancer

The ICD-10-CM code for metastatic lung cancer is C78.00 (Secondary malignant neoplasm of unspecified lung). The official index lists 18 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on C78.00.

It is also searched as lung metastases.

Within C78.0, choose C78.00 (unspecified lung) only when documentation doesn't support a more specific option: right lung (C78.01) and left lung (C78.02).

As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.

In MS-DRG v44.0, it is part of the grouping logic for DRG 180 (Respiratory Neoplasms with MCC, relative weight 1.7806), DRG 181 (Respiratory Neoplasms with CC, relative weight 1.0936) and DRG 182 (Respiratory Neoplasms without CC/MCC, relative weight 0.7439), in MDC 04 (Diseases and Disorders of the Respiratory System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.