C39Malignant neoplasm of other and ill-defined sites in the respiratory system and intrathoracic organs

C39 is the ICD-10-CM diagnosis code for malignant neoplasm of other and ill-defined sites in the respiratory system and intrathoracic organs. It belongs to block C30-C39 (malignant neoplasms of respiratory and intrathoracic organs) and chapter 2 (neoplasms). It is a header code, so it can't be reported by itself; one of its 2 subcodes must be used instead.

To report this condition, pick the subcode that matches the documentation: C39.0 (unspecified) and C39.9 (unspecified).

Don't report C39 together with the conditions in its Excludes1 note: intrathoracic malignant neoplasm NOS (C76.1) and thoracic malignant neoplasm NOS (C76.1).

Use an additional code to identify: exposure to environmental tobacco smoke (Z77.22), exposure to tobacco smoke in the perinatal period (P96.81), history of tobacco dependence (Z87.891), occupational exposure to environmental tobacco smoke (Z57.31), tobacco dependence (F17.-) and 1 more.

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