Staging for M disease.

The presence of distant metastatic disease (M disease) in non-small-cell cancer patients is associated with a poor prognosis, and surgical resection at the primary site is contraindicated. Careful preoperative evaluation to identify the subset of patients presenting with M disease is essential in order to avoid unnecessary surgery. Current indications for the use of diagnostic techniques and the methods utilized to detect metastatic disease at the commonest sites encountered in patients with non-small-cell carcinoma, including the pleura, central nervous system, liver, adrenal glands, and skeletal system, are discussed.