Screening, staging, and diagnostic investigation of non-small cell lung cancer patients

Despite its appeal, lung cancer screening has been found to be of little value at this time. However, use of monoclonal antibodies to detect cancer cells in the sputum may prove to be of value in high-risk subjects. Once a cancer is diagnosed, anatomic staging by the International TNM Staging System has shown its effectiveness in directing the appropriate therapeutic interventions and predicting prognosis. Anatomic staging cannot be completely accomplished by computed tomography scans or magnetic resonance imaging of the chest, particularly relative to mediastinal lymph node involvement or to direct mediastinal extension of the tumor. To determine lymph node involvement, preoperative mediastinal exploration is indicated for all potentially operable patients in whom the lymph nodes are 1 cm or greater. Although a small percentage of normal-sized lymph nodes will contain tumor, routine investigation is not believed necessary. Direct mediastinal invasion as suggested by the computed tomography scan is most often indeterminate and thoracotomy is necessary in most instances to determine the resectability of the tumor. Data continue to accumulate showing that routine scanning of asymptomatic patients for the presence of metastatic disease to the brain or skeletal system is not effective.