Histologic Classification of Lung Cancer
Solitary Pulmonary Nodule
Diagnosis of Lung Cancer
Understand the epidemiology of lung cancer and etiologic factors that cause this disease.
Review the latest information on screening for lung cancer, using chest radiography and chest CT scan imaging.
Review the techniques and strategies used to diagnose lung cancer.
Understand the importance of accurate staging and review the methods used to stage a patient before treatment.
Understand the appropriate preoperative evaluation for patients who are being considered for surgical resection of a lung cancer.
Review the treatment options by stage and cell type of lung cancer.
Lung cancer is the leading cause of cancer death in the United States and worldwide, accounting for 157,000 deaths in the United States in 2011. Screening using chest radiograph does not reduce mortality. A recent randomized trial showed that screening with chest CT scan imaging reduces mortality by 20%. The diagnosis of lung cancer can be made by using a myriad of tests, depending on the size and location of the primary tumor and/or the presence and site of metastases. The initial biopsy analysis should attempt to both make a diagnosis and confirm the most advanced stage simultaneously. Lung cancer is classified as small cell (20%) and non-small cell (80%). Adenocarcinoma is the most common histologic subclass (30%–35%), then squamous cell (25%), large cell (10%–15%), and poorly differentiated non-small cell lung cancer (NSCLC) (10%–15%). Staging with CT and PET scans should be performed in most cases of lung cancer. Tissue confirmation of positive findings is needed. Accurate staging of the mediastinum is critical and can be accomplished with transbronchial needle aspirate, endobronchial ultrasound with fine needle aspiration, mediastinoscopy, mediastinotomy, or video-assisted thoracoscopic surgery. Treatment regimen and prognosis depend upon stage. Small cell lung cancer is treated with chemotherapy for advanced stage and chemoradiotherapy for limited-stage disease. Stage 1 NSCLC is treated with surgery alone; stage 2, with surgery followed by chemotherapy; stage 3, with chemoradiotherapy; and stage 4, with chemotherapy alone. Newer treatment with targeted agents, such as the tyrosine kinase inhibitors, is warranted for those with a sensitizing receptor on the surface of the tumor.