Seminars in respiratory and critical care medicine
-
Semin Respir Crit Care Med · Jun 2008
ReviewWho is at high risk for lung cancer? Population-level and individual-level perspectives.
Lung cancer is the leading cause of cancer death in the world. However, there is large geographic variation internationally and within nations. Despite the fact that many causes of lung cancer have been established, cigarette smoking is the principal cause. ⋯ Many lung cancer risk factors have been identified, but active cigarette smoking is the predominant cause of lung cancer and the principal marker of both high-risk populations and high-risk individuals. In the absence of cigarette smoking, lung cancer would be a rare disease. Strategies that effectively prevent youths from starting to smoke and that promote cessation among dependent smokers can transform populations from high risk to low risk.
-
Prognosis of lung cancer is markedly improved when cancers are resected in early stages (particularly in stage I). Previous investigations failed to show benefit with use of chest radiographs or sputum cytologies to screen for lung cancer among high-risk populations. ⋯ However, whether screening CT reduces death from lung cancer has not been clarified. This review examines the problem presented by lung cancer, the issues presented by screening, and the results of past and recent studies of lung cancer screening.
-
Semin Respir Crit Care Med · Jun 2008
ReviewBronchoscopy for the diagnosis and staging of lung cancer.
Bronchoscopy is an invaluable tool utilized for the diagnosis, staging, and management of lung cancer. Advancements in computer technology and engineering have allowed for the emergence of newer modalities to evaluate endobronchial, parenchymal, and mediastinal pathology. Established techniques such as white light video bronchoscopy and its ancillary procedures (forceps biopsy, brush biopsy, bronchoalveolar lavage, bronchial washings, and transbronchial needle aspiration) are discussed here, with their accuracy described in relation to tumor location, size, and type. ⋯ Special emphasis has been placed on their role in the early detection and staging of lung cancer. Some technology requires further study to delineate its role in the disease, whereas other modalities are emerging as the new gold standard in evaluation of lung cancer. The future holds great promise with further miniaturization of equipment and improvements in computer processing power that may allow for in vivo pathological evaluation of abnormal tissue.
-
Semin Respir Crit Care Med · Jun 2008
ReviewTargeted therapy in advanced non-small-cell lung cancer.
Molecularly targeted therapies have recently expanded the options available for patients with advanced non-small-cell lung cancer (NSCLC). Two cancer cell pathways in particular have been exploited, the epidermal growth factor receptor (EGFR) and the vascular endothelial growth factor (VEGF) pathway. The former has emerged as a key regulator of cancer cell proliferation and invasion, and several EGFR inhibitors have been developed. ⋯ Because preclinical data suggest a synergistic effect when VEGF and EGFR inhibitors are combined, the concurrent use of erlotinib and bevacizumab has additionally been evaluated in a phase II trial, with encouraging early results suggesting at least equivalent activity to standard salvage chemotherapy, with less toxicity. Several other novel agents are being examined, including inhibitors of histone deacteylases and the 26S proteosome. Research efforts are currently focusing on tailoring such therapies according to predictive clinical and molecular markers.
-
The past decade has seen steady advances in the field of radiation therapy, impacting definitive treatment options for early and advanced tumors, as well as identifying further roles for adjuvant and palliative therapy. The widespread availability of (18)F-fluoro-2-deoxy-D-glucose positron emission tomographic (FDG PET) imaging has improved staging, and better defines a population that will benefit from aggressive local therapy. Technological advances in radiation treatment planning allow for less normal lung irradiation, allowing increasing dose and decreasing normal tissue toxicity. Ongoing clinical investigations in the role of radiosurgery for early lung tumors, postoperative radiation of locally advanced non-small-cell lung cancer (NSCLC), and prophylactic cranial irradiation in small-cell lung cancer (SCLC) help to identify patients who may benefit from treatment.