<qa>  What is the leading cause of cancer-related death in the United States?Lung cancer is the leading cause of cancer-related death in the United States with a 5-year survival rate of 15,7.1 In lung cancer and other malignancies, such as esophageal cancer, accurate staging is essential to establish prognosis and for patient management. Staging will help determine if surgery, chemotherapy, radiation therapy, a combination of these, or a palliative approach is the most adequate.2,3 