Lung cancer is a sort of cancer that starts within the lungs. Cancer starts when cells within the body begin to grow out of control. The delay in diagnosis of lung cancer worsens prognosis of the disease. Reducing diagnostic delay could reduce mortality. Lung cancer is one among the leading causes of death in the world. The 2 sorts of lung cancer, which grow and spread differently, are small-cell lung cancers (SCLC) and non-small-cell lung cancers (NSCLC). Health professionals also refer to them as small-cell lung carcinoma and non-small-cell lung carcinoma. About 80% to 85% of lung cancers are non-small-cell lung carcinoma. Subtypes of non-small cell lung carcinoma are adenocarcinoma, squamous cell carcinoma, and large cell carcinoma. These subtypes, which start from different types of lung cells are grouped together as NSCLC because their treatment and prognoses are often similar. About 10% to 15 of all lung cancers are SCLC and it’s sometimes called oat cell cancer. Signs and symptoms of lung cancer may include: cough that doesn’t go away, coughing up blood, even a small amount, shortness of breath, chest pain, hoarseness, losing weight without trying, bone pain, headache.