1. Computed Tomography Contrast-enhanced helical CT of the thorax and abdomen that includes the liver and adrenal glands is the standard radiologic investigation for staging lung cancers. Detects mediastinal nodal metastases, chest wall and mediastinal invasion. Specific features in lung nodules may be diagnostic, e.g. calcifications, fat, enhancement pattern.

4. Radiological characteristics by cell type

5. Adenocarcinoma Represents 35-40% of all lung cancers. usually occurs in a peripheral location within the lung and measure <4 cm in diameter. Only 4% show cavitation Hilar or hilar and mediastinal involvement is seen in 51% of cases on chest radiography

7. Bronchoalveolar cell carcinoma Is a subtype of adenocarcinoma. Accounts for 5% of bronchogenic CA. Increased incidence in patients with interstitial lung disease, parenchymal scaring, and exogenous lipoid pneumonia. May manifest as a solitary nodule, multifocal disease, or a rapidly progressing pneumonia. Voluminous watery sputum is characteristic.

10. Squamous cell carcinoma Accounts for 25-30% of all lung cancers. Strong association with cigarette smoking. Often centrally located within the lung. Cavitation is seen in up to 82%. Commonly causes lung collapse due to their central location.