New imaging techniques in the treatment guidelines for lung cancer

Computed tomography (CT) remains the main imaging technique for the preoperative staging and post-therapeutic evaluation of bronchogenic carcinoma. Spiral CT has already overcome some of the problems encountered with central or more extensive tumours. Multislice CT offers further improvement and allows for scanning of the whole chest within a single breath-hold using a thin-section high-resolution technique. Problem-adapted sections in arbitrary directions become available and provide an excellent spatial resolution. One can expect improved accuracy for the evaluation of transfissural tumour growth, chest wall involvement, mediastinal infiltration and lymph node staging. Despite recent advances in magnetic resonance (MR) techniques for imaging the chest, the role of MR for staging of bronchogenic carcinoma remains limited. It offers advantages such as the assessment of chest-wall involvement or mediastinal involvement in patients in whom CT remains equivocal. Lymph-node-specific MR contrast agents offer new diagnostic potential for the assessment of metastatic disease. New techniques for the display of three-dimensional data sets include volume rendering and virtual bronchoscopy. These techniques represent new tools for the evaluation and demonstration of pathology within the central tracheobronchial tree. Their most important application is the guidance of bronchoscopic biopsies. The assessment of an indeterminate pulmonary nodule is frequently based on positron emission tomography imaging. As an alternative, nodule vascularization (contrast enhancement patterns on CT or magnetic resonance imaging (MRI)), calcifications (absorption characteristics at various X-ray energies on CT or dual energy radiography), and morphological features (high resolution imaging at CT) can be used as the basis for nodule differentiation. The dynamics of contrast enhancement in CT or MRI can also be used for the assessment of tumour viability after chemotherapy. Lung cancer screening programmes are still controversial. Low-dose computed tomography scanning and computed assisted detection algorithms based on chest radiographs or computed tomography scans form the technical basis for such projects.