BACKGROUNDS: Lung cancer is currently the most frequently diagnosed malignant disease worldwide and radiotherapy has a fundamental and irreplaceable role in the therapeutic algorithm of this disease. Conventionally, radiotherapy is planned using CT alone. However, this could be a source of many inaccuracies and errors in the process of contouring the target volumes, the likelihood of which could be decreased by using the data from PET imaging and, ideally, from a fusion of PET and CT (as has already been proven in the diagnosis of lung cancer). CASE: This review is devoted to all important aspects related to the use of PET/CT imaging in radiotherapy treatment planning of non-small-cell lung cancer and to the advantages resulting from its use. CONCLUSION: Investigation of PET/CT imaging is a useful tool leading to increased accuracy of contouring of the target volumes. The integration of both diagnostic modalities reduces the limitations of these modalities if used separately. The use of combined PET/CT imaging often leads to an identification of a change in tumor size (it also often uncovers distant metastases) resulting in a change of treatment intention. The change of the target volume size and thus the change of irradiated volume of critical structures could lead to an increase of the dose delivered to the tumor in situations when a reduction of these volumes was reached. Investigation of PET/CT imaging also has a positive impact on subjective approach to contouring by different radiation oncologists.

Radioterapeutické a onkologické oddlení FN Plzen

The impact of PET/CT scanning on the size of target volumes, radiation exposure of organs at risk, TCP and NTCP, in the radiotherapy planning of non-small cell lung cancer