Onkológia 2/2023

Radiotherapy of inoperable, locally advanced non-small cell lung cancer

Radiotherapy (RT) has a strong position in the treatment of inoperable locally advanced non-small cell lung cancer (NSCLC). The objective of radical radiotherapy is devitalization of the tumor site and metastatic regional lymph nodes while preserving the dose-volume limitations for healthy tissues. Radical radiotherapy, especially radiotherapy given with concomitant chemotherapy (CHT) is a potentially curable modality. Its effectiveness is increased by the subsequent administration of durvalumab immunotherapy, which significantly improves treatment results. For RT planning, it is necessary to use at least 3DCT, ideally 4DCT or possibly in combination with PET/CT. In 4DCT, maximum intensity projection (MIP) is used, in which the internal target volume (ITV) is contoured, which makes it possible to add smaller edges to the planning target volume (PTV). Verification of individual radiation fractions must be performed using conebeam CT and image-guided radiotherapy (IGRT). Conventional fractionated regimens with a total dose of 60-70 Gy are used. If only RT is used, hypofractionated regimens are used as well. There are also ongoing studies on concomitant CHTRT using hypofractionated RT regimens. The toxicity of the treatment is significantly lower with the use of new, more advanced technologies than it was in the past, as these technologies allow the target volumes to be reduced and the surrounding healthy tissues to be spared.

Keywords: radical radiotherapy, concomitant chemoradiotherapy, non-small cell lung cancer, target volumes, toxicity