![]() In particular, a significantly lower incidence of pulmonary and cardiac late side effects could be achieved by the advancement from 3-dimensional conformal radiotherapy to intensity-modulated radiation therapy (IMRT) techniques. However, the introduction and establishment of novel irradiation techniques in radiotherapy led to an improvement of previously observed complications. There is a multitude of data from various studies that point out the pertinence of administered radiotherapy dose concerning cardiac and pulmonary complications. The complexity of the problem is in protecting as much as possible the nearby organs while maintaining adequate target coverage for the target volumes. ĭue to the anatomic location of the oesophagus near to several organs at risk, such as the lungs, heart, spinal cord and stomach, the irradiation of oesophagal carcinomas is challenging. The radiation dose, which is usually applied in the course of neoadjuvant radiochemotherapy, is mostly based on the protocol of the CROSS study with a total dose of 41.4 Gy in fractions of 1.8 Gy. In adenocarcinoma, either perioperative chemotherapy or neoadjuvant radiochemotherapy can be performed. Neoadjuvant radiochemotherapy is regarded as the standard of care in squamous cell carcinoma. These include surgical resection, chemotherapy and radiotherapy. Oncological management of locally advanced oesophagal cancer depends on the histopathological findings and contains a diversity of multimodal treatment options. Despite curative intended multimodal treatment approaches, prognosis, especially in locally advanced tumours, remains poor. Oesophagal cancer is a particularly aggressive and common tumour entity with an estimated annual incidence of 572,000 new oesophagal cancer cases and 508,000 deaths worldwide in 2018. Furthermore, reduced risk of secondary neoplasia in the lung can be expected in long-term survivors and would be a great gain for cured patients. In particular, the reduction of the heart and abdominal structures dose could result in an optimised side effect profile. With regard to cancer of the oesophagogastric junction type I and II, the use of intensity-modulated proton therapy seems to have a clear advantage over VMAT. For the coronaries, the RR resulted in 1.6 ± 0.4 for RA_RP and 1.2 ± 0.3 for protons. The RR for the left ventricle resulted in 1.5 ± 0.1 for RA_RP and 1.1 ± 0.1 for both IMPT sets. The EAR per 10,000 patients-years of secondary cancer induction resulted in 19.2 ± 5.7 for RA_RP and 6.1 ± 2.7 for IMPT_2F or 5.7 ± 2.4 for IMPT_3F. Similar sparing effects were observed for the liver, the kidneys, the stomach, the spleen and the bowels. The mean dose to the whole heart resulted to 9.9 ± 1.9 Gy for RA_RP compared to 3.7 ± 1.3 Gy or 4.0 ± 1.4 Gy for IMPT_2F or IMPT_3F the mean dose to the left ventricle resulted to 6.5 ± 1.6 Gy, 1.9 ± 1.5 Gy, 1.9 ± 1.6 Gy respectively. Concerning the organs at risk, the IMPT plans showed a systematic and statistically significant incremental sparing when compared to RA_RP, especially for the heart. Resultsīoth the RA_RP and IMPT approached allowed to achieve the required coverage for the gross tumour volume, (GTV) and the clinical and the planning target volumes, CTV and PTV (V 98% > 98 for CTV and GTV and V 95% > 95 for the PTV)). For the cardiac structures, the relative risk (RR) of coronary artery disease (CAD) and chronic heart failure (CHF) were estimated. Estimates of the excess absolute risk (EAR) of secondary cancer induction were determined for the lungs. Twenty patients were retrospectively planned for IMPT (with two fields, (IMPT_2F) or with three fields (IMPT_3F)) and RA_RP and the results were compared according to dose-volume metrics. To investigate the role of intensity-modulated proton therapy (IMPT) compared to volumetric modulated arc therapy (VMAT), realised with RapidArc and RapidPlan methods (RA_RP) for neoadjuvant radiotherapy in locally advanced oesophagal cancer.
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