ESTRO 37 Abstract book

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ESTRO 37

chemoradiotherapy and were enrolled (median age, 66 years; range, 51-79 years). Results There were two cases of oropharyngeal cancer and ten cases of hypopharyngeal cancer. The pharyngeal tumors were relatively advanced (3, 1, and 8 patients had stage I, II, and IVA cancer, respectively), while most esophageal tumors were discovered incidentally in the early stages (1, 9, and 2 patients had stage 0, I, and II disease, respectively). All esophageal tumors presented as diffuse and superficial lesions with scattered Lugol- voiding lesions (Figure 1). Two patients had multicentric esophageal cancer. Intensity-modulated radiotherapy was successfully applied to the head and neck region in seven patients; two patients required a treatment interval of >7 days due to pneumonia. The follow-up period ranged between 13 and 76 months (median: 36 months). Table 1 shows the observed toxicities. There were no grade 4-5 toxicities; all acute reactions improved within 5 months of treatment, except for dry mouth. Four patients had recurrent hypopharyngeal cancer (local recurrence: 2; lymph node recurrence: 2). One case of esophageal cancer recurrence was successfully treated by endoscopic resection.

Conclusion In this first series of patients with resectable gastric cancer, MRI-based target volume delineation was feasible in the pre- and postoperative setting. The axial T2w TSE MRI sequence with navigator triggering in exhale provided optimal imaging quality to delineate the CTV. In further analyses, the impact of differences between pre- and postoperative CTVs on dose distribution and toxicity will be addressed. EP-1440 Extended-field chemoradiotherapy for synchronous esophageal and pharyngeal tumors: a phase one study K. Okajima 1 , T. Matsuura 1 , Y. Oguma 1 , H. Takahashi 1 , H. Tatebe 1 , K. Ishikawa 2 1 Nara hospital Kindai University, Radiology, Ikoma, Japan 2 Kindai University, Radiation Oncology, Osaka-Sayama, Japan Purpose or Objective Superficial esophageal cancer is increasingly seen in patients with oropharyngeal and hypopharyngeal tumors. We evaluated the toxicity of concurrent radiotherapy and chemotherapy in patients with both cancers, hypothesizing that the irradiated field can be safely extended to the lower esophagus in patients with pharyngeal tumors and early esophageal cancers. Material and Methods The protocol was approved by our board for head and neck tumors in April 2010. Criteria for patient selection included age (<80 years), pharyngeal cancer stage (without distant metastasis), esophageal cancer stage (0, I, or II), histologic subtype (squamous cell carcinoma for both cancers), and Eastern Cooperative Oncology Group performance status (0 or 1). The Union for International Cancer Control 7th edition criteria were applied for cancer staging. We excluded those with renal or cardiac dysfunction. Patients received 70 Gy of radiotherapy for hypopharyngeal or oropharyngeal cancer and 60 Gy for esophageal cancer (2 Gy/fraction/day, 5 days/week). Patients aged <75 years received concurrent cisplatin (70 mg/m2 on days 1 and 29) and fluorouracil (700 mg/m2 on days 1-4 and 29-32). Patients aged >75 years received weekly docetaxel or cetuximab. Between July 2010 and September 2016, 75 pharyngeal cancer (28 oropharyngeal and 47 hypopharyngeal) cases were treated. Eighteen cases had synchronous esophageal cancer; 12 men met the criteria for concurrent

Conclusion Concurrent chemoradiotherapy for pharyngeal and esophageal tumors was well tolerated. Associated esophageal cancer, often superficial and presenting as an irregularly shaped and multicentric Lugol-voiding lesion, was usually curable. EP-1441 Systematic Review of Image Guided Radiotherapy (IGRT) in Oesophageal Cancer E. Mathews 1 , S. Gwynne 2 1 South West Wales Cancer Centre, Oncology, Cardiff, United Kingdom 2 South West Wales Cancer Centre, Oncology, Swansea, United Kingdom Purpose or Objective IGRT is essential to ensure accurate radiotherapy planning and delivery in oesophageal cancer, especially