title: Dose-Response Relationship between Radiation Dose and Loco-regional Control in Patients with Stage II-III Esophageal Cancer Treated with Definitive Chemoradiotherapy.
abstract: OBJECTIVE
  The correlation between radiation dose and loco-regional control (LRC) was evaluated in patients with stage II-III esophageal cancer treated with definitive concurrent chemoradiotherapy (CRT).
  
  
  METHODS
  Medical records of 236 stage II-III esophageal cancer patients treated with definitive CRT at Yonsei Cancer Center between 1994 and 2013 were retrospectively reviewed. Among these, 120 received a radiation dose of < 60 Gy (standard-dose group), while 116 received ≥ 60 Gy (high-dose group). The median doses of radiation in the standard- and high-dose groups were 50.4 and 63 Gy, respectively. Concurrent 5-fluorouracil/cisplatin chemotherapy was administered to most patients.
  
  
  RESULTS
  There were no differences in patient characteristics between the two groups except for high Karnofsky performance status and lower-thoracic lesions being more prevalent in the standard-dose group. The median progression-free survival (PFS) and overall survival (OS) times were 13.2 months and 26.2 months, respectively. Patients in the high-dose group had significantly better 2-year LRC (69.1% vs. 50.3%, p=0.002), median PFS (16.7 months vs. 11.7 months, p=0.029), and median OS (35.1 months vs. 22.3 months, p=0.043). Additionally, LRC exhibited a dose-response relationship and the complete response rate was significantly higher in the high-dose group (p=0.006). There were no significant differences in treatment-related toxicities between the groups.
  
  
  CONCLUSIONS
  A higher radiation dose (> 60 Gy) is associated with increased LRC, PFS, and OS in patients with stage II-III esophageal cancer treated with definitive CRT.
authors.affiliation: Department of Radiation Oncology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Hyun Ju
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Radiation Oncology, National Cancer Center, Goyang, Korea.
authors.forename: Yang-Gun
authors.initials: YG
authors.lastname: Suh
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Yong Chan
authors.initials: YC
authors.lastname: Lee
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Sang Kil
authors.initials: SK
authors.lastname: Lee
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Sung Kwan
authors.initials: SK
authors.lastname: Shin
authors.affiliation: Division of Medical Oncology, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Byung Chul
authors.initials: BC
authors.lastname: Cho
authors.affiliation: Department of Radiation Oncology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Chang Geol
authors.initials: CG
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D059248:Chemoradiotherapy / Q000009:adverse effects / Q000379:methods; D003131:Combined Modality Therapy; D004307:Dose-Response Relationship, Radiation; D004938:Esophageal Neoplasms / Q000401:mortality / Q000473:pathology* / Q000628:therapy*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D016016:Proportional Hazards Models; D011879:Radiotherapy Dosage; D016896:Treatment Outcome; D047368:Tumor Burden
keywords: Chemoradiotherapy; Esophageal neoplasms; Radiation dose-response relationship