Fig. 1

The overall survival of: (A) the whole cohort. (B) cervical/upper thoracic ESCA. (C) standard dose(50–55 Gy)and high dose (>55 Gy) for cervical ESCA. (D) standard dose (50–55 Gy) and high dose (>55 Gy) for upper thoracic ESCA. ESCA: Esophageal cancer