2.1 Patients
There are 31 patients (41 lesions) with recurrent NPC after EBRT from February 2003 to January 2019 reviewed retrospectively, among which 11 patients (35.5%) treated with twice or more times EBRT and the median previous radiation doses were 71.9 (range 60-160) Gy. 17 patients with CT-guided RSI-BT only and 14 of patients with CT-guidance combined with 3D-PT assistant RSI-BT were performed under standard operating procedure in our institution. Informed consent was signed by each patient before the treatment.