Robotic system-based fractionated stereotactic radiotherapy in locally recurrent nasopharyngeal carcinoma
Received 19 February 2009; received in revised form 16 September 2009; accepted 27 October 2009. published online 18 November 2009.
Abstract
Purpose
We reviewed survival, local control, and toxicity in patients with locally recurrent nasopharyngeal carcinoma (NPC) who had been treated with fractionated stereotactic radiotherapy (FSRT).
Materials and methods
Between June 2002 and March 2008, we retrospectively reviewed 35 patients with locally recurrent NPC treated using FSRT with CyberKnife. Gross tumor volumes ranged from 2.6 to 64.0ml (median, 7.9ml). Radiation doses were prescribed at the isodose line (75–84% of the maximum dose; median, 80%). The prescribed dose of FSRT ranged from 24 to 45Gy (median, 33Gy) in three or five fractions.
Results
The overall survival (OS) rate, local failure-free survival (LFFS) rate, and disease progression-free survival (DPFS) rate at 5years were 60%, 79%, and 74%, respectively. Twenty-three patients achieved complete response after FSRT. Only T stage at recurrence was an independent prognostic factor for OS and DPFS. Five patients exhibited severe late toxicity (Grade 4 or 5).
Conclusions
With regard to OS and LFFS, our study provided favorable outcomes. The incidence of severe late toxicities was acceptable in our study. FSRT would be considered as the alternative treatment of choice in re-irradiation for locally recurrent NPC.
aDepartment of Radiation Oncology, Korea Institute of Radiological & Medical Sciences, Republic of Korea
bCyberKnife Center, Korea Institute of Radiological & Medical Sciences, Republic of Korea
cDepartment of Otolaryngology-Head and Neck Surgery, Korea Institute of Radiological & Medical Sciences, Republic of Korea
Corresponding author. Address: Department of Radiation Oncology, Korea Cancer Center Hospital, Korea Institute of Radiological & Medical Sciences, 215-4 Gongneung-dong, Nowon-gu, Seoul 139-706, Republic of Korea.
ABSTRACT