Simultaneous integrated boost intensity-modulated radiotherapy in esophageal carcinoma: early results of a phase II study.

Purpose: The safety and efficacy of using simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) for patients with esophageal squamous cell carcinoma were evaluated in a single-institution phase II setting.
Methods and Materials: Between June 2007 and October 2009, 45 patients underwent concurrent chemoradiotherapy (n = 27) or radiotherapy alone (n = 18). Two planning target volumes (PTV) were defined for the SIB: PTVC and PTVG, with prescribed doses of 50.4 Gy to the PTVC (1.8 Gy/fraction) and 63 Gy to the PTVG (2.25 Gy/fraction), both given in 28 fractions.
Results: At a median follow-up interval of 20.3 months, the 3-year overall survival (OS) and progression-free survival (PFS) rates were 42.2 and 40.7 %, respectively. The median overall survival time was 21 months; locoregional control rates were 83.3 % at 1 year and 67.5 % at 3 years. According to CTCAE (version 3.0) criteria, none of the patients developed grade 4-5 toxicity. The most common grade 2 and 3 radiation-related toxicity was radiation esophagitis, occurring in 64 % of all patients (but only 13 % as grade 3). No patient developed grade > 2 pulmonary complications.
Conclusion: SIB-IMRT is a feasible therapeutic approach for esophageal carcinoma patients and provides encouraging locoregional control with a low toxicity profile. Further investigations should focus on dose escalation and optimization of the combination with systemic therapies.