title: Comparison of survival rates between patients treated with conventional radiotherapy and helical tomotherapy for head and neck cancer.
abstract: OBJECTIVE
  Compared to conventional radiotherapy (RT), intensity-modulated radiotherapy (IMRT) significantly reduces the rate of treatment-induced late toxicities in head and neck cancer. However, a clear survival benefit of IMRT over conventional RT has not yet been shown. This study is among the first comparative study to compare the survival rates between conventional RT and helical tomotherapy in head and neck cancer.
  
  
  METHODS
  From January 2008 to November 2011, 37 patients received conventional RT and 30 patients received helical tomotherapy for management of head and neck cancer. We retrospectively compared the survival rates between patients treated with conventional RT and helical tomotherapy, and analyzed the prognostic factors for survival.
  
  
  RESULTS
  The 1- and 2-year locoregional recurrence-free survival rates were 61.2% and 58.1% for the conventional RT group, 89.3% and 80.3% for the helical tomotherapy group, respectively. The locoregional recurrence-free survival rates of the helical tomotherapy group were significantly higher than conventional RT group (p = 0.029). There were no significant differences in the overall and distant metastasis-free survival between the two groups. RT technique, tumor stage, and RT duration were significant prognostic factors for locoregional recurrence-free survival.
  
  
  CONCLUSIONS
  This study showed the locoregional recurrence-free survival benefits of helical tomotherapy in the treatment of head and neck cancers.
authors.affiliation: Department of Radiation Oncology, Kyung Hee University School of Medicine, Seoul, Korea.
authors.forename: Moonkyoo
authors.initials: M
authors.lastname: Kong
authors.forename: Seong Eon
authors.initials: SE
authors.lastname: Hong
authors.forename: Jinhyun
authors.initials: J
authors.lastname: Choi
authors.forename: Youngkyong
authors.initials: Y
authors.lastname: Kim
keywords: Conventional radiotherapy; Head and neck cancer; Helical tomotherapy; Survival rate