Comparison of intensity modulated radiotherapy with simultaneous integrated boost (IMRT-SIB) and a 3-dimensional conformal parotid gland-sparing radiotherapy (ConPas 3D-CRT) in treatment of nasopharyngeal carcinoma: a mono-institutional experience
To compare intensity modulated radiotherapy with simultaneous integrated boost (IMRT-SIB) and a 3-dimensional conformal parotid gland-sparing radiotherapy (ConPas 3D-CRT) in treatment of nasopharyngeal carcinoma with regard to outcomes and dose distribution to the planning target volumes (PTVs) and to the organs at risk (OARs).
The treatment records of 24 patients with histologically proven carcinoma of the nasopharynx treated with ConPas 3D-CRT or IMRT-SIB technique between May 2009 and December 2016 were assessed.
The mean dose and dose to 50% parotid glands volume as well as the maximal dose to the spinal cord were significantly lower in the IMRT-SIB than in the ConPas 3-CRT group (p < 0.05; p < 0.05; p < 0.01, respectively). IMRT-SIB was also superior in coverage of PTVs. The 3-year overall survival (OS) and disease-free survival (DFS) of patients in the IMRT-SIB and ConPas 3D-CRT groups were 77 and 81% (p = 0.93), 51.9 and 70.7% (p = 0.83), respectively.
IMRT-SIB provided additional spearing to parotid glands and spinal cord in comparison to ConPas 3D-CRT technique but without improvement of OS and DFS.
KeywordsNasopharyngeal cancer Radiotherapy Treatment techniques Organs at risk
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
All procedure performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. The study was approved by the Ethics Committee of the University Hospital Zagreb.
Informed consent was obtained from all individual participants included in the study.
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