title: Carbon ion beam radiotherapy for sinonasal malignant tumors invading skull base.
abstract: Objective. To evaluate the treatment outcome and prognostic factors in patients with sinonasal malignant tumors invading skull base. Study Design and Setting. A retrospective clinical study at the Yamagata University School of Medicine. Subjects and Methods. Three patients with sinonasal malignant tumors invading skull base were presented in present study. All patients were treated with carbon ion beam radiotherapy. The prescribed dose to the center of the clinical target volume was 64.0 GyE/16 fractions over 4 weeks at 4.0 GyE/fraction per day. Results. All patients completed carbon ion beam radiotherapy without an interval. The mean observation period was 39.6 months (range: 11-54 months). There were no local or regional recurrences in all cases; however, one patient had a metastasis in distant organs. Regarding the complications, visual loss was observed in one eye of one patient whose optic nerve was entirely involved by the tumor and field of carbon ion beam radiotherapy. Radiation induced brain injury was observed in two patients; however, these patients do not complain about neurological abnormality and had no treatment for radiation induced brain necrosis. Conclusions. Carbon ion beam radiotherapy for sinonasal malignant tumors invading the skull base showed therapeutic effectiveness.
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, Faculty of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan.
authors.forename: Nobuo
authors.initials: N
authors.lastname: Ohta
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, Faculty of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Suzuki
authors.affiliation: Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba 263-8555, Japan.
authors.forename: Azusa
authors.initials: A
authors.lastname: Hasegawa
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, Faculty of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan.
authors.forename: Masaru
authors.initials: M
authors.lastname: Aoyagi
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, Faculty of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan.
authors.forename: Seiji
authors.initials: S
authors.lastname: Kakehata