title: Reirradiation of spinal metastases with intensity-modulated radiation therapy: an analysis of 23 patients.
abstract: This study aimed to evaluate the efficacy and safety of reirradiation with intensity-modulated radiation therapy (IMRT) for spinal metastases. We retrospectively analyzed 23 patients with spinal metastases who underwent IMRT reirradiation between December 2006 and July 2013. We evaluated the spinal radiation doses during the first and second radiation therapy courses, the interval between the courses, and the clinical outcomes after reirradiation, including skeletal-related events, local control rates (LCRs), overall survival (OS), and toxicities. The median time from the first irradiation to reirradiation was 13 months (range, 2-75 months). The median reirradiation dose delivered to 90% of the planning target volume was 24.5 Gy in 5 fractions (range, 14.7-50 Gy in 3-25 fractions). Nineteen patients experienced pain at reirradiation, and 15 of these attained pain relief. Two of the three patients with paresis in the upper or lower extremities upon initiation of reirradiation demonstrated improvement. Local progression was identified in four patients. The median time to local progression was 37 months. The 1- and 2-year LCRs after reirradiation were 88% and 75%, respectively. The 1- and 2-year OS rates after reirradiation were 45% and 20%, respectively, with a median OS of 12 months. No late toxicities occurred. In conclusion, spinal metastasis reirradiation using IMRT appears safe; pain relief and paresis improvement and/or prevention can be expected, along with a reduced risk of radiation-induced toxicity, especially in the spinal cord.
authors.affiliation: Division of Radiation Oncology, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Shizuoka 411-8777, Japan Department of Radiation Oncology, Yamagata University Faculty of Medicine, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan shohei.kawashiro@gmail.com.
authors.forename: Shohei
authors.initials: S
authors.lastname: Kawashiro
authors.affiliation: Division of Radiation Oncology, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Shizuoka 411-8777, Japan.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Harada
authors.affiliation: Division of Orthopedic Oncology, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Shizuoka 411-8777, Japan.
authors.forename: Hirohisa
authors.initials: H
authors.lastname: Katagiri
authors.affiliation: Division of Radiation Oncology, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Shizuoka 411-8777, Japan.
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Asakura
authors.affiliation: Division of Radiation Oncology, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Shizuoka 411-8777, Japan.
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Ogawa
authors.affiliation: Division of Radiation Oncology, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Shizuoka 411-8777, Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Onoe
authors.affiliation: Division of Radiation Oncology, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Shizuoka 411-8777, Japan.
authors.forename: Kiyomi
authors.initials: K
authors.lastname: Sumita
authors.affiliation: Division of Proton Therapy, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Shizuoka 411-8777, Japan.
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Murayama
authors.affiliation: Division of Orthopedic Oncology, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Shizuoka 411-8777, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Murata
authors.affiliation: Department of Radiation Oncology, Yamagata University Faculty of Medicine, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Nemoto
authors.affiliation: Division of Orthopedic Oncology, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Shizuoka 411-8777, Japan.
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Takahashi
authors.affiliation: Division of Radiation Oncology, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Shizuoka 411-8777, Japan.
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Nishimura
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004307:Dose-Response Relationship, Radiation; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D050397:Radiotherapy, Intensity-Modulated; D012062:Relative Biological Effectiveness; D013125:Spinal Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy* / Q000556:secondary*; D014057:Tomography, X-Ray Computed; D017211:Treatment Failure
keywords: dose to the spinal cord; intensity-modulated radiation therapy; reirradiation; spinal metastasis