Open AccessProton beam therapy for bone sarcomas of the skull base and spine: A retrospective nationwide multicenter study in Japan
Author(s) -
Demizu Yusuke,
Mizumoto Masashi,
Onoe Tsuyoshi,
Nakamura Naoki,
Kikuchi Yasuhiro,
Shibata Tetsushi,
Okimoto Tomoaki,
Sakurai Hideyuki,
Akimoto Tetsuo,
Ono Kota,
Daimon Takashi,
Murayama Shigeyuki
Publication year - 2017
Publication title -
cancer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.035
H-Index - 141
eISSN - 1349-7006
pISSN - 1347-9032
DOI - 10.1111/cas.13192
Subject(s) - medicine , chordoma , chondrosarcoma , skull , retrospective cohort study , surgery , osteosarcoma , radiation therapy , sarcoma , pathology
We conducted a retrospective, nationwide multicenter study to evaluate the clinical outcomes of proton beam therapy for bone sarcomas of the skull base and spine in Japan. Eligibility criteria included: (i) histologically proven bone sarcomas of the skull base or spine; (ii) no metastases; (iii) ≥20 years of age; and (iv) no prior treatment with radiotherapy. Of the 103 patients treated between January 2004 and January 2012, we retrospectively analyzed data from 96 patients who were followed‐up for >6 months or had died within 6 months. Seventy‐two patients (75.0%) had chordoma, 20 patients (20.8%) had chondrosarcoma, and four patients (7.2%) had osteosarcoma. The most frequent tumor locations included the skull base in 68 patients (70.8%) and the sacral spine in 13 patients (13.5%). Patients received a median total dose of 70.0 Gy (relative biological effectiveness). The median follow‐up was 52.6 (range, 6.3–131.9) months. The 5‐year overall survival, progression‐free survival, and local control rates were 75.3%, 49.6%, and 71.1%, respectively. Performance status was a significant factor for overall survival and progression‐free survival, whilst sex was a significant factor for local control. Acute Grade 3 and late toxicities of ≥Grade 3 were observed in nine patients (9.4%) each (late Grade 4 toxicities [ n = 3 patients; 3.1%]). No treatment‐related deaths occurred. Proton beam therapy is safe and effective for the treatment of bone sarcomas of the skull base and spine in Japan. However, larger prospective studies with a longer follow‐up are warranted.