Carbon Ion Radiation Therapy for Unresectable Sacral Chordoma: An Analysis of 188 Cases

• Published in: International journal of radiation oncology, biology, physics Vol. 95; no. 1; pp. 322 - 327
• Main Authors: Imai, Reiko, MD, PhD, Kamada, Tadashi, MD, PhD, Araki, Nobuhito, MD, PhD
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-05-2016
• Subjects: Adult; Aged; Aged, 80 and over; Carbon - therapeutic use; CARBON IONS; Chordoma - mortality; Chordoma - pathology; Chordoma - radiotherapy; Female; Follow-Up Studies; GY RANGE; Heavy Ion Radiotherapy - adverse effects; Heavy Ion Radiotherapy - methods; Hematology, Oncology and Palliative Medicine; Humans; Male; Middle Aged; Neoplasm Recurrence, Local; NEOPLASMS; PATIENTS; Radiology; RADIOLOGY AND NUCLEAR MEDICINE; RADIOTHERAPY; Radiotherapy Dosage; Retrospective Studies; Sacrum; SI UNITS; Spinal Neoplasms - mortality; Spinal Neoplasms - pathology; Spinal Neoplasms - radiotherapy; Survival Rate; Time Factors; Tumor Burden; Walking
• ISSN: 0360-3016; 1879-355X
• DOI: 10.1016/j.ijrobp.2016.02.012

Purpose To evaluate the results of carbon ion radiation therapy administered to 188 patients with unresectable primary sacral chordomas. Patients and Methods One hundred eighty-eight patients were treated with carbon ion radiation therapy at a single institute between 1996 and 2013 and retrospectively analyzed. The median age was 66 years. The highest proximal invasion reached past S2 level in 137 patients. The median clinical target volume was 345 cm3 . One hundred six patients received 67.2 gray equivalents (GyE)/16 fractions (fr), 74 patients received 70.4 GyE/16 fr, 7 patients received 73.6 GyE/16 fr, and 1 patient received 64.0 GyE/16 fr. Results The median follow-up period was 62 months (range, 6.8-147.5 months). Seventy percent of patients were followed for 5 years or until death. The 5-year local control, overall survival, and disease-free survival rates were 77.2%, 81.1%, and 50.3%, respectively. Forty-one patients had a local recurrence. Sex, tumor volume, level of proximal invasion, and irradiated dose were unrelated to local control. There was grade 3 toxicity of the peripheral nerves in 6 patients and grade 4 toxicity of the skin in 2 patients. Ambulation remained in 97% of patients. Conclusions Carbon ion radiation therapy was safe and effective for unresectable chordoma and provided good local control and survival while preserving ambulation.