Esophageal tolerance to high-dose stereotactic radiosurgery

Abstract

PurposeEsophageal tolerance is needed to guide the safe administration of stereotactic radiosurgery (SRS). We evaluated comprehensive dose-volume parameters of acute esophageal toxicity in patients with spinal metastasis treated with SRS.Materials and MethodsFrom May 2008 to May 2011, 30 cases in 27 patients with spinal metastasis received single fraction SRS to targets neighboring esophagus. Endpoints evaluated include length (mm), volume (mL), maximal dose (Gy), and series of dose-volume thresholds from the dose-volume histogram (volume of the organ treated beyond a threshold dose).ResultsThe median time from the start of irradiation to development of esophageal toxicity was 2 weeks (range, 1 to 12 weeks). Six events of grade 1 esophageal toxicity occurred. No grade 2 or higher events were observed. V15 of external surface of esophagus was found to predict acute esophageal toxicity revealed by multivariate analysis (odds radio = 1.272, p = 0.047).ConclusionIn patients with spinal metastasis who received SRS for palliation of symptoms, the threshold dose-volume parameter associated with acute esophageal toxicity was found to be V15 of external surface of esophagus. Restrict V15 to external surface of esophagus as low as possible might be safe and feasible in radiosurgery.

Dose-Volume Predictors of Esophagitis After Thoracic Stereotactic Body Radiation Therapy

“…In addition, toxicity studies after single-fraction spinal radiosurgery (SRS) may also be applicable to thoracic SBRT. [6][7][8] The purpose of this study was to examine the incidence and severity of esophagitis from stereotactic HFRT to central pulmonary lesions and to define esophageal dosimetric parameters that predict potentially dose-limiting toxicities, using a large single-institution database.…”