Dosimetric analysis of patients receiving volumetric-modulated arc palliative radiotherapy to the thoracic spine: A comparison with conventional mono-isocentric parallel opposed pair treatment.

Purpose: Volumetric modulated arc therapy (VMAT) has allowed for dose escalation and a decrease in radiation-induced toxicities for a variety of treatment sites, including spinal metastases. This article will compare the dosimetric impacts on normal lung tissue in patients treated with both VMAT and conventional treatment to the thoracic spine and determine if any significant difference exists among patient reported Edmonton Symptom Assessment System (ESAS) scores.

Methods: This retrospective quality assurance study identified 288 patients who received palliative radiotherapy to the thoracic spine using VMAT or conventional planning techniques with various palliative dose fractionation schemes.

Palliation of Vertebral Metastases with Radiotherapy: Exploration of Volumetric-Modulated Arc Therapy From Development to Implementation in Routine Clinical Practice.

The development of volumetric-modulated arc therapy (VMAT) in radiation therapy has allowed for improved dose escalation and a decrease in radiation-induced toxicities for patients. This article will describe a single centre's experience in development and implementation of VMAT for palliation of vertebral metastases. A retrospective planning analysis of 10 cases identified that utilization of VMAT decreases overall planning time with a statistically significant improvement in target coverage when compared with the current conventional technique.

Quality assurance of asymmetric jaw alignment using 2D diode array.

Purpose: A method using a 2D diode array is proposed to measure the junction gap (or overlap) and dose with high precision for routine quality assurance of the asymmetric jaw alignment.

Methods: The central axis (CAX) of the radiation field was determined with a 15 × 15 cm(2) photon field at four cardinal collimator angles so that the junction gap (or overlap) can be measured with respect to the CAX. Two abutting fields having a field size of 15 cm (length along the axis parallel to the junction) × 7.

Volumetric-modulated arc therapy for the treatment of a large planning target volume in thoracic esophageal cancer.

Recently, volumetric-modulated arc therapy (VMAT) has demonstrated the ability to deliver radiation dose precisely and accurately with a shorter delivery time compared to conventional intensity-modulated fixed-field treatment (IMRT). We applied the hypothesis of VMAT technique for the treatment of thoracic esophageal carcinoma to determine superior or equivalent conformal dose coverage for a large thoracic esophageal planning target volume (PTV) with superior or equivalent sparing of organs-at-risk (OARs) doses, and reduce delivery time and monitor units (MUs), in comparison with conventional fixed-field IMRT plans. We also analyzed and compared some other important metrics of treatment planning and treatment delivery for both IMRT and VMAT techniques.

Studies of the in vivo radiosensitivity of human skin fibroblasts.

Background And Purpose: To examine the radiosensitivity of skin cells obtained directly from the irradiated skin of patients undergoing fractionated radiation treatment prior to surgery for treatment of soft tissue sarcoma (STS) and to determine if there was a relationship with the development of wound healing complications associated with the surgery post-radiotherapy.

Methods: Micronucleus (MN) formation was measured in cells (primarily dermal fibroblasts) obtained from human skin at their first division after being removed from STS patients during post-radiotherapy surgery (2-9 weeks after the end of the radiotherapy). At the time of radiotherapy (planned tumor dose - 50Gy in 25 daily fractions) measurements were made of surface skin dose at predetermined marked sites.