Oesophageal IGRT considerations for SBRT of LA-NSCLC: barium-enhanced CBCT and interfraction motion.

Background: To determine the optimal volume of barium for oesophageal localisation on cone-beam CT (CBCT) for locally-advanced non-small cell lung cancers (NSCLC) and quantify the interfraction oesophageal movement relative to tumour.

Methods: Twenty NSCLC patients with mediastinal and/or hilar disease receiving radical radiotherapy were recruited. The first five patients received 25 ml of barium prior to their planning CT and alternate CBCTs during treatment.

Contrast enhanced oesophageal avoidance for stereotactic body radiotherapy: Barium vs. Gastrografin.

Introduction: SABR may facilitate treatment in a greater proportion of locally-advanced NSCLC patients, just as it has for early-stage disease. The oesophagus is one of the key dose-limiting organs and visualization during IGRT would better ensure toxicity is avoided. As the oesophagus is poorly seen on CBCT, we assessed the extent to which this is improved using two oral contrast agents.

Long-term treatment outcomes of patients with primary optic nerve sheath meningioma treated with stereotactic radiotherapy.

We analysed the long-term outcomes of patients with primary optic nerve sheath meningioma (ONSM) treated with stereotactic radiotherapy (SRT). 26 patients with primary ONSM were treated with SRT between 2004 and 2013 at a single institution. SRT was delivered with image guidance to a median dose of 50.

Fractionated Stereotactic Radiotherapy for Cavernous Venous Malformations of the Orbital Apex.

Purpose: The objective of this study was to investigate the efficacy and safety of fractionated stereotactic radiotherapy in the treatment of cavernous venous malformation of the orbital apex.

Methods: The authors reviewed a prospective database from a single center of patients with cavernous venous malformation of the orbital apex who had treatment with fractionated stereotactic radiotherapy. The authors compared the symptoms, visual function and the size of the tumor pre- and posttreatment as well as reviewed the treatment details and the incidence of complications.

Lung cancer radiation therapy in Australia and New Zealand: Patterns of practice.

Introduction: The RANZCR Faculty of Radiation Oncology Lung Interest Cooperative (FROLIC) surveyed patterns of lung cancer radiation therapy practice for non-small cell (NSCLC) and small cell lung cancer (SCLC) to evaluate current patterns of care and potential for improvement.

Methods: In October 2014, Radiation Oncologists (ROs) from all 62 departments in Australia and New Zealand were invited to a web-based survey directed at those treating lung cancer. Questions covered current radiation therapy practice as well as quality measures.

Limiting the risk of cardiac toxicity with esophageal-sparing intensity modulated radiotherapy for locally advanced lung cancers.

Background: Intensity modulated radiotherapy (IMRT) is routinely utilized in the treatment of locally advanced non-small cell lung cancer (NSCLC). RTOG 0617 found that overall survival was impacted by increased low (5 Gy) and intermediate (30 Gy) cardiac doses. We evaluated the impact of esophageal-sparing IMRT on cardiac doses with and without the heart considered in the planning process and predicted toxicity compared to 3D-conventional radiotherapy (3DCRT).

Multimodality guidance for accurate bronchoscopic insertion of fiducial markers.

Introduction: Fiducial markers act as visible surrogates of tumor position during image-guided radiotherapy. Marker placement has been attempted percutaneously but is associated with high rates of pneumothorax and chest drain placement.

Methods: Patients undergoing radical radiation treatment for non-small-cell lung cancer underwent bronchoscopic implantation of gold fiducials using radial probe endobronchial ultrasound (EBUS) with virtual bronchoscopy and fluoroscopic guidance to achieve tumor localization and placement within/adjacent to peripheral lung tumors.

Constituent components of out-of-field scatter dose for 18-MV intensity modulated radiation therapy versus 3-dimensional conformal radiation therapy: a comparison with 6-MV and implications for carcinogenesis.

Purpose: To characterize and compare the components of out-of-field dose for 18-MV intensity modulated radiation therapy (IMRT) versus 3-dimensional conformal radiation therapy (3D-CRT) and their 6-MV counterparts and consider implications for second cancer induction.

Methods And Materials: Comparable plans for each technique/energy were delivered to a water phantom with a sloping wall; under full scatter conditions; with field edge abutting but outside the bath to prevent internal/phantom scatter; and with shielding below the linear accelerator head to attenuate head leakage. Neutron measurements were obtained from published studies.

The efficacy of PET staging for small-cell lung cancer: a systematic review and cost analysis in the Australian setting.

Introduction: This study aimed to establish from the published literature the efficacy of a positron emission tomography (PET)-based strategy for the staging of small-cell lung cancer compared to conventional methods, the potential impact on patient management and outcomes, and cost implications for the Australian health system.

Methods: EMBASE, Current Contents, PubMed, and OVID, databases were searched using relevant search terms. Reference lists of identified studies were examined for additional pertinent papers.

A comparison of out-of-field dose and its constituent components for intensity-modulated radiation therapy versus conformal radiation therapy: implications for carcinogenesis.

Purpose: To investigate differences in scatter and leakage between 6-MV intensity-modulated radiation therapy (IMRT) and three-dimensional conformal radiation therapy (3DCRT); to describe the relative contributions of internal patient scatter, collimator scatter, and head leakage; and to discuss implications for second cancer induction.

Methods And Materials: Dose was measured at increasing distances from the field edge in a water bath with a sloping wall (1) under full scatter conditions, (2) with the field edge abutting but outside the bath to prevent internal (water) scatter, and (3) with the beam aperture plugged to reflect leakage only.

Results: Internal patient scatter from IMRT is 11% lower than 3DCRT, but collimator scatter and head leakage are five and three times higher, respectively.

Effect of intensity-modulated pelvic radiotherapy on second cancer risk in the postoperative treatment of endometrial and cervical cancer.

Purpose: To estimate and compare intensity-modulated radiotherapy (IMRT) with three-dimensional conformal radiotherapy (3DCRT) in terms of second cancer risk (SCR) for postoperative treatment of endometrial and cervical cancer.

Methods And Materials: To estimate SCR, the organ equivalent dose concept with a linear-exponential, a plateau, and a linear dose-response model was applied to dose distributions, calculated in a planning computed tomography scan of a 68-year-old woman. Three plans were computed: four-field 18-MV 3DCRT and nine-field IMRT with 6- and 18-MV photons.

The effect of intensity-modulated radiotherapy on radiation-induced second malignancies.

Purpose: To compare intensity-modulated radiotherapy (IMRT) with three-dimensional conformal radiotherapy (3D-CRT) in terms of carcinogenic risk for actual clinical scenarios.

Method And Materials: Clinically equivalent IMRT plans were generated for prostate, breast, and head-and-neck cases treated with 3D-CRT. Two possible dose-response models for radiocarcinogenesis were generated based on A-bomb survivor data corrected for fractionation.

Cerebral radiation necrosis: incidence, outcomes, and risk factors with emphasis on radiation parameters and chemotherapy.

Purpose: To investigate radiation necrosis in patients treated for glioma in terms of incidence, outcomes, predictive and prognostic factors.

Methods And Materials: Records were reviewed for 426 patients followed up until death or for at least 3 years. Logistic regression analysis was performed to identify predictive and prognostic factors.