Journal of radiosurgery and SBRT最新文献

Our randomized clinical study comparing stereotactic body radiotherapy (SBRT) and stereotactic body proton therapy (SBPT) for early stage non-small cell lung cancer (NSCLC) was closed prematurely owing to poor enrollment, largely because of lack of volumetric imaging and difficulty in obtaining insurance coverage for the SBPT group. In this article, we describe technology improvements in our new proton therapy center, particularly in image guidance with cone beam CT (CBCT) and CT on rail (CTOR), as well as motion management with real-time gated proton therapy (RGPT) and optical surface imaging. In addition, we have a treatment planning system that provides better treatment plan optimization and more accurate dose calculation. We expect to re-start the SBPT program, including for early stage NSCLC as well as for other disease sites soon after starting patient treatment at our new proton therapy center.

Stereotactic body radiotherapy (SBRT) is well accepted for low- and intermediate-favorable risk prostate cancer. Available evidence about the application of SBRT in unfavorable- and high-risk prostate cancer is less solid. During last year's multiple variations in treatment, techniques have been reported making comparisons more complicated. This review's objective is to review current evidence in application of SBRT in intermediate unfavourable and high-risk prostate cancer and to outline variations in SBRT treatment techniques and relevant results.

This study investigated if field output correction factors (FOCFs) of Varian stereotactic cones for Edge detectorTM had dependence on cone size, measurement setup, reference field size and/or photon energy. Field output factors (FOFs) of stereotactic cones were measured at three depths (1.5 cm, 5 cm and 10 cm) in two different setups (source-to-surface distance (SSD) and source-to-axis distance (SAD)) with two photon energies (6 MV and 6 MV flattening filter free) using the Edge detector and Exradin_® W2 scintillator. Two reference fields (10 × 10 cm² and 4 × 4 cm²) were chosen. FOCFs for the Edge detector were determined by calculating FOF_W2/FOF_Edge and compared among cones and between depths, setups, reference fields and energies. It is concluded that FOCFs for the Edge detector have dependence on cone size, SSD/SAD setup and energy for small cones, but do not have dependence on depth and reference field size.

Jugulotympanic paraganglioma (JTPG), a benign slow-growing neoplasm in the skull base with a tendency to be locally invasive, poses a treatment challenge because of its proximity to nearby neurovascular structures. The authors describe 11 patents with 12 Fisch-classified JTPGs treated with GammaKnife radiosurgery (GKRS) during a 12-year period. The observed rates of subjective improvement and tumor control were 80% and 83%, respectively. Among the individuals living longer than 5 years, tumor growth developed at 77 and 180 months after radiosurgery in two patients. Treatment-related toxicity or radiation oncogenesis was not observed. GKRS seems to be a valid treatment option for all Fisch designated skull base glomus tumors. Life-long follow-up of these patients is necessary.

Objectives: To perform a systematic review and meta-analysis of outcomes for patients with locally recurrent brain metastases treated with a repeat course of stereotactic radiosurgery (rSRS).

Method: Primary outcomes were 1-year local control(LC) and radionecrosis (RN). Secondary outcomes were 1-year overall survival (OS) and 1-year distant brain control (DBC). Weighted random effects meta-analyses utilizing the DerSimonian and Laird methods were conducted to characterize summary effect sizes. Mixed effects regression models were utilized to analyze potential correlations between prognostic factors and outcomes.

Results: In total, 347 patients with 462 brain metastases treated with rSRS were included. Estimated 1-year LC, OS, and DBC rates were 69.0% (95% CI: 61.0-77.0%), 49.7% (95% CI: 28.9-70.6%), and 41.6% (95% CI: 33.0-50.4%), respectively. The estimated RN rate was 16.1% (95% CI: 6.3-25.9%). Every 1 Gy increase in prescription dose was estimated to result in roughly 5% increase in 1-year LC (p = 0.14).

Conclusions: rSRS was well-tolerated with reasonable 1-year LC and OS. Dose escalation may result in improved LC.