Clinical implementation of pencil beam scanning proton therapy for liver cancer with forced deep expiration breath hold.
CONCLUSION: We designed and clinically applied a technique for the treatment of liver cancer with proton pencil beam scanning in forced deep expiration breath-hold. The initial data on plan robustness and patient positioning suggest that the choices in terms of planning technique and treatment margins are able to reach the desired balance between target coverage and organ at risk sparing. PMID: 32976870 [PubMed - as supplied by publisher]
Proton pencil beam scanning (PBS) represents an interesting option for the treatment of breast cancer (BC) patients with nodal involvement. Here we compare tangential 3D-CRT and VMAT to PBS proton therapy (PT)...
Hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinomas (ICC) are the most prevalent intrahepatic primary cancer and the second leading cause of cancer death [Petrick2016], [Hong2016], [Igaki2017]. Although biologically and clinically distinct entities, both share common management issues.
CONCLUSION: Robustly optimized PBS-PT for cervical cancer patients shows equivalent target robustness against inter- and intra-fraction variability compared to VMAT, and offers significantly better OAR sparing. PMID: 32956707 [PubMed - as supplied by publisher]
Weber L, Høyer M Abstract The beneficial effects of protons are primarily based on reduction of low to intermediate radiation dose bath to normal tissue surrounding the radiotherapy target volume. Despite promise for reduced long-term toxicity, the percentage of cancer patients treated with proton therapy remains low. This is probably caused by technical improvements in planning and delivery of photon therapy, and by high cost, low availability and lack of high-level evidence on proton therapy. A number of proton treatment facilities are under construction or have recently opened; there are now two operatio...
CONCLUSION: The results of this study indicate that margin reduction below 3 mm/3% is possible but requires a larger cohort to substantiate clinical introduction. PMID: 32898561 [PubMed - as supplied by publisher]
We present the commissioning and quality assurance of our clinical protocol for respiratory gating in pencil beam scanning proton therapy for cancer patients with moving targets. In a novel approach, optical tracking has been integrated in the therapy workflow and used to monitor respiratory motion from multiple surrogates, applied on the patients' chest. The gating system was tested under a variety of experimental conditions, specific to proton therapy, to evaluate reaction time and reproducibility of dose delivery control. The system proved to be precise in the application of beam gating and allowed the mitigation of dos...
Compared to radiotherapy using photons, the superior beam properties of protons can be translated into two main strategies to obtain a clinical benefit: 1) dose escalation to improve local tumor control without increasing the risk of unacceptable radiation-induced toxicity, or 2) the sparing of healthy tissues with equivalent target dose to reduce the risk of radiation-induced side effects with similar tumor control. For the latter group of indications, the model-based approach was developed [1,2].
CONCLUSIONS: 4D dose reconstruction and accumulation enables the clinical estimation of actual exhibited interplay and motion effects. In the patients considered here, the loss of homogeneity caused by interplay and organ motion did not show systematic pattern and smeared out throughout the course of fractionated PBS-PT treatment. Dose degradation due to anatomical changes showed to be more severe and triggered treatment adaptations for five patients. PMID: 32768509 [PubMed - as supplied by publisher]
CONCLUSION: Model-based selection of patients with HNC for proton therapy is clinically feasible. Approximately one third of HNC patients qualify for protons and these patients have the highest probability to benefit from protons in terms of toxicity prevention. PMID: 32768508 [PubMed - as supplied by publisher]
This study demonstrated the feasibility of the proposed ultrasound-based motion modelling approach for its application in scanned proton therapy of lung tumours. PMID: 32721930 [PubMed - as supplied by publisher]