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Cancer Communications (London, England) Oct 2019Proton therapy offers dominant advantages over photon therapy due to the unique depth-dose characteristics of proton, which can cause a dramatic reduction in normal... (Review)
Review
Proton therapy offers dominant advantages over photon therapy due to the unique depth-dose characteristics of proton, which can cause a dramatic reduction in normal tissue doses both distal and proximal to the tumor target volume. In turn, this feature may allow dose escalation to the tumor target volume while sparing the tumor-neighboring susceptible organs at risk, which has the potential to reduce treatment toxicity and improve local control rate, quality of life and survival. Some dosimetric studies in various cancers have demonstrated the advantages over photon therapy in dose distributions. Further, it has been observed that proton therapy confers to substantial clinical advantage over photon therapy in head and neck, breast, hepatocellular, and non-small cell lung cancers. As such, proton therapy is regarded as the standard modality of radiotherapy in many pediatric cancers from the technical point of view. However, due to the limited clinical evidence, there have been concerns about the high cost of proton therapy from an economic point of view. Considering the treatment expenses for late radiation-induced toxicities, cost-effective analysis in many studies have shown that proton therapy is the most cost-effective option for brain, head and neck and selected breast cancers. Additional studies are warranted to better unveil the cost-effective values of proton therapy and to develop newer ways for better protection of normal tissues. This review aims at reviewing the recent studies on proton therapy to explore its benefits and cost-effectiveness in cancers. We strongly believe that proton therapy will be a common radiotherapy modality for most types of solid cancers in the future.
Topics: Cost-Benefit Analysis; Humans; Neoplasms; Proton Therapy
PubMed: 31640788
DOI: 10.1186/s40880-019-0407-3 -
The British Journal of Radiology Mar 2020It is recognized that the use of a single plan calculated on an image acquired some time before the treatment is generally insufficient to accurately represent the daily... (Review)
Review
It is recognized that the use of a single plan calculated on an image acquired some time before the treatment is generally insufficient to accurately represent the daily dose to the target and to the organs at risk. This is particularly true for protons, due to the physical finite range. Although this characteristic enables the generation of steep dose gradients, which is essential for highly conformal radiotherapy, it also tightens the dependency of the delivered dose to the range accuracy. In particular, the use of an outdated patient anatomy is one of the most significant sources of range inaccuracy, thus affecting the quality of the planned dose distribution. A plan should be ideally adapted as soon as anatomical variations occur, ideally online. In this review, we describe in detail the different steps of the adaptive workflow and discuss the challenges and corresponding state-of-the art developments in particular for an adaptive strategy.
Topics: Humans; Neoplasms; Organs at Risk; Photons; Proton Therapy; Radiotherapy Dosage; Radiotherapy Planning, Computer-Assisted; Radiotherapy, Conformal; Workflow
PubMed: 31647313
DOI: 10.1259/bjr.20190594 -
International Journal of Radiation... May 2016Radiation dose escalation has been shown to improve local control and survival in patients with non-small cell lung cancer in some studies, but randomized data have not... (Review)
Review
Radiation dose escalation has been shown to improve local control and survival in patients with non-small cell lung cancer in some studies, but randomized data have not supported this premise, possibly owing to adverse effects. Because of the physical characteristics of the Bragg peak, proton therapy (PT) delivers minimal exit dose distal to the target volume, resulting in better sparing of normal tissues in comparison to photon-based radiation therapy. This is particularly important for lung cancer given the proximity of the lung, heart, esophagus, major airways, large blood vessels, and spinal cord. However, PT is associated with more uncertainty because of the finite range of the proton beam and motion for thoracic cancers. PT is more costly than traditional photon therapy but may reduce side effects and toxicity-related hospitalization, which has its own associated cost. The cost of PT is decreasing over time because of reduced prices for the building, machine, maintenance, and overhead, as well as newer, shorter treatment programs. PT is improving rapidly as more research is performed particularly with the implementation of 4-dimensional computed tomography-based motion management and intensity modulated PT. Given these controversies, there is much debate in the oncology community about which patients with lung cancer benefit significantly from PT. The Particle Therapy Co-operative Group (PTCOG) Thoracic Subcommittee task group intends to address the issues of PT indications, advantages and limitations, cost-effectiveness, technology improvement, clinical trials, and future research directions. This consensus report can be used to guide clinical practice and indications for PT, insurance approval, and clinical or translational research directions.
Topics: Carcinoma, Non-Small-Cell Lung; Clinical Trials as Topic; Consensus; Humans; Lung Neoplasms; Movement; Organ Sparing Treatments; Organs at Risk; Proton Therapy; Radiation Injuries; Radiotherapy Planning, Computer-Assisted; Radiotherapy, Intensity-Modulated; Scattering, Radiation; Tumor Burden
PubMed: 27084663
DOI: 10.1016/j.ijrobp.2016.01.036 -
Radiotherapy and Oncology : Journal of... Jun 2022Inflammatory breast cancer (IBC) poses a radiotherapeutic challenge due to dermal lymphatic involvement, which often necessitates larger target volumes and chest wall...
PURPOSE
Inflammatory breast cancer (IBC) poses a radiotherapeutic challenge due to dermal lymphatic involvement, which often necessitates larger target volumes and chest wall boosts, making advanced planning techniques attractive to reduce exposure to nearby organs. We report our experience with intensity modulated proton therapy (IMPT) for the treatment of IBC.
METHODS
Between 2016 and 2020, all IBC patients treated with adjuvant IMPT at our institution were identified. Overall survival (OS) and distant metastasis-free survival (DMFS) were estimated using the Kaplan-Meier method. Adverse events (AEs) were assessed using CTCAE version 5.0.
RESULTS
Nineteen patients were identified with median 24-month follow-up. CTVs included skin, chest wall, and regional lymph nodes. Median dose was 50 Gy in 25 fractions, with fifteen receiving chest wall boost (median 56.25 Gy in 25 fractions). During treatment, plan re-optimization was required in 9 (47%). Acute grade 3 dermatitis occurred in 2 (11%). Rib facture occurred in 4 (21%). One patient with pre-existing surgical seroma experienced a grade 3 fistula. Mean heart, left anterior descending artery, and right coronary artery doses were 0.7 Gy, 2.3 Gy, and 0.1 Gy, respectively. Mean ipsilateral lung V20Gy was 14.9%. At 2 years, there were no locoregional recurrences, and OS and DMFS were 89% and 82%, respectively.
CONCLUSION
IMPT for IBC is well-tolerated with excellent dosimetry, low rates of AEs, and favorable early locoregional control outcomes. Follow-up for long-term outcomes is ongoing. Our findings suggest that IMPT is feasible and an attractive modality worthy of further investigation in patients with IBC.
Topics: Breast Neoplasms; Female; Humans; Inflammatory Breast Neoplasms; Neoplasm Recurrence, Local; Proton Therapy; Radiotherapy Dosage; Radiotherapy Planning, Computer-Assisted; Radiotherapy, Intensity-Modulated
PubMed: 35436537
DOI: 10.1016/j.radonc.2022.04.008 -
BMC Gastroenterology Aug 2023Hepatocellular carcinoma (HCC) with bile duct invasion (BDI) (BDIHCC) has a poor prognosis. Moreover, due to the paucity of reports, there is no consensus regarding...
AIM
Hepatocellular carcinoma (HCC) with bile duct invasion (BDI) (BDIHCC) has a poor prognosis. Moreover, due to the paucity of reports, there is no consensus regarding optimal management of this clinical condition yet. The aim of this study was to clarify the efficacy and safety of proton beam therapy (PBT) for BDIHCC.
METHODS
Between 2009 and 2018, 15 patients with BDIHCC underwent PBT at our institution. The overall survival (OS), local control (LC), and progression-free survival (PFS) curves were constructed using the Kaplan-Meier method. Toxicities were assessed using the Common Terminology Criteria of Adverse Events version 4.0.
RESULTS
The median follow-up time was 23.4 months (range, 7.9-54.3). The median age was 71 years (range, 58-90 years). Many patients were Child A (n = 8, 53.3%) and most had solitary tumors (n = 11, 73.3%). Additionally, most patients had central type BDI (n = 11, 73%). The median tumor size was 4.0 cm (range, 1.5-8.0 cm). The 1-, 2-, and 3-year OS rates were 80.0%, 58.7% and 40.2%, respectively, and the corresponding LC and PFS rates were 93.3%, 93.3%, and 74.7% and 72.7%, 9.7%, and 0.0%, respectively. Acute grade 1/2 dermatitis (n = 7, 46.7%), and grades 2 (n = 1, 6.7%) and 3 (n = 1, 6.7%) cholangitis were observed. Late toxicities such as grade 3 gastric hemorrhage and pleural effusion were observed. No toxicities of grade 4 or higher were observed.
CONCLUSIONS
PBT was feasible with tolerable toxicities for the treatment of BDIHCC.
Topics: Aged; Humans; Bile Ducts; Carcinoma, Hepatocellular; Liver Neoplasms; Progression-Free Survival; Proton Therapy; Middle Aged; Aged, 80 and over
PubMed: 37537527
DOI: 10.1186/s12876-023-02897-y -
International Journal of Urology :... Oct 2019Although prostate cancer control using radiotherapy is dose-dependent, dose-volume effects on late toxicities in organs at risk, such as the rectum and bladder, have... (Review)
Review
Although prostate cancer control using radiotherapy is dose-dependent, dose-volume effects on late toxicities in organs at risk, such as the rectum and bladder, have been observed. Both protons and carbon ions offer advantageous physical properties for radiotherapy, and create favorable dose distributions using fewer portals compared with photon-based radiotherapy. Thus, particle beam therapy using protons and carbon ions theoretically seems suitable for dose escalation and reduced risk of toxicity. However, it is difficult to evaluate the superiority of particle beam radiotherapy over photon beam radiotherapy for prostate cancer, as no clinical trials have directly compared the outcomes between the two types of therapy due to the limited number of facilities using particle beam therapy. The Japanese Society for Radiation Oncology organized a joint effort among research groups to establish standardized treatment policies and indications for particle beam therapy according to disease, and multicenter prospective studies have been planned for several common cancers. Clinical trials of proton beam therapy for intermediate-risk prostate cancer and carbon-ion therapy for high-risk prostate cancer have already begun. As particle beam therapy for prostate cancer is covered by the Japanese national health insurance system as of April 2018, and the number of facilities practicing particle beam therapy has increased recently, the number of prostate cancer patients treated with particle beam therapy in Japan is expected to increase drastically. Here, we review the results from studies of particle beam therapy for prostate cancer and discuss future developments in this field.
Topics: Disease-Free Survival; Humans; Male; Practice Guidelines as Topic; Prostate; Prostatic Neoplasms; Proton Therapy; Randomized Controlled Trials as Topic
PubMed: 31284326
DOI: 10.1111/iju.14041 -
Theranostics Sep 2013Proton therapy is very sensitive to uncertainties introduced during treatment planning and dose delivery. PET imaging of proton induced positron emitter distributions is... (Review)
Review
Proton therapy is very sensitive to uncertainties introduced during treatment planning and dose delivery. PET imaging of proton induced positron emitter distributions is the only practical approach for in vivo, in situ verification of proton therapy. This article reviews the current status of proton therapy verification with PET imaging. The different data detecting systems (in-beam, in-room and off-line PET), calculation methods for the prediction of proton induced PET activity distributions, and approaches for data evaluation are discussed.
Topics: Humans; Positron-Emission Tomography; Proton Therapy; Treatment Outcome
PubMed: 24312147
DOI: 10.7150/thno.5162 -
Physics in Medicine and Biology Oct 2022Dose delivery uncertainty is a major concern in proton therapy, adversely affecting the treatment precision and outcome. Recently, a promising technique, proton-acoustic...
Dose delivery uncertainty is a major concern in proton therapy, adversely affecting the treatment precision and outcome. Recently, a promising technique, proton-acoustic (PA) imaging, has been developed to provide real-time3D dose verification. However, its dosimetry accuracy is limited due to the limited-angle view of the ultrasound transducer. In this study, we developed a deep learning-based method to address the limited-view issue in the PA reconstruction. A deep cascaded convolutional neural network (DC-CNN) was proposed to reconstruct 3D high-quality radiation-induced pressures using PA signals detected by a matrix array, and then derive precise 3D dosimetry from pressures for dose verification in proton therapy. To validate its performance, we collected 81 prostate cancer patients' proton therapy treatment plans. Dose was calculated using the commercial software RayStation and was normalized to the maximum dose. The PA simulation was performed using the open-source k-wave package. A matrix ultrasound array with 64 × 64 sensors and 500 kHz central frequency was simulated near the perineum to acquire radiofrequency (RF) signals during dose delivery. For realistic acoustic simulations, tissue heterogeneity and attenuation were considered, and Gaussian white noise was added to the acquired RF signals. The proposed DC-CNN was trained on 204 samples from 69 patients and tested on 26 samples from 12 other patients. Predicted 3D pressures and dose maps were compared against the ground truth qualitatively and quantitatively using root-mean-squared-error (RMSE), gamma-index (GI), and dice coefficient of isodose lines. Results demonstrated that the proposed method considerably improved the limited-view PA image quality, reconstructing pressures with clear and accurate structures and deriving doses with a high agreement with the ground truth. Quantitatively, the pressure accuracy achieved an RMSE of 0.061, and the dose accuracy achieved an RMSE of 0.044, GI (3%/3 mm) of 93.71%, and 90%-isodose line dice of 0.922. The proposed method demonstrates the feasibility of achieving high-quality quantitative 3D dosimetry in PA imaging using a matrix array, which potentially enables the online 3D dose verification for prostate proton therapy.
Topics: Male; Humans; Proton Therapy; Protons; Prostate; Deep Learning; Acoustics; Phantoms, Imaging
PubMed: 36206745
DOI: 10.1088/1361-6560/ac9881 -
CNS Oncology Mar 2014Proton therapy is a novel technique for treating pediatric malignancies. As a tool to reduce normal-tissue dose, it has the potential to decrease late toxicity. Although... (Review)
Review
Proton therapy is a novel technique for treating pediatric malignancies. As a tool to reduce normal-tissue dose, it has the potential to decrease late toxicity. Although proton therapy has been used for over five decades, most pediatric dosimetry studies and clinical series have been published over the last 10 years. The purpose of this article is to review the physical, radiobiological and economic rationales for proton therapy in pediatric CNS malignancies, and provide an overview of the current challenges and future direction of research and utilization of this approach.
Topics: Animals; Central Nervous System Neoplasms; Child; Humans; Proton Therapy; Radiotherapy Planning, Computer-Assisted
PubMed: 25055020
DOI: 10.2217/cns.14.16 -
Journal of Medical Radiation Sciences Apr 2024The burden of cancer in Asia Pacific, a region home to over four billion people, is growing. Because of sheer demographics alone, the Asia Pacific region arguably has...
The burden of cancer in Asia Pacific, a region home to over four billion people, is growing. Because of sheer demographics alone, the Asia Pacific region arguably has the highest number of patients who can benefit from protons over conventional x-rays. However, only 39 out of 113 proton facilities globally are in Asia Pacific, and 11 of them are in low- and middle-income countries where 95% of the regional population reside. We draw attention to present resource distribution of proton therapy in Asia Pacific, highlight disparities in access, and suggest steps forward.
Topics: Humans; Proton Therapy; Asia; Neoplasms
PubMed: 38425125
DOI: 10.1002/jmrs.776