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Journal of Clinical Oncology : Official... Dec 2022Journal Journal of Clinical Oncology.The following case represents a relatively common clinical scenario of a postmenopausal female patient who presents with low-risk,... (Review)
Review
Journal Journal of Clinical Oncology.The following case represents a relatively common clinical scenario of a postmenopausal female patient who presents with low-risk, estrogen receptor-positive/progesterone receptor-positive/human epidermal growth factor receptor 2-negative, early-stage, left-sided breast cancer to discuss the role of postoperative radiation (RT) following wide local excision (WLE) and sentinel node biopsy. The spectrum of choices, ranging from omission of RT, accelerated partial breast irradiation (PBI), whole-breast radiation therapy, and the nuances of various dose/fractionation regimens for each option, are discussed in the context of the Danish Breast Cancer Study Group (DBCSG) PBI trial published in this issue, with additional review of other key trials that inform these treatment recommendations. After consideration of the clinical-pathologic features in the framework of the existing data and an in-depth discussion taking into consideration the patient's preferences/goals, the decision was made to deliver moderately hypofractionated RT (40 Gy/15 fractions) to a PBI volume, in concordance with the DBCSG-PBI trial.
Topics: Humans; Female; Breast Neoplasms; Breast; Radiation Dose Hypofractionation
PubMed: 36332170
DOI: 10.1200/JCO.22.01751 -
Journal of Neuro-oncology Oct 2021The outcomes of five fraction stereotactic radiotherapy (hfSRT) following brain metastasectomy were evaluated and compared with published series. (Review)
Review
PURPOSE
The outcomes of five fraction stereotactic radiotherapy (hfSRT) following brain metastasectomy were evaluated and compared with published series.
METHODS
30 Gy in 5 fractions HfSRT prescribed to the surgical cavity was reduced to 25 Gy if the volume of 'brain-GTV' receiving 20 Gy exceeded 20 cm. Endpoints were local recurrence, nodular leptomeningeal recurrence, new brain metastases and radionecrosis. The literature was searched for reports of clinical and dosimetric outcomes following postoperative hfSRT in 3-5 fractions.
RESULTS
39 patients with 40 surgical cavities were analyzed. Cavity local control rate at 1 year was 33/40 (82.5%). 3 local failures followed 30 Gy/5 fractions and 4 with 25 Gy/5 fractions. The incidence of leptomeningeal disease (LMD) was 7/40 (17.5%). No grade 3-4 toxicities, particularly no radionecrosis, were reported. The incidence of distant brain metastases was 15/40 (37.5%). The median overall survival was 15 months. Across 13 published series, the weighted mean local control was 83.1% (adjusted for sample size), the mean incidence of LMD was 14.9% (7-34%) and the mean rate of radionecrosis was 10.3% (0-20.6%).
CONCLUSION
Postoperative hfSRT can be delivered with 25-30 Gy in 5 fractions with efficacy in excess of 82% and no significant toxicity when the dose to 'brain-GTV' does not exceed 20 cm.
Topics: Brain; Brain Neoplasms; Humans; Meningeal Neoplasms; Metastasectomy; Radiation Dose Hypofractionation; Radiation Injuries; Radiosurgery; Retrospective Studies; Treatment Outcome
PubMed: 34546498
DOI: 10.1007/s11060-021-03840-5 -
Radiation Oncology (London, England) Feb 2023The main challenge in follow-up duration of patients with brain metastases after stereotactic radiotherapy is to distinguish between pseudo-progression and tumor...
BACKGROUND
The main challenge in follow-up duration of patients with brain metastases after stereotactic radiotherapy is to distinguish between pseudo-progression and tumor recurrence. The objective of this study is to retrospectively analyze the predictive factors.
METHODS
The study included 123 patients with enlarged brain metastases after hypo-fractionated radiotherapy in our center from March 2009 to October 2019, and the baseline clinical features, radiotherapy planning parameters, and enhanced magnetic resonance imaging before and after radiation therapy were analyzed. Logistic regression was performed to compare the differences between groups. Independent risk factors with P < 0.05 and associated with recurrence were used to establish a nomogram prediction model and validated by Bootstrap repeated sampling, which was validated in an internal cohort (n = 23) from October 2019 to December 2021.
RESULTS
The median follow-up time was 68.4 months (range, 8.9-146.2 months). A total of 76 (61.8%) patients were evaluated as pseudo-progression, 47 patients (38.2%) were evaluated as tumor recurrence. The median time to pseudo-progression and tumor recurrence were 18.3 months (quartile range, 9.4-27.8 months) and 12.9 months (quartile range, 8.7-19.6 months) respectively. Variables associated with tumor recurrence included: gross tumor volume ≥ 6 cc, biological effective dose < 60 Gy, target coverage < 96% and no targeted therapy. The area under curve values were 0.730 and 0.967 in the training and validation cohorts, respectively. Thirty-one patients received salvage therapy in the tumor recurrence group. The survival time in pseudo-progression and tumor recurrence groups were 66.3 months (95% CI 56.8-75.9 months) and 39.6 months (95% CI 29.2-50.0 months, respectively; P = 0.001).
CONCLUSIONS
Clinical and dosimetry features of hypo-fractionated radiation therapy based on enhanced brain magnetic resonance can help distinguish pseudo-progression from tumor recurrence after hypo-fractionated radiotherapy for brain metastases. Gross tumor volume, biological effective dose, target coverage, and having received targeted therapy or not were factors associated with the occurrence of tumor recurrence, and the individual risk could be estimated by the nomogram effectively.
Topics: Humans; Neoplasm Recurrence, Local; Retrospective Studies; Treatment Outcome; Brain Neoplasms; Radiosurgery; Dose Fractionation, Radiation
PubMed: 36788610
DOI: 10.1186/s13014-023-02214-7 -
International Journal of Radiation... Jun 2024In this Pediatric Normal Tissue Effects in the Clinic (PENTEC) vision paper, challenges and opportunities in the assessment of subsequent neoplasms (SNs) from radiation... (Review)
Review
PURPOSE
In this Pediatric Normal Tissue Effects in the Clinic (PENTEC) vision paper, challenges and opportunities in the assessment of subsequent neoplasms (SNs) from radiation therapy (RT) are presented and discussed in the context of technology advancement.
METHODS AND MATERIALS
The paper discusses the current knowledge of SN risks associated with historic, contemporary, and future RT technologies. Opportunities for research and SN mitigation strategies in pediatric patients with cancer are reviewed.
RESULTS
Present experience with radiation carcinogenesis is from populations exposed during widely different scenarios. Knowledge gaps exist within clinical cohorts and follow-up; dose-response and volume effects; dose-rate and fractionation effects; radiation quality and proton/particle therapy; age considerations; susceptibility of specific tissues; and risks related to genetic predisposition. The biological mechanisms associated with local and patient-level risks are largely unknown.
CONCLUSIONS
Future cancer care is expected to involve several available RT technologies, necessitating evidence and strategies to assess the performance of competing treatments. It is essential to maximize the utilization of existing follow-up while planning for prospective data collection, including standardized registration of individual treatment information with linkage across patient databases.
Topics: Humans; Child; Cancer Survivors; Neoplasms, Radiation-Induced; Organs at Risk; Proton Therapy; Neoplasms, Second Primary; Dose-Response Relationship, Radiation; Dose Fractionation, Radiation; Age Factors; Adolescent; Radiotherapy; Genetic Predisposition to Disease; Neoplasms
PubMed: 38430101
DOI: 10.1016/j.ijrobp.2024.01.206 -
Technology in Cancer Research &... 2020There are very few studies on noncoplanar radiation in tomotherapy because deformable image registration is not implemented in the TomoTherapy Planning Station, a...
BACKGROUND
There are very few studies on noncoplanar radiation in tomotherapy because deformable image registration is not implemented in the TomoTherapy Planning Station, a treatment planning device used in tomotherapy. This study examined whether noncoplanar radiation can be performed on the head using a tilt-type head and neck fixture and deformable image registration.
METHODS
Planning target volume spheres with diameters of 2, 3, and 4 cm were set on a head phantom, and computed tomography images were taken at 0° and 40° using a tilt-type head and neck fixture. Irradiation plans were created in the Tomotherapy Planning Station. Noncoplanar radiation was simulated, and the dose volume was evaluated by adding the 0° dose distribution and 40° dose distribution using the deformable image registration of the RayStation treatment planning system.
RESULTS
The ratio of the phantom volume to the irradiation dose for 20% to 30% of the planning target volume in noncoplanar radiation was smaller than that for 40% to 90% of the planning target volume in single-section irradiation at 0° or 40°.
CONCLUSIONS
Noncoplanar radiation on the head region using tomotherapy was possible by using a tilt-type head and neck fixture, and the dose distribution could be evaluated using deformable image registration. This method helps reduce the dose of the organ-at-risk region located slightly away from the planning target volume.
Topics: Brain Neoplasms; Dose Fractionation, Radiation; Humans; Phantoms, Imaging; Radiation Dosage; Radiosurgery; Radiotherapy Planning, Computer-Assisted; Radiotherapy, Image-Guided; Radiotherapy, Intensity-Modulated
PubMed: 32734825
DOI: 10.1177/1533033820945776 -
The British Journal of Radiology Aug 2020This study presents a methodology for voxel-based evaluation of two phase sequential radiotherapy treatment plans having conventional dose scheme in the first phase and...
OBJECTIVE
This study presents a methodology for voxel-based evaluation of two phase sequential radiotherapy treatment plans having conventional dose scheme in the first phase and subsequent hypofractionation dose scheme in the second phase based upon different priority [planning target volume (PTV), clinical target volume (CTV) and organs at risk (OAR)] of display modes.
METHODS
A case of carcinoma prostate was selected for demonstration. Varian Eclipse treatment planning system (TPS) was used for contouring and planning. In the first phase, a dose of 52 Gy in 26 fractions to the PTV and in the second phase, a dose of 19.5 Gy in 3 fractions to the PTV Boost was planned on the same CT data set. Both the plans (Phase 1 and Phase 2) were exported and processed using "Voxel-based radiobiology display (VRb) tool". Plan Sum for Biologically effective dose (BED)-Cube and equivalent dose of 2Gy (EQD)-Cube was reconstructed using a combination of linear quadratic (LQ) and linear quadratic-linear (LQ-L) radiobiological models. Tumor control probability (TCP) and normal tissue complication probability (NTCP) for different target volumes and organs were also calculated using EQD-volume histograms of the Plan Sum.
RESULTS
An in-house graphical user interface (GUI) is developed to present the qualitative and quantitative evaluation of the multiphase treatment plans with different display modes and dose regimens. The voxel based TCP obtained for the combined target volume was 90.56%. NTCP for the bladder and rectum was calculated from the Plan Sum histograms and found to be 0.33% and ~0.0% respectively.
CONCLUSION
The proposed methodology using the VRb tool offers superior plan evaluation for multiphase sequential radiotherapy treatment plans over the existing methods.
ADVANCES IN KNOWLEDGE
PTV, CTV and OAR priority based display modes in VRb tool offers better understanding of radiobiological evaluation of sequential radiotherapy treatment plans.
Topics: Dose Fractionation, Radiation; Humans; Male; Models, Statistical; Prostate; Prostatic Neoplasms; Radiotherapy Dosage; Radiotherapy Planning, Computer-Assisted
PubMed: 32614607
DOI: 10.1259/bjr.20200197 -
International Journal of Radiation... Feb 2022Multileaf collimator (MLC) linear accelerator (Linac)-based hypofractionated stereotactic radiation therapy (HSRT) is increasingly used not only for large brain...
PURPOSE
Multileaf collimator (MLC) linear accelerator (Linac)-based hypofractionated stereotactic radiation therapy (HSRT) is increasingly used not only for large brain metastases or those adjacent to critical structures but also for those metastases that would otherwise be considered for single-fraction radiosurgery (SRS). However, data on outcomes in general are limited, and there is a lack of understanding regarding optimal dosing. Our aim was to report mature image-based outcomes for MLC-Linac HSRT with a focus on clinical and dosimetric factors associated with local failure (LF).
METHODS AND MATERIALS
A total of 220 patients with 334 brain metastases treated with HSRT were identified. All patients were treated using a 5-fraction daily regimen and were followed with clinical evaluation and volumetric magnetic resonance imaging every 2 to 3 months. Overall survival and progression-free survival were calculated using the Kaplan-Meier method, with LF determined using Fine and Gray's competing risk method. Predictive factors were identified using Cox regression multivariate analysis.
RESULTS
Median follow-up was 10.8 months. Median size of treated metastasis was 1.9 cm; 60% of metastases were <2 cm in size. The median total dose was 30 Gy in 5 fractions; 36% of the cohort received <30 Gy. The median time to LF and 12-month cumulative incidence of LF was 8.5 months and 23.8%, respectively. Median time to death and 12-month overall survival rates were 11.8 months and 48.2%, respectively. Fifty-two metastases (15.6%) had an adverse radiation effect, of which 32 (9.5%) were symptomatic necrosis. Multivariable analysis identified worse LF in patients who received a total dose of <30 Gy (hazard ratio, 1.62; P = .03), with LF at 6 and 12 months of 13% and 33% for patients treated with <30 Gy versus 5% and 19% for patients treated with >30 Gy. Exploratory analysis demonstrated a dose-response effect observed in all histologic types, including among breast cancer subtypes.
CONCLUSION
Optimal local control is achieved with HSRT of ≥30 Gy in 5 daily fractions, independent of tumor volume and histology, with an acceptable risk of radiation necrosis.
Topics: Brain Neoplasms; Humans; Radiation Dose Hypofractionation; Radiosurgery; Retrospective Studies; Treatment Outcome
PubMed: 34537313
DOI: 10.1016/j.ijrobp.2021.09.003 -
Acta Oncologica (Stockholm, Sweden) Oct 2019The project aimed at determining the incidence of mandibular osteoradionecrosis (ORN) after radiotherapy, possible risk factors, and mandibular dose-volume effects in a...
The project aimed at determining the incidence of mandibular osteoradionecrosis (ORN) after radiotherapy, possible risk factors, and mandibular dose-volume effects in a large cohort of head and neck cancer patients (HNC). The cohort consisted of 1224 HNC patients treated with 66-68 Gy in 2007-2015 predominantly with IMRT. ORN cases were defined from clinical observations at follow-up and through hospital code diagnostics after oral-maxillofacial surgery and cross-checked with the national Danish Head and Neck Cancer database. In a nested case-control study, patients with ORN cases were matched with two controls (1:2) and pre-RT dental procedures including surgery to the mandible were documented. Multivariable Cox regression analysis was applied using demographic and treatment variables including dental procedures, smoking and tumor characteristics, and combined with dosimetric data. Mean mandibular dose () was pre-selected for the multivariable model. ORN was recorded in 56 cases (4.6%) with a median time to event of 10.9 months (range 1.8-89.7) after RT, 90% occurred within 37.4 months. Median follow-up time was 22 months (0.3-95). Average was significantly higher in the ORN event cohort and significant dose-volume differences were observed for population mean DVH doses between 30 Gy and 60 Gy. In univariable analysis, smoking (HR = 1.69; CI 1.14-2.5), pre-RT surgery/tooth extraction (HR = 2.76; 1.48-5.14), and several dosimetric parameters including (HR = 1.05, 1.02-1.08) were all significantly associated with ORN. and surgery/tooth extraction remained significant predictors of ORN in multivariable analysis, HR = 1.04 (CI 1.01-1.07) and HR = 2.09 (CI 1.1-3.98), respectively, while smoking only retained its significance in an interaction analysis with pre-RT dental procedures. The onset of ORN of the mandible was early (median 10.8 months) and the incidence low (4.6%) after IMRT in HNC cancer patients. Surgery to the mandible and pre-RT tooth extraction, tobacco smoking, and treatment dose were associated with the development of ORN.
Topics: Adult; Aged; Aged, 80 and over; Case-Control Studies; Dose Fractionation, Radiation; Dose-Response Relationship, Radiation; Female; Follow-Up Studies; Head and Neck Neoplasms; Humans; Incidence; Male; Mandible; Middle Aged; Neoplasm Staging; Oral Surgical Procedures; Osteoradionecrosis; Radiometry; Radiotherapy Dosage; Radiotherapy, Intensity-Modulated; Risk Factors; Tobacco Smoking
PubMed: 31364903
DOI: 10.1080/0284186X.2019.1643037 -
Cancer Medicine Jan 2021The external beam radiotherapy (EBRT) applied for prostate cancer (PCa) has been one of the most important and hottest research fields over recent decades. This study...
BACKGROUND
The external beam radiotherapy (EBRT) applied for prostate cancer (PCa) has been one of the most important and hottest research fields over recent decades. This study aimed to explore the research hotspots of EBRT in PCa and help the researchers have a clear and intuitive reference basis for later researches.
METHODS
The literature scientometric analysis related to "EBRT applied for PCa" was conducted via the Web of Science Core Collection from 2010 to 2019. The Microsoft Office Excel 2019 and CiteSpace V. 5.7.R1 software were introduced for visualizing and analyzing the data.
RESULTS
A total of 7860 relevant papers were extracted and downloaded. A total of 7828 papers were extracted and analyzed after data cleansing by CiteSpace. The tendency of published papers was comprehensively increasing from 2010 to 2019. Among all 73 countries/regions, USA published the most papers, accounting for 39%, which was the most active contributor with most publications. Australia (Centrality: 0.18), England (Centrality: 0.12) were cooperating most cohesively with other countries. Univ Toronto was the most productive institute (229), while Harvard Univ (Centrality: 0.67) had extensive collaborations with other institutes. The International journal of Radiation Oncology Biology Physics had the largest number of publications and the highest number of co-citations. Briganti A had the largest volume of publications. D'Amico AV had the highest number of co-citations. Four latest and largest clusters were identified as oligometastases, salvage therapy (SRT), prostate-specific membrane antigen (PSMA), and hypofractionation. Thirteen references became strongest burst citations lasting until 2019. The studies of "oligometastases," "SRT," "PSMA," "hypofractionation," "postoperative radiotherapy," and "dose and fraction regimen changes" were prevailing in the recent years.
CONCLUSION
The "oligometastases," "SRT," "PSMA," "hypofractionation," "postoperative radiotherapy," and "dose and fraction regimen changes" may be the state-of-art research frontiers, and related studies will advance in this field over time.
Topics: Bibliometrics; Biomedical Research; Humans; Knowledge Bases; Male; Prostatic Neoplasms; Publications; Radiation Dose Hypofractionation; Radiotherapy
PubMed: 33480190
DOI: 10.1002/cam4.3700 -
Environmental Monitoring and Assessment Jul 2022Antimony (Sb) is highly hazardous to human health even in minute concentration. Therefore, its accurate and precise determination in the real environmental samples is of...
Antimony (Sb) is highly hazardous to human health even in minute concentration. Therefore, its accurate and precise determination in the real environmental samples is of immense importance. In this work for the first time, UV-Vis spectrophotometric method was developed for the quantification of Sb(III) from water samples using supramolecular solvent (undecanol-tetrahydrofuran)-based extraction. The maximum absorption wavelength for antomony-diathizone complex was found to be 590 nm having molar absorptivity of 3.1 × 10 L.mol.cm. Factors affecting extraction efficiency like solution sample volume, amount of chelating agent, pH, matrix effect, and type and volume of supramolecular solvent were determined and optimized. Analytical parameters like limit of detection (0.19 µg L), limit of quantification (0.62 µg L), pre-concentration factor (15), enhancement factor (15), and relative standard deviation for 8 successive analysis (0.8%) were calculated under optimized experimental conditions. The method was applied to real water samples like tap water of laboratory, waste water from Kohat hospitals, and dam water (Tanda dam Kohat) with quantitative addition recovery (94-100%).
Topics: Antimony; Environmental Monitoring; Humans; Liquid Phase Microextraction; Liquid-Liquid Extraction; Solvents
PubMed: 35844019
DOI: 10.1007/s10661-022-10280-9