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1.
PurposeThis study aimed to determine the feasibility and maximally tolerated dose of hypofractionated, conformal radiation therapy (RT) in patients with liver metastases.Methods and materialsNonsurgical patients with ≤5 liver metastases (sum of maximal diameter of all lesions ≤8 cm) were included in the study. There were 4 dose levels: 35 Gy, 40 Gy (starting level), 45 Gy, and 50 Gy, in 10 fractions. The clinical target volume included metastases identified on contrast computed tomography or magnetic resonance imaging with a 5-mm margin within the liver. The planning target volume margin ranged from 4 to 30 mm, depending on breathing motion. Dose-limiting toxicities were defined as RT-related grade ≥4 hepatic or gastrointestinal toxicities or thrombocytopenia occurring within 90 days of the start of RT.ResultsA total of 26 patients with metastases from colorectal (8 patients), breast (7 patients) and other malignancies (11 patients) were enrolled between November 2005 and December 2010. Twenty-three patients were evaluable (8, 7, and 8 on the 40, 45, and 50 Gy dose levels, respectively). Two patients assigned to 50 Gy received 35 Gy owing to normal tissue limits, so 2 additional patients were treated to 50 Gy. There were no dose-limiting toxicities on any of the dose levels. On the 45 Gy dose level, 1 patient developed reversible grade 3 enteritis (37 days from RT start) and diarrhea (22 days); another patient developed grade 3 lymphopenia (23 days). At the 50 Gy dose level, 1 patient had grade 3 hyperglycemia (74 days), and another patient developed grade 3 lymphopenia (13 days), colonic hemorrhage (325 days), and colonic gastrointestinal obstruction (325 days). With a potential median follow-up of 66.1 months (range, 34.6-89.0 months), no other late toxicities were observed.ConclusionsTreatment of liver metastases with 50 Gy in 10 fractions was feasible and safe in a multi-institutional setting.  相似文献   

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PurposeTo report the 5-year outcomes from a single institution, prospective, phase 1/2 study on hypofractionated, accelerated radiation therapy to the prostate bed after radical prostatectomy.Methods and MaterialsPatients enrolled in this study were all eligible for postoperative radiation therapy and received a prescribed dose of 51 Gy in 17 fractions to the prostate bed. On follow-up, gastrointestinal (GI) and genitourinary (GU) toxicity was assessed using the National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0; prostate-specific antigen (PSA) was evaluated and quality of life was assessed using the Expanded Prostate Cancer Index Composite (EPIC) questionnaire.ResultsA total of 30 patients were enrolled between 2008 and 2011. Median age was 65 (52-75) years. Median pretreatment PSA was 0.12 ng/mL (0.01-1.42). Twenty-six (93%) patients had Gleason ≤7 disease, 13 (43%) had pT3 disease, and 20 (67%) had positive margins. Twenty-six patients (87%) underwent radiation therapy as salvage treatment. After a median follow-up of 6.4 (2.1-8.1) years, no patient experienced Common Terminology Criteria for Adverse Events grade 3/4 toxicity. Eleven patients (37%) had grade 2 genitourinary and 2 (7%) had grade 2 gastrointestinal toxicity. At baseline and 5 years after radiation therapy, mean EPIC urinary domain score was 80% (standard deviation, 18%) and 82% (17%). Mean EPIC bowel domain score was 93% (13%) and 93% (15%). One patient (4%) had a minimally clinically important change in urinary domain score and 1 patient (4%) had a minimally clinically important change in bowel domain score. Nelson-Aalen estimated cumulative incidence of biochemical failure was 31% (nadir +0.2) and 18% (nadir +2.0) at 5 years. Four-year PSA ≥0.4 was predictive of subsequent androgen deprivation therapy use (Nelson-Aalen cumulative incidence: 1.45; P < .0001). Five patients (17%) received hormonal therapy for biochemical failure. Nelson-Aalen estimated cumulative incidence of hormone therapy use was 14% at 5 years. All patients who received hormone therapy had PSA >0.4 at 4 years.ConclusionsIn this phase 1/2 study, hypofractionated postoperative radiation therapy seems to have good clinical efficacy without significant late toxicity. Phase 3 studies are warranted.  相似文献   

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Purpose

Limited data exist on testicular dose measurements using modern radiation treatment techniques and volumes for testicular seminoma. The aim of this study was to report the testicular dose using in vivo measurements in men with testicular seminoma receiving abdominopelvic radiation therapy (APRT) and a modified dog-leg field with and without gonadal shielding.

Methods and materials

Men with histologically confirmed testicular seminoma, either newly diagnosed stage II disease or isolated retroperitoneal relapse on surveillance for stage I disease, treated with APRT had testicular dose measurements recorded using MOSFET dosimeters. Those patients wishing to preserve fertility underwent radiation treatment with daily gonadal shielding. Factors that may influence testicular dose including field size, distance of the remaining testis from the radiation field, and patient separation, were also measured.

Results

Measurements were performed for 16 men; 10 with gonadal shielding and 6 without. The mean measured dose to the testis in the patients with gonadal shielding was 2.6 cGy (standard error, 0.75; range, 0-13) compared with 28.6 cGy (standard error, 12.6; range, 0-86) in the unshielded group for a 20-fraction treatment.

Conclusions

The use of gonadal shielding during APRT with a modified dog-leg technique results in a low testicular dose that is below the likely threshold for impaired spermatogenesis. In those men wishing to preserve fertility, we recommend the use of gonadal shielding, even with the use of modern radiation therapy techniques.  相似文献   

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Introduction

Economic analyses of upcoming treatments for lung cancer benefit from real-world health utility scores (HUSs) in an era of targeted therapy.

Methods

A longitudinal cohort study at Princess Margaret Cancer Centre evaluated 1571 EQ5D-3L-derived HUSs in 475 outpatients with metastatic lung cancer across various disease states. Patients with epidermal growth factor receptor (EGFR) (n = 183) and anaplastic lymphoma kinase (ALK) (n = 38) driver alterations were enriched through targeted enrolment; patients with wild-type non–small-cell lung cancer (WT NSCLC) (n = 224) and small-cell lung cancer (SCLC) (n = 30) were sampled randomly.

Results

For patients stable on most appropriate treatment, the mean HUSs were 0.81 and 0.82 in patients receiving EGFR and ALK tyrosine kinase inhibitors (TKIs) respectively (with similar HUSs across agents), which were higher than patients with WT NSCLC (0.78; P = .04) and SCLC receiving chemotherapy (0.72; P = .06). In mutation-specific comparisons, disease stability on appropriate therapy resulted in significantly higher mean HUSs (P < .002-.02) than when disease was progressing (mean HUS: EGFR, 0.70; ALK, 0.69; WT NSCLC, 0.66; SCLC, 0.52). When evaluating treatment-related toxicities, significant inverse relationships were observed between HUS and the severity of fatigue and decreased appetite in the EGFR group. There was also a significant inverse relationship between the total number of clinically significant symptoms and HUS, both in patients who were EGFR-mutated and patients with WT NSCLC.

Conclusions

In a North American setting, HUSs generated from patients with metastatic lung cancer are higher in treated, stable patients carrying driver mutations. This is partially explainable by treatment toxicity and patient symptom differences. Such differences in scores should be considered in economic analyses.  相似文献   

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IntroductionThe relationships between morbid obesity, changes in body mass index (BMI) before cancer diagnosis, and lung cancer outcomes by histology (SCLC and NSCLC) have not been well studied.MethodsIndividual level data analysis was performed on 25,430 patients with NSCLC and 2787 patients with SCLC from 16 studies of the International Lung Cancer Consortium evaluating the association between various BMI variables and lung cancer overall survival, reported as adjusted hazard ratios (aHRs) from Cox proportional hazards models and adjusted penalized smoothing spline plots.ResultsOverall survival of NSCLC had putative U-shaped hazard ratio relationships with BMI based on spline plots: being underweight (BMI < 18.5 kg/m2; aHR = 1.56; 95% confidence interval [CI]:1.43–1.70) or morbidly overweight (BMI > 40 kg/m2; aHR = 1.09; 95% CI: 0.95–1.26) at the time of diagnosis was associated with worse stage-specific prognosis, whereas being overweight (25 kg/m2 ≤ BMI < 30 kg/m2; aHR = 0.89; 95% CI: 0.85–0.95) or obese (30 kg/m2 ≤ BMI ≤ 40 kg/m2; aHR = 0.86; 95% CI: 0.82–0.91) was associated with improved survival. Although not significant, a similar pattern was seen with SCLC. Compared with an increased or stable BMI from the period between young adulthood until date of diagnosis, a decreased BMI was associated with worse outcomes in NSCLC (aHR = 1.24; 95% CI: 1.2–1.3) and SCLC patients (aHR=1.26 (95% CI: 1.0–1.6). Decreased BMI was consistently associated with worse outcome, across clinicodemographic subsets.ConclusionsBoth being underweight or morbidly obese at time of diagnosis is associated with lower stage-specific survival in independent assessments of NSCLC and SCLC patients. In addition, a decrease in BMI at lung cancer diagnosis relative to early adulthood is a consistent marker of poor survival.  相似文献   

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A diet deficient in choline and methionine, known to produce hepatocellular carcinoma in the absence of any added chemical carcinogen, induced lipid peroxidation in the nuclear fraction of the liver when fed to male Fischer 344 rats. This lipid peroxidation was detected within 1 day of feeding the diet by the appearance of diene conjugates and increased progressively up to 3 days. It was prevented completely by the addition of choline chloride to the diet. The close proximity of DNA may make it a possible target for attack by free radicals.  相似文献   

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Purpose

Emergent palliative radiation therapy (PRT) of symptomatic metastases can significantly increase the quality of life of patients with cancer. In some contexts, this treatment may be underused, but in others PRT may represent an excessively aggressive intervention. The characterization of the current use of emergent PRT is warranted for optimized value and patient-centered care.

Methods and Materials

This study is a cross-sectional retrospective analysis of all emergent PRT courses at a single academic tertiary institution across 1 year.

Results

A total of 214 patients received a total of 238 treatment courses. The most common indications were bone (39%) and brain (14%) metastases. Compared with outpatients, inpatients had lower mean survival rates (2 months vs 6 months; P < .001), higher rates of stopping treatment early (19.1% vs 9.0%; P = .034), and greater involvement of palliative care (44.8% vs 24.1%; P < .001), but the same mean planned fractions (9.10 vs 9.40 fractions; P = .669). In a multiple predictor survival analysis, palliative care involvement (P = .025), male sex (P = .001), ending treatment early (P = .011), and having 1 of 3 serious indications (airway compromise, leptomeningeal disease, and superior/inferior vena cava involvement; P = .007) were significantly associated with worse overall survival.

Conclusions

Survival is particularly poor in patients who receive emergent PRT, and patient characteristics such as functional status and indication should be considered when determining fractionation schedule and dosing. A multi-institutional study of practice patterns and outcomes is warranted.  相似文献   

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Purpose

As radiation therapy treatment grows more complex over time, treatment delivery has become more susceptible to adverse events and patient safety risks from use error. The radiation therapy monitoring and treatment delivery user interface explored in this study was redesigned using ecological interface design, a human factors engineering method, and evaluated to improve treatment safety.

Methods and materials

An initial design concept was created based on previously completed analysis and informally evaluated in focus groups with radiation therapists. Sixteen newly graduated radiation therapists used both the redesigned and current system in a usability test to determine if the redesigned system better supported detection of errors.

Results

The redesigned system successfully improved the error detection rate of 2 errors: wrong treatment volume and wrong treatment site (P < .03 and P < .01, respectively). It also improved level 2 and level 3 situation awareness (ie, comprehension of the meaning of the information and the projection of the behavior of the technology: P < .01 and P < .01, respectively) and achieved a higher user satisfaction.

Conclusions

The ecological interface design approach was found to be effective in redesigning a radiation therapy treatment delivery interface. Radiation therapists were able to deliver simulated radiation therapy with a higher rate of error detection and improved higher-level situation awareness, and participants preferred the redesigned interface to the current interface. Overall, the redesigned interface improved the radiation therapists’ system understanding and ability to detect errors that affect patient safety.  相似文献   

15.
IntroductionFinancial distress has been established as a clinically relevant patient-reported outcome associated with worse mortality and quality of life. Our goal was to define factors associated with financial burden (FB) in a public health care system.Materials and MethodsPatients with advanced lung cancer were recruited from outpatient clinics at the Princess Margaret Cancer Centre (Toronto, Canada). FB was measured with the validated Comprehensive Score for Financial Toxicity (COST) instrument, a 12-item survey scored from 0 to 44, with lower scores reflecting worse financial well-being. Data on patient and treatment characteristics, total out-of-pocket costs (OOP), and private insurance coverage were collected. Multivariable logistic regression models were fit for COST score and each variable, to determine factors associated with greater FB (COST < 21).ResultsOf 251 patients approached, 200 (80%) participated. The median age of the cohort was 65 years; 56% were female. The median total OOP ranged between $1000 and $5000 CAD. The median COST score was 21 (range, 0-44). FB was associated with age, with patients < 65 years reporting greater FB than older patients (COST, 18.0 vs. 24.0; P < .0001). In multivariable logistic regression analysis, younger age was associated with greater FB, when adjusting for income, employment status, OOP, and private insurance coverage (odds ratio, 3.6; 95% confidence interval, 1.5-9.1; P < .0001).ConclusionAge is significantly associated with FB in the Canadian (Ontario) public health care system, with younger patients with lung cancer reporting greater financial distress. This study highlights priority patient populations where FB should be routinely assessed and appropriate resources for support offered.  相似文献   

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Purpose

Magnetic resonance imaging guided (MRI-g) radiation therapy provides visualization of the target and organs at risk (OARs), allowing for daily online adaptive radiation therapy (OART). We hypothesized that MRI-g OART would improve OAR sparing and target coverage in patients with pancreatic cancer treated with stereotactic body radiation therapy (SBRT).

Methods and Materials

Ten patients received pancreas SBRT to a dose of 33 to 40 Gy in 5 fractions. The dose was prescribed to 90% coverage of the planning target volume at 100% isodose (PTV100). After each fraction's setup magnetic resonance imaging scan, the target position was aligned by 3-dimensional shifts, the normal anatomy was recontoured, and the original radiation therapy plan was recalculated to create a nonadaptive plan. A reoptimized (adaptive) plan was then generated for each fraction and renormalized to 90% coverage of PTV100. Target and OAR doses between nonadaptive and adaptive plans were compared to assess the dosimetric impact of daily adaptation.

Results

The PTV100 mean for adaptive and nonadaptive techniques was 90% and 80.4% (range, 46%-97%), respectively (P = .0008). Point maximum (Dmax) 38 Gy duodenum objectives were met in 43 adaptive fractions compared with 32 nonadaptive fractions (P = .022). Both PTV100 ≥90% and all OAR objectives were achieved in 28 adaptive fractions compared with only 3 nonadaptive fractions. For nonadaptive plans, interfraction increases in stomach volume correlated with higher stomach V33 (P = .004), stomach Dmax (P = .009), duodenum V33 (P = .021), and duodenum Dmax (P = .105). No correlation was observed between stomach volume and OAR doses for adaptive plans. OART plans with Dmax violations of the spinal cord (20 Gy) in 4 fractions and large bowel (38 Gy) in 5 fractions were identified (although not delivered).

Conclusions

MRI-g OART improves target coverage and OAR sparing for pancreas SBRT. This benefit partially results from mitigation of interfraction variability in stomach volume. Caution must be exercised to evaluate all OARs near the treatment area.  相似文献   

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Purpose

This patient study evaluated the use of 3-dimensional (3D) printed bolus for chest wall radiation therapy compared with standard sheet bolus with regard to accuracy of fit, surface dose measured in vivo, and efficiency of patient setup. By alternating bolus type over the course of therapy, each patient served as her own control.

Methods and materials

For 16 patients undergoing chest wall radiation therapy, a custom 5.0 mm thick bolus was designed based on the treatment planning computed tomography scan and 3D printed using polylactic acid. Cone beam computed tomography scanning was used to image and quantify the accuracy of fit of the 2 bolus types with regard to air gaps between the bolus and skin. As a quality assurance measure for the 3D printed bolus, optically stimulated luminescent dosimetry provided in vivo comparison of surface dose at 7 points on the chest wall. Durations of patient setup and image guidance were recorded and compared.

Results

In 13 of 16 patients, the bolus was printed without user intervention, and the median print time was 12.6 hours. The accuracy of fit of the bolus to the chest wall was improved significantly relative to standard sheet bolus, with the frequency of air gaps 5 mm or greater reduced from 30% to 13% (P < .001) and maximum air gap dimension diminished from 0.5 ± 0.3 to 0.3 ± 0.3 mm on average. Surface dose was within 3% for both standard sheet and 3D printed bolus. On average, the use of 3D printed bolus reduced the setup time from 104 to 76 seconds.

Conclusions

This study demonstrates 3D printed bolus in postmastectomy radiation therapy improves fit of the bolus and reduces patient setup time marginally compared with standard vinyl gel sheet bolus. The time savings on patient setup must be weighed against the considerable time needed for the 3D printing process.  相似文献   

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Purpose

To compare lung tumor motion measured with a model-based technique to commercial 4-dimensional computed tomography (4DCT) scans and describe a workflow for using model-based 4DCT as a clinical simulation protocol.

Methods and materials

Twenty patients were imaged using a model-based technique and commercial 4DCT. Tumor motion was measured on each commercial 4DCT dataset and was calculated on model-based datasets for 3 breathing amplitude percentile intervals: 5th to 85th, 5th to 95th, and 0th to 100th. Internal target volumes (ITVs) were defined on the 4DCT and 5th to 85th interval datasets and compared using Dice similarity. Images were evaluated for noise and rated by 2 radiation oncologists for artifacts.

Results

Mean differences in tumor motion magnitude between commercial and model-based images were 0.47 ± 3.0, 1.63 ± 3.17, and 5.16 ± 4.90 mm for the 5th to 85th, 5th to 95th, and 0th to 100th amplitude intervals, respectively. Dice coefficients between ITVs defined on commercial and 5th to 85th model-based images had a mean value of 0.77 ± 0.09. Single standard deviation image noise was 11.6 ± 9.6 HU in the liver and 6.8 ± 4.7 HU in the aorta for the model-based images compared with 57.7 ± 30 and 33.7 ± 15.4 for commercial 4DCT. Mean model error within the ITV regions was 1.71 ± 0.81 mm. Model-based images exhibited reduced presence of artifacts at the tumor compared with commercial images.

Conclusion

Tumor motion measured with the model-based technique using the 5th to 85th percentile breathing amplitude interval corresponded more closely to commercial 4DCT than the 5th to 95th or 0th to 100th intervals, which showed greater motion on average. The model-based technique tended to display increased tumor motion when breathing amplitude intervals wider than 5th to 85th were used because of the influence of unusually deep inhalations. These results suggest that care must be taken in selecting the appropriate interval during image generation when using model-based 4DCT methods.  相似文献   

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