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1.
J Nucl Med Technol ; 51(2): 133-139, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37192822

ABSTRACT

Our purpose was to investigate the utility of 18F-FDG PET/MRI and serial blood work to detect early inflammatory responses and cardiac functionality changes at 1 mo after radiation therapy (RT) in patients with left-sided breast cancer. Methods: Fifteen left-sided breast cancer patients who enrolled in the RICT-BREAST study underwent cardiac PET/MRI at baseline and 1 mo after standard RT. Eleven patients received deep-inspiration breath-hold RT, whereas the others received free-breathing RT. A list-mode 18F-FDG PET scan with glucose suppression was acquired. Myocardial inflammation was quantified by the change in 18F-FDG SUVmean (based on body weight) and analyzed on the basis of the myocardial tissue associated with the left anterior descending, left circumflex, or right coronary artery territories. MRI assessments, including left ventricular functional and extracellular volumes (ECVs), were extracted from T1 (before and during a constant infusion of gadolinium) and cine images, respectively, acquired simultaneously during the PET acquisition. Cardiac injury and inflammation biomarker measurements of high-sensitivity troponin T, high-sensitivity C-reactive protein, and erythrocyte sedimentation rate were measured at the 1-mo follow-up and compared with preirradiation values. Results: At the 1-mo follow-up, a significant increase (10%) in myocardial SUVmean in left anterior descending segments (P = 0.04) and ECVs in slices at the apex (6%) and base (5%) was detected (P ≤ 0.02). Further, a significant reduction in left ventricular stroke volume (-7%) was seen (P < 0.02). No significant changes in any circulating biomarkers were seen at follow-up. Conclusion: Myocardial 18F-FDG uptake and functional MRI, including stroke volume and ECVs, were sensitive to changes at 1 mo after breast cancer RT, with findings suggesting an acute cardiac inflammatory response to RT.


Subject(s)
Breast Neoplasms , Unilateral Breast Neoplasms , Humans , Female , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/radiotherapy , Fluorodeoxyglucose F18 , Heart/diagnostic imaging , Positron-Emission Tomography , Arrhythmias, Cardiac , Magnetic Resonance Imaging
2.
BMC Palliat Care ; 21(1): 220, 2022 Dec 09.
Article in English | MEDLINE | ID: mdl-36482335

ABSTRACT

BACKGROUND: Palliative radiotherapy (PRT) is an effective treatment for managing symptoms of advanced cancer. At least half of all radiation treatments are delivered with palliative intent, aimed at relieving symptoms, such as pain or shortness of breath. Symptomatic patients must receive PRT quickly, therefore expeditious treatment planning is essential. Standard radiation planning requires a dedicated CT scan acquired at the cancer centre, called a 'CT simulation', which facilitates treatment planning (i.e. tumor delineation, placement of radiation beams and dose calculation). However, the CT simulation process creates a bottleneck and often leads to delays in starting treatment. Other researchers have indicated that CT simulation can be replaced by the use of standard diagnostic CT scans for target delineation and planning, which are normally acquired through the radiology department as part of standard patient workup. The goals of this feasibility study are to assess the efficacy, acceptability and scalability of diagnostic-CT-enabled planning, compared to conventional CT simulation planning, for patients receiving PRT to bone, soft tissue and lung disease. METHODS: This is a randomized, phase II study, with 33 PRT patients to be randomized in a 1:2 ratio between conventional CT simulation (Arm 1), and the diagnostic CT enabled planning workflow (Arm 2). Patients will be stratified by treatment target volume (bone and soft tissue metastasis vs. primary or metastatic intrathoracic disease targets). The primary endpoint is the amount of time the patient spends at the cancer centre. Secondary endpoints include efficacy (rate of plan deliverability and rate of plan acceptability on blinded dose distribution review), stakeholder acceptability (based on patient and clinician perception of acceptability questionnaires) and scalability. DISCUSSION: This study will investigate the efficacy, acceptability and scalability of a "sim-free" PRT pathway compared to conventional CT simulation. The workflow may provide opportunity for resource optimization by using pre-existing diagnostic imaging and requires minimal investment due to its similarity to current PRT models. It also offers potential benefit to patients by eliminating an imaging procedure, reducing the amount of time spent at the cancer centre, and expediting time to treatment. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT05233904. Date of registration: February 10, 2022; current version: 1.4 on April 29, 2022.


Subject(s)
Randomized Controlled Trials as Topic , Humans , Clinical Trials, Phase II as Topic
3.
Cureus ; 14(5): e24777, 2022 May.
Article in English | MEDLINE | ID: mdl-35673303

ABSTRACT

BACKGROUND: Adjuvant whole-breast radiotherapy (RT) is a significant part of the standard of care treatment after breast cancer (BC) conserving surgery. Modern techniques including intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) have constituted to better target coverage and critical organs sparing. However, BC survivors are at risk of developing radiation-induced cardiac toxicity. Hence, deep-inspiration breath-hold (DIBH) techniques have been implemented at many centers to further reduce cardiac exposure but require compliance. 4D-CT robust optimization can account for heart intrafractional motion per breathing phase. The optimization has been explored in cardiac sparing of breast IMRT compared to DIBH in a small sample size but has not been evaluated in substructures sparing, nor in VMAT. To provide patients who are not compliant to breath-hold with an optimal treatment approach, various heart sparing techniques need to be evaluated for statistical significance and clinical feasibility. AIM: This retrospective study aimed to provide an extensive dosimetric heart sparing comparison of free-breathing, 4D-CT-based treatment planning, including robust optimization with DIBH-based treatment planning. Combinations of forward and inverse IMRT and VMAT are also considered. METHODS: Fifteen early stage left-sided BC standard treatment plans were selected. Breast, lung, left anterior descending artery (LAD), left ventricle (LV), and the whole heart were contoured on each 4D-CT phase and DIBH CT dataset. Each treatment plan was optimized using forward/inverse IMRT and VMAT on the following CT datasets: DIBH, average 4D-CT, and the complete 4D-CT dataset needed for robust optimization. Dose-volume histograms were used to compare V5GyHeart, mean heart dose, mean and max LAD dose, mean LV dose, and V50%Lung. RESULTS: All RT techniques assessed including 4D robust optimization were clinically feasible. Statistically significant differences in mean heart, LAD and LV dose, max LAD dose, and V5GyHeart (p < 0.01) but no difference in V50%Lung (p = 0.29) were found between different techniques. IMRT DIBH achieved the optimal cardiac and substructure sparing among treatment plans. 4D robust IMRT had significantly greater mean heart and LV dose than DIBH IMRT (p ≤ 0.01), except LAD dose. Among free-breathing methods, no difference in all cardiac and substructure dose parameters was observed (p > 0.2) in comparing forward and inverse IMRT with average 4D-CT, inverse average 4D-CT, and 4D robust with IMRT, and between average 4D-CT VMAT and 4D robust VMAT. Only V5GyHeart and mean LV dose were significantly greater in 4D robust VMAT (p < 0.01) compared to DIBH VMAT. Mean heart and LV doses were significantly reduced (p < 0.01) in DIBH IMRT compared to DIBH VMAT. Moreover, mean heart and LV dose, V5GyHeart were significantly reduced in inverse IMRT average 4D-CT compared to average 4D-CT VMAT (p < 0.02) and in 4D robust IMRT compared to 4D robust VMAT (p < 0.04). CONCLUSION: This study demonstrated the clinical feasibility of 4D robust optimization in limiting the cardiac and substructures dose during free-breathing RT with both IMRT/VMAT for patients who are not compliant with breath-hold RT. However, this study also presents that 4D robust optimization can reduce LAD dose but not fully outperform DIBH or conventional 4D-CT-based planning with IMRT/VMAT in heart sparing in treating early staged left-sided BC patients.

4.
J Urol ; 207(1): 118-126, 2022 01.
Article in English | MEDLINE | ID: mdl-34445893

ABSTRACT

PURPOSE: In 2015, men undergoing radical prostatectomy in Ontario, Canada were recommended to undergo multidisciplinary care by seeing a radiation oncologist or discussion at multidisciplinary rounds before surgery. The a priori target rate was ≥76%. We used population-based data to explore factors associated with not receiving multidisciplinary care prior to radical prostatectomy. MATERIALS AND METHODS: Men who underwent radical prostatectomy for localized prostate cancer in Ontario between 2007 and 2017 were identified using administrative data. Physician billings identified patients who received multidisciplinary care. Multivariable logistic regression was used to predict receipt of multidisciplinary care. RESULTS: A total of 31,485 men underwent radical prostatectomy between 2007 and 2017. Of these patients 28.7% saw a radiation oncologist, 1.2% underwent multidisciplinary discussion and 1.9% had both before surgery. Multidisciplinary care receipt increased from 17.8% in 2007 to 47.8% in 2017 (p <0.001). The odds ratio between the highest and lowest geographic regions was 7.93 (95% CI 6.17-10.18, p <0.001). Lower odds of multidisciplinary care receipt were observed for men further from the nearest cancer center (OR 0.74 per 50 km, 95% CI 0.71-0.78, p <0.001) and higher odds for the highest versus lowest income quintile (OR 1.41, 95% CI 1.29-1.54, p <0.001). Of 128 urologists who performed ≥10 radical prostatectomies between 2016 and 2017, 29 (22.7%) met the target of having ≥76% of men seen for multidisciplinary care prior to surgery. CONCLUSIONS: Despite increasing utilization, many men do not receive multidisciplinary care prior to radical prostatectomy. While geography and the urologist appear to be the greatest factors predicting multidisciplinary care receipt, these factors are closely intertwined.


Subject(s)
Prostatectomy , Prostatic Neoplasms/surgery , Radiation Oncology , Referral and Consultation/statistics & numerical data , Aged , Healthcare Disparities , Humans , Male , Middle Aged , Ontario , Preoperative Period , Prostatectomy/methods
5.
JAMA Netw Open ; 4(9): e2126107, 2021 09 01.
Article in English | MEDLINE | ID: mdl-34546369

ABSTRACT

Importance: Men and women should earn equal pay for equal work. An examination of the magnitude of pay disparities could inform strategies for remediation. Objective: To examine gender-based differences in pay within a large, comprehensive physician population practicing within a variety of payment systems. Design, Setting, and Participants: This cross-sectional study used data from the Ontario Health Insurance Plan (OHIP) in the 2017 to 2018 fiscal year to estimate differences in gross payments between men and women physicians in Ontario, Canada. Pay gaps were calculated annually and daily. Regression analyses were used to control for observable practice characteristics that could account for individual differences in daily pay. In Canada's largest province, Ontario, medical services are predominantly provided by self-employed physicians who bill the province's single payer, OHIP. All physicians who submitted claims to OHIP were included. Data were analyzed from January 2020 to July 2021. Exposures: Physician gender, obtained from the OHIP Corporate Provider Database. Gender is recorded as male or female. Main Outcomes and Measures: Gross clinical payments were tabulated for individual physicians on a daily and annual basis in conjunction with each physician's practice characteristics, setting, and specialty. Results: A total of 31 481 physicians were included in the study sample (12 604 [40.0%] women; 18 877 [60.0%] men; mean [SD] time since graduation, 23.3 [13.6] years), representing 99% of active physicians in Ontario. The unadjusted differences in clinical payments between male and female physicians were 32.8% (95% CI, 30.8%-34.6%) annually and 22.5% (95% CI, 21.2%-23.8%) daily. After accounting for practice characteristics, region, and specialty, the overall daily payment gap was 13.5% (95% CI, 12.3%-14.8%). The pay gap persisted with differing magnitudes when examined by specialty (ranging from 6.6% to 37.6%), practice setting (8.3% to 17.2%), payment model (13.4% to 22.8% for family medicine; 8.0% to 11.6% for other specialties), and rurality (8.0% to 16.5%). Conclusions and Relevance: This cross-sectional study examined differences in magnitude of annual and daily payment gaps and between unadjusted and adjusted gaps. Comparing the gaps for different specialties, geography, and payment systems illustrated the complexity of the issue by showing that the pay gap varied for physicians in different practice settings. As such, multiple directed interventions will be necessary to ensure that all physicians are paid equally for equal work, regardless of gender.


Subject(s)
Income/statistics & numerical data , Physicians, Women/economics , Physicians, Women/statistics & numerical data , Physicians/economics , Physicians/statistics & numerical data , Salaries and Fringe Benefits/statistics & numerical data , Cross-Sectional Studies , Female , Humans , Male , Ontario , Sex Distribution , Sexism/economics
6.
Curr Oncol ; 28(4): 2961-2968, 2021 08 05.
Article in English | MEDLINE | ID: mdl-34436025

ABSTRACT

The need to minimize in-person interactions during the COVID-19 pandemic has led to fewer clinical learning opportunities for trainees. With ongoing utilization of virtual platforms for resident education, efforts to maximize their value are essential. Herein we describe a resident-led quality improvement initiative to optimize remote contouring and virtual contour review. From April to June 2020, radiation oncology (RO) residents at our institution were assigned modified duties. We implemented a program to source and assign cases to residents for remote contouring and to promote and optimize virtual contour review. Resident-perceived educational value was prospectively collected and analyzed. All nine RO residents at our institution (PGY1-5) participated, and 97 cases were contoured during the evaluation period. Introduction of the Remote Contouring and Virtual Review (RECOVR) program coincided with a significant increase in mean cases contoured per week, from 5.5 to 17.3 (p = 0.015), and an increased proportion of cases receiving virtual review, from 14.8% to 58.6% (p < 0.001). Residents reported that the value of immediate feedback during virtual review was similar to that of in-person review (4.6 ± 0.1 vs. 4.5 ± 0.2, p = 0.803) and significantly higher than feedback received post hoc (e.g., email; 3.6 ± 0.2, p < 0.001). The implementation of a remote process for contour review led to significant increases in contouring, and virtual contour review was rated as highly as in-person interactions. Our findings provide a data-driven rationale and framework for integrating remote contouring and virtual review into competency-based medical education.


Subject(s)
COVID-19 , Radiation Oncology , Humans , Pandemics , Quality Improvement , SARS-CoV-2
7.
Adv Radiat Oncol ; 6(5): 100754, 2021.
Article in English | MEDLINE | ID: mdl-34307965

ABSTRACT

As the coronavirus disease 2019 (COVID-19) pandemic continues to disrupt nearly all facets of daily life, residency programs must ensure the safety and wellness of their residents while maintaining a commitment to their training and advancement. In addition to standard clinical training, radiation oncology residency programs integrate highly specialized elements specific to the delivery of radiation therapy. Few publications have addressed the significant effects of the pandemic on medical training and even fewer have addressed concerns specific to radiation oncology. We report our experience developing a resident-led adaptation of our training program in response to the COVID-19 pandemic with the aim of assisting other programs to meet this challenge.

8.
Oncotarget ; 12(2): 81-94, 2021 Jan 19.
Article in English | MEDLINE | ID: mdl-33520113

ABSTRACT

PURPOSE: We develop a multi-centric response predictive model using QUS spectral parametric imaging and novel texture-derivate methods for determining tumour responses to neoadjuvant chemotherapy (NAC) prior to therapy initiation. MATERIALS AND METHODS: QUS Spectroscopy provided parametric images of mid-band-fit (MBF), spectral-slope (SS), spectral-intercept (SI), average-scatterer-diameter (ASD), and average-acoustic-concentration (AAC) in 78 patients with locally advanced breast cancer (LABC) undergoing NAC. Ultrasound radiofrequency data were collected from Sunnybrook Health Sciences Center (SHSC), University of Texas MD Anderson Cancer Center (MD-ACC), and St. Michaels Hospital (SMH) using two different systems. Texture analysis was used to quantify heterogeneities of QUS parametric images. Further, a second-pass texture analysis was applied to obtain texture-derivate features. QUS, texture- and texture-derivate parameters were determined from both tumour core and a 5-mm tumour margin and were used in comparison to histopathological analysis for developing a response predictive model to classify responders versus non-responders. Model performance was assessed using leave-one-out cross-validation. Three standard classification algorithms including a linear discriminant analysis (LDA), k-nearest-neighbors (KNN), and support vector machines-radial basis function (SVM-RBF) were evaluated. RESULTS: A combination of tumour core and margin classification resulted in a peak response prediction performance of 88% sensitivity, 78% specificity, 84% accuracy, 0.86 AUC, 84% PPV, and 83% NPV, achieved using the SVM-RBF classification algorithm. Other parameters and classifiers performed less well running from 66% to 80% accuracy. CONCLUSIONS: A QUS-based framework and novel texture-derivative method enabled accurate prediction of responses to NAC. Multi-centric response predictive model provides indications of the robustness of the approach to variations due to different ultrasound systems and acquisition parameters.

9.
Curr Oncol ; 28(1): 716-725, 2021 01 30.
Article in English | MEDLINE | ID: mdl-33573158

ABSTRACT

Early-stage breast cancer patients comprise a large proportion of patients treated with radiotherapy in Canada. Proponents have suggested that five-fraction hypofractionated radiotherapy for these patients would result in significant cost savings. An assessment of this argument is thus warranted. The FAST-Forward and UK FAST clinical trials each demonstrated that their respective hypofractionated regimens provided equivalent outcomes compared with standard regimens. Thus, a cost-minimization analysis was performed to quantify the potential savings associated with these regimens, which were designated as FAST-Forward 1 (26 Gy/5 fractions/1 week) and FAST-Forward 2 (27 Gy/5 fractions/1 week), and UK FAST 1 (28.5 Gy/5 fractions/5 weeks) and UK FAST 2 (30 Gy/5 fractions/5 weeks). A standard regimen of 42.5 Gy/16 fractions/5 weeks was also included. A comprehensive model of radiotherapy costs for a Canadian cancer centre was created. Time, labour costs, and capital costs were calculated for each regimen and applied using established measures. The total costs per patient for the FAST-Forward trials were $851.77 for FAST-Forward 1 and $874.77 for FAST-Forward 2, providing a total savings of $487.99 and $464.99, respectively. Similarly, the total costs per patient for the FAST trials were $979.75 for UK FAST 1 and $1017.70 for UK FAST 2, providing savings of $360.01 and $322.06, respectively. Following the FAST-Forward 1 regimen results in the greatest reduction of infrastructure and human resources costs at 36.42% compared with the standard. Sensitivity analysis shows a maximum per-patient costs savings ranging from $474.60 to $508.53 for the FAST-Forward 1 trial, which translates to an annual savings of $174,700/year locally and $2.06 million/year province-wide, based on a moderate-to-large size department workload. Compared with a standard radiotherapy regimen, all FAST-Forward and UK FAST hypofractionated regimens provide cost savings for the treatment of early-stage breast cancer. The cost savings associated with each of these equivalent regimens can be directly calculated; activities in this model can easily be adjusted to account for cost variations, allowing other centres to calculate cost impacts specific to their own centres.


Subject(s)
Radiation Dose Hypofractionation , Canada , Costs and Cost Analysis , Follow-Up Studies , Humans , Treatment Outcome
10.
Radiother Oncol ; 156: 120-126, 2021 03.
Article in English | MEDLINE | ID: mdl-33285195

ABSTRACT

BACKGROUND: In patients with hepatocellular carcinoma (HCC), macrovascular invasion (MVI) is associated with a poor prognosis. The purpose of this study is to describe long-term outcomes of patients with HCC and MVI treated with stereotactic body radiation therapy (SBRT). METHODS: Patients with HCC and MVI who were treated with SBRT from January 2003 to December 2016 were analyzed. Patients who had extrahepatic disease or previous liver transplant were excluded. Demographical, clinical, and treatment variables were analyzed. RESULTS: 128 eligible patients with HCC and MVI were treated with SBRT. Median age was 60.5 years (39 to 90 years). Baseline Child-Pugh (CP) score was A5 in 67%, A6 in 20%. Median SBRT dose was 33.3 Gy (range: 27 to 54 Gy) in 5 fractions. Local control at 1 year was 87.4% (95% CI 78.6 to 96.1%). Median overall survival (OS) was 18.3 months (95% CI 11.2 to 21.4 months); ECOG performance status > 1 (HR:1.85, p = 0.0138) and earlier treatment era (HR: 2.20, p = 0.0015) were associated with worsening OS. In 43 patients who received sorafenib following SBRT, median OS was 37.9 months (95% CI 19.5 to 54.4 months). Four patients developed GI bleeding possibly related to SBRT at 2 to 8 months, and 27% (31/112 evaluable patients) had worsening of CP class at three months after SBRT. CONCLUSIONS: SBRT was associated with encouraging outcomes for patients with HCC and MVI, especially in those patients who received sorafenib after SBRT. Randomized phase III trials of SBRT with systemic and/or regional therapy are warranted and ongoing.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Radiosurgery , Carcinoma, Hepatocellular/radiotherapy , Carcinoma, Hepatocellular/surgery , Dose Fractionation, Radiation , Humans , Liver Neoplasms/radiotherapy , Liver Neoplasms/surgery , Middle Aged , Radiosurgery/adverse effects , Retrospective Studies , Sorafenib , Treatment Outcome
11.
Radiother Oncol ; 152: 42-48, 2020 11.
Article in English | MEDLINE | ID: mdl-32717361

ABSTRACT

BACKGROUND AND PURPOSE: Declining prostate brachytherapy utilization has been reported in several studies, despite strong evidence for efficacy and safety compared to alternatives. We sought to evaluate contemporary trends in brachytherapy, external beam radiotherapy (EBRT) and prostatectomy utilization in a publicly funded healthcare system. MATERIALS AND METHODS: Men with localized prostate cancer diagnosed and treated between 2006 and 2017 in Ontario, Canada were identified using administrative data. Men received EBRT, brachytherapy (monotherapy or boost) or prostatectomy as initial definitive management. Multivariable logistic regression evaluated patient-, tumour-, and provider-factors on treatment utilization. RESULTS: 61,288 men were included. On multivariable regression, the odds of receiving brachytherapy boost increased 24% per year (odds ratio [OR]:1.24, 95% CI 1.22-1.26, p < 0.01), brachytherapy monotherapy increased 3% per year (OR:1.03, 95% CI:1.02-1.04, p < 0.01), and prostatectomy declined by 6% per year (OR:0.94, 95% CI 0.93-0.95, p < 0.01). Treatment year was not significant on multivariable modelling of EBRT. In a separate multivariable model limited to those who received radiotherapy, if the first radiation oncologist seen performed brachytherapy, the OR of receiving brachytherapy monotherapy over EBRT was 5.66 (95% CI: 5.11-6.26, p < 0.01) and 2.88 (95% CI: 2.60-3.19, p < 0.01) for brachytherapy boost over EBRT alone. Substantial geographic, provider and patient variation in treatment receipt was observed. CONCLUSION: We found increasing brachytherapy utilization, largely driven by increasing utilization of brachytherapy boost. To our knowledge, this is the first report of increasing brachytherapy use in the era of dose escalated EBRT.


Subject(s)
Brachytherapy , Prostatic Neoplasms , Androgen Antagonists , Humans , Male , Ontario , Prostatic Neoplasms/radiotherapy , Retrospective Studies
12.
PLoS One ; 15(7): e0236182, 2020.
Article in English | MEDLINE | ID: mdl-32716959

ABSTRACT

BACKGROUND: Neoadjuvant chemotherapy (NAC) is the standard of care for patients with locally advanced breast cancer (LABC). The study was conducted to investigate the utility of quantitative ultrasound (QUS) carried out during NAC to predict the final tumour response in a multi-institutional setting. METHODS: Fifty-nine patients with LABC were enrolled from three institutions in North America (Sunnybrook Health Sciences Centre (Toronto, Canada), MD Anderson Cancer Centre (Texas, USA), and Princess Margaret Cancer Centre (Toronto, Canada)). QUS data were collected before starting NAC and subsequently at weeks 1 and 4 during chemotherapy. Spectral tumour parametric maps were generated, and textural features determined using grey-level co-occurrence matrices. Patients were divided into two groups based on their pathological outcomes following surgery: responders and non-responders. Machine learning algorithms using Fisher's linear discriminant (FLD), K-nearest neighbour (K-NN), and support vector machine (SVM-RBF) were used to generate response classification models. RESULTS: Thirty-six patients were classified as responders and twenty-three as non-responders. Among all the models, SVM-RBF had the highest accuracy of 81% at both weeks 1 and week 4 with area under curve (AUC) values of 0.87 each. The inclusion of week 1 and 4 features led to an improvement of the classifier models, with the accuracy and AUC from baseline features only being 76% and 0.68, respectively. CONCLUSION: QUS data obtained during NAC reflect the ongoing treatment-related changes during chemotherapy and can lead to better classifier performances in predicting the ultimate pathologic response to treatment compared to baseline features alone.


Subject(s)
Breast Neoplasms/diagnostic imaging , Breast Neoplasms/drug therapy , Drug Monitoring , Ultrasonography , Adult , Aged , Breast Neoplasms/pathology , Chemotherapy, Adjuvant , Female , Humans , Middle Aged , Multivariate Analysis , Neoadjuvant Therapy , Neoplasm Staging , ROC Curve , Support Vector Machine , Treatment Outcome
13.
Cancer Med ; 9(16): 5798-5806, 2020 08.
Article in English | MEDLINE | ID: mdl-32602222

ABSTRACT

BACKGROUND: This study was conducted in order to develop a model for predicting response to neoadjuvant chemotherapy (NAC) in patients with locally advanced breast cancer (LABC) using pretreatment quantitative ultrasound (QUS) radiomics. METHODS: This was a multicenter study involving four sites across North America, and appropriate approval was obtained from the individual ethics committees. Eighty-two patients with LABC were included for final analysis. Primary tumors were scanned using a clinical ultrasound system before NAC was started. The tumors were contoured, and radiofrequency data were acquired and processed from whole tumor regions of interest. QUS spectral parameters were derived from the normalized power spectrum, and texture analysis was performed based on six QUS features using a gray level co-occurrence matrix. Patients were divided into responder or nonresponder classes based on their clinical-pathological response. Classification analysis was performed using machine learning algorithms, which were trained to optimize classification accuracy. Cross-validation was performed using a leave-one-out cross-validation method. RESULTS: Based on the clinical outcomes of NAC treatment, there were 48 responders and 34 nonresponders. A K-nearest neighbors (K-NN) approach resulted in the best classifier performance, with a sensitivity of 91%, a specificity of 83%, and an accuracy of 87%. CONCLUSION: QUS-based radiomics can predict response to NAC based on pretreatment features with acceptable accuracy.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/drug therapy , Neoadjuvant Therapy , Adult , Aged , Algorithms , Breast Neoplasms/pathology , Breast Neoplasms/surgery , Canada , Chemotherapy, Adjuvant/methods , Female , Humans , Machine Learning , Male , Middle Aged , Prospective Studies , Sensitivity and Specificity , Treatment Outcome , Ultrasonography/methods , United States
14.
Eur J Cancer ; 134: 41-51, 2020 07.
Article in English | MEDLINE | ID: mdl-32460180

ABSTRACT

BACKGROUND: Stereotactic Body Radiation Therapy (SBRT) is a non-invasive ablative treatment for hepatocellular carcinoma (HCC). This report aimed to address the limited availability of long-term outcomes after SBRT for HCC from North America. METHODS: Localized HCC patients without vascular invasion, who were ineligible for other liver-directed therapies and treated with SBRT at the University of Toronto or University of Michigan, were pooled to determine overall survival (OS), cumulative recurrence rates, and ≥ grade-3 toxicity. Multivariable analysis determined factors affecting OS and local recurrence rates. RESULTS: In 297 patients with 436 HCCs (42% > 3 cm), one-, three- and five-year OS was 77·3%, 39·0% and 24·1%, respectively. On Cox proportional hazards regression analysis, liver transplant after SBRT, Child-Pugh A liver function, alpha-fetoprotein ≤ 10 ng/ml, and Eastern Co-operative Oncology Group performance status 0 significantly improved OS (hazard ratio [HR] = 0·06, 95% confidence interval [CI- 0·02-0·25; p<0·001; HR = 0·42, 95% CI = 0·29-0·60, p<0·001; HR = 0·61, 95% CI- 0·44-0·83; p=0·002 and HR = 0·71, 95% CI = 0·51-0·97, p=0·034, respectively). Cumulative local recurrence was 6·3% (95% CI = 0.03-0.09) and 13·3% (95% CI = 0.06-0.21) at one and three years, respectively. Using Cox regression modelling, local control was significantly higher using breath-hold motion management and in HCC smaller than 3 cm (HR = 0.52, 95% CI = 0.58-0.98; p=0.042 and HR = 0.53, 95% CI = 0.26-0.98; p=0.042, respectively). Worsening of Child-Pugh score by ≥2 points three months after SBRT was seen in 15.9%. CONCLUSIONS: SBRT confers high local control and long-term survival in a substantial proportion of HCC patients unsuitable for, or refractory to standard loco-regional treatments. Liver transplant should be considered if appropriate downsizing occurs after SBRT.


Subject(s)
Carcinoma, Hepatocellular/mortality , Liver Neoplasms/mortality , Neoplasm Recurrence, Local/mortality , Radiosurgery/mortality , Adult , Aged , Aged, 80 and over , Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/surgery , Dose Fractionation, Radiation , Female , Follow-Up Studies , Humans , Liver Neoplasms/pathology , Liver Neoplasms/surgery , Male , Middle Aged , Neoplasm Invasiveness , Neoplasm Recurrence, Local/pathology , Neoplasm Recurrence, Local/surgery , Prognosis , Retrospective Studies , Survival Rate , Young Adult
15.
J Med Imaging Radiat Sci ; 50(2): 227-233, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31176430

ABSTRACT

PURPOSE: Exercise may be an alternative strategy to helping early-stage breast cancer (ESBC) patients manage their cancer-related fatigue and anxiety during radiation therapy. This observational study aims to investigate the impact of self-reported exercise on fatigue and anxiety levels pre (T0), mid (T1), and post (T2) radiation therapy in patients with ESBC. METHODS: Following informed consent, subjects completed three standardized questionnaires measuring physical activity, fatigue/quality of life, and anxiety at T0, T1, and T2. RESULTS: A total of 58 female patients (57 ± 9 years) completed this study. Mean activity level at T0 was 2548 (3292) metabolic equivalent units (METs), T1 was 3072 (3974) METs, and T2 was 2963 (2442) METs. There was no significant change between the three time points with measures of physical activity. Many patients moved from the moderately active group at T0 to the active group at T1. The mean T0 score using the quality of life questionnaire was 38.97 (11.30), T1 was 36.93 (11.69), and T2 was 35.36 (11.18). There was no significant change between the three time points with measures of quality of life (P = .211). There was statistical significance at P = .025 at T1 for lower quality of life compared to T0 across all exercise types. There was also statistical significance at P = .026 at T1 for the active group with higher quality of life compared to the inactive one. All three physical activity categories showed a decline in quality of life scores over time. Anxiety decreased between the three time point measurements. Mean T0 score for anxiety was 47.33 (5.95), T1 was 43.16 (6.49), and T2 was 38.48 (8.46). The interaction of exercise level and time is not significant for anxiety (P = .91). There was statistical significance (P = .015) for anxiety at T2 compared to T1 across exercise types. DISCUSSION: This study demonstrated that ESBC patients showed signs of fatigue and anxiety while undergoing radiation therapy regardless of self-reported exercise measured by a physical activity questionnaire. Several trends were observed that showed improved outcomes for patients consistent with previously published studies. The present study highlights a nonsignificant change in fatigue. As fatigue is one of the main side effects from radiation, it may be difficult to demonstrate significance. There are some studies in the field that demonstrate significance between fatigue and exercise with larger sample sizes. The results also highlight a decrease in anxiety from the baseline to the end of treatment. It is postulated that patients become less anxious as treatment progresses due to familiarity of a routine. The present study is limited by several factors including sample size and the study not being a randomized controlled one. CONCLUSIONS: Exercise may reduce anxiety during radiation treatment for ESBC patients. Further investigation is required to assess the impact of fatigue.


Subject(s)
Anxiety , Breast Neoplasms , Exercise/physiology , Fatigue , Adult , Aged , Anxiety/epidemiology , Anxiety/etiology , Breast Neoplasms/complications , Breast Neoplasms/epidemiology , Breast Neoplasms/radiotherapy , Fatigue/epidemiology , Fatigue/etiology , Female , Humans , Middle Aged , Self Report , Surveys and Questionnaires
16.
Radiother Oncol ; 131: 60-65, 2019 02.
Article in English | MEDLINE | ID: mdl-30773188

ABSTRACT

BACKGROUND AND PURPOSE: This study aimed to determine the effects of reducing the dose of contrast agent (CA) in a DCE-MRI scan on inter- and intra-observer variability in the context of MRI-guided target volume delineation for stereotactic body radiation therapy of early stage breast cancer patients. This is in hopes of reducing risks to patients due to findings of residual CA in brain and bone. MATERIALS AND METHODS: Twenty-three patients receiving neoadjuvant radiation therapy were enrolled. Five observers delineated the gross target volume (GTV) using DCE-MRI for guidance. 14/23 patients received the full clinical dose of CA and 9/23 received half. Clinical target volumes (CTV) were created through a 0.5 cm uniform expansion. Several metrics were used to quantify the inter and intra-observer reliability including differences in delineation volume and the reliability coefficient. RESULTS: There were no significant differences in the volume, though half contrast patients had a lower median for both the GTV and CTV (difference of 0.26 cm3 and 1.27 cm3, respectively). All indicated a high degree of agreement between and within observers for both dose groups. However, the full dose group had a greater inter-observer variability, most likely due to the full CA causing more pronounced enhancement in the periphery. CONCLUSIONS: Reducing the dose of contrast agent did not significantly alter inter- or intra-observer variability. These results have prompted our centre to reduce the dose of gadolinium in all patients enrolled in the SIGNAL trial.


Subject(s)
Breast Neoplasms/diagnostic imaging , Breast Neoplasms/radiotherapy , Gadolinium/administration & dosage , Radiosurgery/methods , Radiotherapy Planning, Computer-Assisted/methods , Radiotherapy, Image-Guided/methods , Aged , Aged, 80 and over , Breast Neoplasms/pathology , Contrast Media/administration & dosage , Dose-Response Relationship, Drug , Female , Humans , Magnetic Resonance Imaging/methods , Middle Aged , Neoplasm Staging , Observer Variation , Reproducibility of Results , Tumor Burden
17.
J Med Imaging Radiat Sci ; 49(1): 76-83, 2018 Mar.
Article in English | MEDLINE | ID: mdl-30479293

ABSTRACT

PURPOSE: High-precision radiotherapy relies on accurate anatomic localisation. Urethrography is often used to localise the prostatic apex. However, urethrography is an invasive localisation procedure and may introduce a systemic error. The penile bulb (PB) is contoured to minimise the risk of erectile dysfunction. The purpose of this study is to assess the value of using the PB, as an alternative to urethrography, to localise the prostate. METHODS AND MATERIALS: The PB was localised on 10 patients treated with simplified intensity-modulated arc radiotherapy at computed tomography simulation during treatment weeks 1 and 7. All patients underwent placement of fiducial markers. Urethrography was used only at simulation. Distances from the superior PB contour to the inferior prostate contour, the apex fiducial marker, and to the inferior prostate contour were obtained as well. The PB was contoured by two observers independently. Agreement coefficients and analysis of variance were used to assess reliability between rates and consistency of measurements over time. RESULTS: The PB-apex distance was greater than or equal to the urethrogram-apex distance in 24/30 (80%) measurements, and the median difference was 3 mm and was consistent between raters. The greatest variation in PB-IM distance between weeks was 6 mm, the median was 3 mm, and the agreements of measurements between weeks for raters 1 and 2 were 0.79 and 0.69, respectively. These differences were not statistically different and were consistent with the computed tomography slice thickness. CONCLUSIONS: The PB can be used to identify the prostate apex and can be reliably contoured between observers. Measurements are consistent between patients and through the duration of treatment. The PB distance measurements support studies indicating that urethrography causes a shift of the prostate superiorly. The distance from the PB to prostate apex remains stable during treatment for individual patients but varies between patients.


Subject(s)
Penis/diagnostic imaging , Prostate/diagnostic imaging , Prostatic Neoplasms/diagnostic imaging , Radiotherapy Planning, Computer-Assisted/methods , Fiducial Markers , Humans , Male , Observer Variation , Penis/anatomy & histology , Prostate/anatomy & histology , Prostatic Neoplasms/radiotherapy , Radiography , Radiotherapy, Intensity-Modulated/methods , Tomography, X-Ray Computed/methods , Urethra/diagnostic imaging
18.
Breast Cancer Res Treat ; 172(2): 371-379, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30094551

ABSTRACT

PURPOSE: The aromatase inhibitor (AI) letrozole is a first-line drug in the adjuvant treatment of breast cancer in postmenopausal women. Adherence to AI therapy, including letrozole, remains problematic due to the development of debilitating AI-induced arthralgia. Letrozole is metabolized in the liver by CYP2A6. It remains unknown if plasma letrozole levels or CYP2A6 genetic variation is associated with the development of arthralgia. METHODS: We enrolled 126 female breast cancer patients initiated on letrozole therapy and prospectively collected blood samples at baseline and two follow-up time points to determine letrozole plasma concentrations and CYP2A6 genotype. At each visit, participants completed two validated questionnaires to assess the severity of arthralgia symptoms. RESULTS: More than half (55%) of patients experienced a significant increase in their arthralgia symptoms after initiation of treatment. The clinical variables of body mass index (P = 0.0003) and age (P = 0.0430) were negatively and positively associated with plasma letrozole concentrations, respectively. CYP2A6 genotype was significantly associated with letrozole levels (P < 0.0001), and increased plasma letrozole levels were observed in patients with CYP2A6 reduced-function genotypes. Plasma levels of letrozole and CYP2A6 genotype were not significantly associated with a change in pain score from baseline. CONCLUSIONS: CYP2A6 genotype was a significant predictor of letrozole plasma levels, but was not associated with the development of arthralgia.


Subject(s)
Arthralgia/genetics , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Cytochrome P-450 CYP2A6/genetics , Adult , Aged , Aged, 80 and over , Antineoplastic Agents, Hormonal/administration & dosage , Antineoplastic Agents, Hormonal/adverse effects , Aromatase Inhibitors/administration & dosage , Aromatase Inhibitors/adverse effects , Arthralgia/physiopathology , Breast Neoplasms/blood , Breast Neoplasms/pathology , Female , Genotype , Humans , Letrozole/administration & dosage , Letrozole/blood , Middle Aged
19.
Oncotarget ; 9(29): 20439-20450, 2018 Apr 17.
Article in English | MEDLINE | ID: mdl-29755663

ABSTRACT

PURPOSE: Patterns of failure and long term outcomes were prospectively evaluated following tumor factors-stratified radiation dose for anal/perianal cancer. METHODS: Between 2008-2013, patients with anal/perianal squamous cell carcinoma were accrued to an institutional REB-approved prospective study. All patients were treated with image-guided intensity-modulated radiation therapy (IG-IMRT). Radiation dose selection (27-36 Gy for elective target, and 45-63 Gy for gross target) was based on tumor clinico-pathologic features. Chemotherapy regimen was 5-fluorouracil/mitomycin-C (weeks 1&5). Local [LF], regional failure [RF], distant metastasis [DM], overall- [OS], disease-free [DFS], colostomy-free survival [CFS] and late toxicity were analyzed. RESULTS: Overall, 101 patients were evaluated; median follow-up: 56.5 months; 49.5% male; 34.7% T3/4-category, and 35.6% N+. Median radiation dose was 63 Gy. The most common acute grade ≥3 toxicities were skin (41.6%) and hematological (30.7%). Five-year OS, DFS, CFS, LF, RF, DM rates were 83.4%, 75.7%, 74.7, 13.9%, 4.6% and 5% respectively. Five-year LF for patients with T1-2 and T3-4 disease were 0% and 39.2% respectively. All LF (n = 14, after 63 Gy, in tumors ≥5 cm) were in the high dose volume except one marginal to the high dose volume. All RF (n = 4) were within elective dose volume except one within the high dose volume. On multivariable analysis, T3/4-category predicted for poor DFS, CFS and OS. The overall late grade ≥3 toxicity was 36.2% (mainly anal [20%]). CONCLUSIONS: Individualized radiation dose selection using IG-IMRT resulted in good long term outcomes. However, central failures remain a problem for locally advanced tumors even with high dose radiation (63 Gy/7weeks).

20.
Radiat Oncol ; 13(1): 43, 2018 Mar 15.
Article in English | MEDLINE | ID: mdl-29544511

ABSTRACT

BACKGROUND: Cancer patients frequently search the Internet for treatment options, and hospital websites are seen as reliable sources of knowledge. Guidelines support the use of proton radiotherapy in specific disease sites or on clinical trials. This study aims to evaluate direct-to-consumer advertising content and claims made by proton therapy centre (PTC) websites worldwide. METHODS: Operational PTC websites in English were identified through the Particle Therapy Co-Operative Group website. Data abstraction of website content was performed independently by two investigators. Eight international guidelines were consulted to determine guideline-based indications for proton radiotherapy. Univariate and multivariate logistic regression models were used to determine the characteristics of PTC websites that indicated proton radiotherapy offered greater disease control or cure rates. RESULTS: Forty-eight PTCs with 46 English websites were identified. 60·9% of PTC websites claimed proton therapy provided improved disease control or cure. U.S. websites listed more indications than international websites (15·5 ± 5·4 vs. 10·4 ± 5·8, p = 0·004). The most common disease sites advertised were prostate (87·0%), head and neck (87·0%) and pediatrics (82·6%), all of which were indicated in least one international guideline. Several disease sites advertised were not present in any consensus guidelines, including pancreatobiliary (52·2%), breast (50·0%), and esophageal (43·5%) cancers. Multivariate analysis found increasing number of disease sites and claiming their centre was a local or regional leader in proton radiotherapy was associated with indicating proton radiotherapy offers greater disease control or cure. CONCLUSIONS: Information from PTC websites often differs from recommendations found in international consensus guidelines. As online marketing information may have significant influence on patient decision-making, alignment of such information with accepted guidelines and consensus opinion should be adopted by PTC providers.


Subject(s)
Direct-to-Consumer Advertising/standards , Guideline Adherence , Internet , Neoplasms/radiotherapy , Proton Therapy , Humans
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