Single vs. multiple fraction non-inferiority trial of stereotactic ablative radiotherapy for the comprehensive treatment of oligo-metastases/progression: SIMPLIFY-SABR-COMET.

BACKGROUND: Radiotherapy delivery regimens can vary between a single fraction (SF) and multiple fractions (MF) given daily for up to several weeks depending on the location of the cancer or metastases. With limited evidence comparing fractionation regimens for oligometastases, there is support to explore toxicity levels to nearby organs at risk as a primary outcome while using SF and MF stereotactic ablative radiotherapy (SABR) as well as explore differences in patient-reported quality of life and experience. METHODS: This study will randomize 598 patients in a 1:1 ratio between the standard arm (MF SABR) and the experimental arm (SF SABR). This trial is designed as two randomized controlled trials within one patient population for resource efficiency. The primary objective of the first randomization is to determine if SF SABR is non-inferior to MF SABR, with respect to healthcare provider (HCP)-reported grade 3-5 adverse events (AEs) that are related to SABR. Primary endpoint is toxicity while secondary endpoints include lesional control rate (LCR), and progression-free survival (PFS). The second randomization (BC Cancer sites only) will allocate participants to either complete quality of life (QoL) questionnaires only; or QoL questionnaires and a symptom-specific survey with symptom-guided HCP intervention. The primary objective of the second randomization is to determine if radiation-related symptom questionnaire-guided HCP intervention results in improved reported QoL as measured by the EuroQoL-5-dimensions-5levels (EQ-5D-5L) instrument. The primary endpoint is patient-reported QoL and secondary endpoints include: persistence/resolution of symptom reporting, QoL, intervention cost effectiveness, resource utilization, and overall survival. DISCUSSION: This study will compare SF and MF SABR in the treatment of oligometastases and oligoprogression to determine if there is non-inferior toxicity for SF SABR in selected participants with 1-5 oligometastatic lesions. This study will also compare patient-reported QoL between participants who receive radiation-related symptom-guided HCP intervention and those who complete questionnaires alone. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT05784428. Date of Registration: 23 March 2023.

A modern mold room: Meshing 3D surface scanning, digital design, and 3D printing with bolus fabrication.

PURPOSE: This case series represents an initial experience with implementing 3-dimensional (3D) surface scanning, digital design, and 3D printing for bolus fabrication for patients with complex surface anatomy where traditional approaches are challenging. METHODS AND MATERIALS: For 10 patients requiring bolus in regions with complex contours, bolus was designed digitally from 3D surface scanning data or computed tomography (CT) images using either a treatment planning system or mesh editing software. Boluses were printed using a fused deposition modeling printer with polylactic acid. Quality assurance tests were performed for each printed bolus to verify density and shape. RESULTS: For 9 of 10 patients, digitally designed boluses were used for treatment with no issues. In 1 case, the bolus was not used because dosimetric requirements were met without the bolus. QA tests revealed that the bulk density was within 3% of the reference value for 9 of 12 prints, and with more judicious selection of print settings this could be increased. For these 9 prints, density uniformity was as good as or better than our traditional sheet bolus material. The average shape error of the pieces was less than 0.5 mm, and no issues with fit or comfort were encountered during use. CONCLUSIONS: This study demonstrates that new technologies such as 3D surface scanning, digital design and 3D printing can be safely and effectively used to modernize bolus fabrication.

Diagnosis and Management of Spinal Metastasis of Glioblastoma.

BACKGROUND: When patients with cranial glioblastoma develop weakness, a rare differential diagnosis is spinal metastases. METHODS: Chart and literature reviews were performed. RESULTS: The reported patient had delayed onset spinal drop metastasis that was only detected by magnetic resonance imaging (MRI). A 48-year-old patient had supratentorial glioblastoma, treated with radiotherapy (RT) and concurrent temozolomide followed by six cycles of adjuvant temozolomide. Four years after completion of all treatments (62 months from initial presentation), he developed low backache and weakness in both legs. Positron emission tomography/computed tomography scans demonstrated intracranial recurrence only. Spinal drop metastases were detected only by MRI scan. Local spinal RT 40 Gy in 20 fractions with concurrent and maintenance temozolomide were given. Because of disease progression after nine cycles of temozolomide, systemic therapy was changed to bevacizumab, which greatly improved his symptoms for 4 months before deterioration of mental status. He is still alive with disease at 22 months after diagnosis of spinal metastases (84 months from initial glioblastoma diagnosis). CONCLUSIONS: MRI is the diagnostic imaging of choice for spinal metastases. This illustrative case of delayed-onset spinal metastases shows unusual slow progression. Local RT, temozolomide, and targeted therapy may improve survival. This illustrative case is the first report of bevacizumab as a second-line therapy in drop metastasis of glioblastoma.

Factors Associated with Long-Term Prostate Cancer Survival after Palliative Radiotherapy to a Bone Metastasis and Contemporary Palliative Systemic Therapy: A Retrospective, Population-Based Study.

BACKGROUND: Radiation therapy (RT) is an established palliative treatment for bone metastases; however, little is known about post-radiation survival and factors which impact it. The aim of this study was to assess a population-based sample of metastatic prostate cancer patients receiving palliative radiation therapy to bone metastases and contemporary palliative systemic therapy and identify factors that impact long-term survival. MATERIALS/METHODS: This retrospective, population-based, cohort study assessed all prostate cancer patients receiving palliative RT for bone metastases at a Canadian provincial Cancer program during a contemporary time period. Baseline patient, disease, and treatment characteristics were extracted from the provincial medical physics databases and the electronic medical record. Post-RT Survival intervals were defined as the time interval from the first fraction of palliative RT to death from any cause or date of the last known follow-up. The median survival of the cohort was used to dichotomize the cohort into short- and long-term survivors following RT. Univariable and multivariable hazard regression analyses were performed to identify variables associated with post-RT survival. RESULTS: From 1 January 2018 until 31 December 2019, 545 palliative RT courses for bone metastases were delivered to n = 274 metastatic prostate cancer patients with a median age of 76 yrs (Interquartile range (IQR) 39-83) and a median follow-up of 10.6 months (range 0.2 to 47.9). The median survival of the cohort was 10.6 months (IQR 3.5-25 months). The ECOG performance status of the whole cohort was ≤2 in n = 200 (73%) and 3-4 in n = 67 (24.5%). The most commonly treated sites of bone metastasis were the pelvis and lower extremities n = 130 (47.4%), skull and spine n = 114 (41.6%), and chest and upper extremities n = 30 (10.9%). Most patients had CHAARTED high volume disease n = 239 (87.2%). On multivariable hazard regression analysis, an ECOG performance status of 3-4 (p = 0.02), CHAARTED high volume disease burden (p = 0.023), and non-receipt of systemic therapy (p = 0.006) were significantly associated with worse post-RT survival. CONCLUSION: Amongst metastatic prostate cancer patients treated with palliative radiotherapy to bone metastases and modern palliative systemic therapies, ECOG performance status, CHAARTED metastatic disease burden, and type of first-line palliative systemic therapy were significantly associated with post-RT survival durations.

Social Determinants of Health Screening at an Urban Emergency Department Urgent Care During COVID-19.

INTRODUCTION: Social determinants of health (SDoH) impact patients' health outcomes, yet screening methods in emergency departments (ED) are not consistent or standardized. The SDoH-related health disparities may have widened during the coronavirus 2019 (COVID-19) pandemic, especially among patients who primarily receive their medical care in EDs. We sought to identify SDoH among ED urgent care patients during the COVID-19 pandemic at an urban safety-net hospital, assess the impact of the pandemic on their SDoH, study the feasibility of SDoH screening and resource referrals, and identify preferred methods of resource referrals and barriers to accessing resources. METHODS: Research assistants screened ED urgent care patients using a validated SDoH screener, inquiring about the impact of COVID-19 on their SDoH. A printed resource guide was provided. Two weeks later, a follow-up telephone survey assessed for barriers to resource connection and patients' preferred methods for resource referrals. This study was deemed exempt by our institutional review board. RESULTS: Of the 418 patients presented with a screener, 414 (99.0%) patients completed the screening. Of those screened, 296 (71.5%) reported at least one adverse SDoH, most commonly education (38.7%), food insecurity (35.3%), and employment (31.0%). Housing insecurity was reported by 21.0%. Over half of patients (57.0%) endorsed COVID-19 affecting their SDoH. During follow-up, 156 of 234 (67%) attempted calls were successful and 36/156 (23.1%) reported attempting to connect with a resource, with most attempts made for stable housing (11.0%) and food (7.7%). Reasons for not contacting the provided resources included lack of time (37.8%) and forgetting to do so (26.3%). Patients preferred resource guides to be printed (34.0%) and sent via text message to their mobile devices (25.6%). CONCLUSION: Many urgent care patients of this urban ED reported at least one adverse SDoH, the majority of which were exacerbated by the COVID-19 pandemic. This finding further emphasizes the need to allocate more resources to standardize and expand SDoH screening in EDs. Additionally, hospitals should increase availability of printed or electronic SDoH resource guides, resource navigators, and interpreters both during and after ED visits.

Metformin for Prevention of Anthropometric and Metabolic Complications of Androgen Deprivation Therapy in Prostate Cancer Patients Receiving Radical Radiotherapy: A Phase II Randomized Controlled Trial.

BACKGROUND: Patients with prostate cancer undergoing treatment with radical radiation therapy (RT) plus androgen deprivation therapy (ADT) experience a constellation of deleterious metabolic and anthropometric changes related to hypogonadism that are associated with increased morbidity and mortality. We assessed the effect of metformin versus placebo to blunt the adverse effects of ADT on body weight, waist circumference, and other metabolic parameters. METHODS AND MATERIALS: This phase 2, multicenter, randomized controlled trial (RCT) randomized normoglycemic men with locally advanced prostate cancer receiving radical RT and ADT (18-36 months) in a 1:1 ratio to receive metformin 500 mg by mouth 3 times a day (for 30-36 months) versus identical placebo. RESULTS: From December 2015 to October 2019, 83 men were randomized with median follow-up of 23 months. Baseline mean body mass Index (BMI) of the cohort was 30.2 (range 22.2-52.5). Change in mean weight relative to baseline was lower among men who received metformin compared with placebo at 5 months (-1.80 kg, P = .038), but was not significant with longer follow-up (1 year: +0.16 kg, P = .874). Although participants on ADT had increases in waist circumference in both study arms, metformin did not significantly reduce these changes (1 year: +2.79 cm (placebo) versus +1.46 cm (metformin), P = .336). Low-density lipoprotein (LDL) cholesterol was lower in the metformin arm (-0.32 mmol/L) compared with the placebo arm (-0.03 mmol/L) at 5 months (P = .022), but these differences were not significant with longer follow-up (1 year: -0.17 mmol/L vs -0.19 mmol/L, P = .896). There were no differences in HbA1C, triglyceride, high-density lipoprotein (HDL) cholesterol, and total cholesterol by study arm. CONCLUSIONS: Men receiving radical RT and ADT gained weight and had increases in waist circumference over time that metformin did not significantly mitigate. Although this study did not observe any preventive effect of metformin on the anthropometric and metabolic complications of ADT, metformin continues to be studied in phase 3 RCTs in this patient population to assess its potential antineoplastic effects.

Evaluating a social risk screening and referral program in an urban safety-net hospital emergency department.

Objective: The emergency department (ED) is an opportune venue to screen for unmet social needs and connect patients with social services. This quality improvement study incorporates both qualitative and quantitative data to examine unmet social needs among ED patients and program implementation. Methods: From September 2020 to December 2021, an urban safety-net hospital adult ED implemented a social needs screening and referral program. Trained emergency staff screened eligible patients for 5 social needs (housing, food, transportation, utilities, employment), giving resource guides to patients who screened positive (THRIVE+). We collected screening data from the electronic health record, conducted semi-structured interviews with THRIVE+ patients and clinical staff, and directly observed discharge interactions. Results: Emergency staff screened 58.5% of eligible patients for social risk. Of the screened patients, 27.0% reported at least 1 unmet social need. Of those, 74.8% requested assistance. Screened patients reported housing insecurity (16.3%) as the most prevalent unmet social need followed by food insecurity (13.3%) and unemployment (8.7%). Among interviewed patients, 57.1% recalled being screened, but only 24.5% recalled receiving resource guides. Patients who received guides reported little success connecting with resources and supported universal guide dissemination. Staff expressed preference for warm handoff to social services. Of 13 observed discharge interactions, clinical staff only discussed guides with 2 patients, with no positive endorsement of the guides in any observed interactions. Conclusions: An ED social needs screening program can be moderately feasible and accepted. We identified housing as the most prevalent need. Significant gaps exist between screening and referral, with few patients receiving resources. Further training and workflow optimization are underway.

Endobronchially Implanted Real-Time Electromagnetic Transponder Beacon-Guided, Respiratory-Gated SABR for Moving Lung Tumors: A Prospective Phase 1/2 Cohort Study.

Purpose: Endobronchial electromagnetic transponder beacons (EMT) provide real-time, precise positional data of moving lung tumors. We report results of a phase 1/2, prospective, single-arm cohort study evaluating the treatment planning effects of EMT-guided SABR for moving lung tumors. Methods and Materials: Eligible patients were adults, Eastern Cooperative Oncology Group 0 to 2, with T1-T2N0 non-small cell lung cancer or pulmonary metastasis ≤4 cm with motion amplitude ≥5 mm. Three EMTs were endobronchially implanted using navigational bronchoscopy. Four-dimensional free-breathing computed tomography simulation scans were obtained, and end-exhalation phases were used to define the gating window internal target volume. A 3-mm expansion of gating window internal target volume defined the planning target volume (PTV). EMT-guided, respiratory-gated (RG) SABR was delivered (54 Gy/3 fractions or 48 Gy/4 fractions) using volumetric modulated arc therapy. For each RG-SABR plan, a 10-phase image-guided SABR plan was generated for dosimetric comparison. PTV/organ-at-risk (OAR) metrics were tabulated and analyzed using the Wilcoxon signed-rank pair test. Treatment outcomes were evaluated using RECIST (Response Evaluation Criteria in Solid Tumours; version 1.1). Results: Of 41 patients screened, 17 were enrolled and 2 withdrew from the study. Median age was 73 years, with 7 women. Sixty percent had T1/T2 non-small cell lung cancer and 40% had M1 disease. Median tumor diameter was 1.9 cm with 73% of targets located peripherally. Mean respiratory tumor motion was 1.25 cm (range, 0.53-4.04 cm). Thirteen tumors were treated with EMT-guided SABR and 47% of patients received 48 Gy in 4 fractions while 53% received 54 Gy in 3 fractions. RG-SABR yielded an average PTV reduction of 46.9% (P < .005). Lung V5, V10, V20, and mean lung dose had mean relative reductions of 11.3%, 20.3%, 31.1%, and 20.3%, respectively (P < .005). Dose to OARs was significantly reduced (P < .05) except for spinal cord. At 6 months, mean radiographic tumor volume reduction was 53.5% (P < .005). Conclusions: EMT-guided RG-SABR significantly reduced PTVs of moving lung tumors compared with image-guided SABR. EMT-guided RG-SABR should be considered for tumors with large respiratory motion amplitudes or those located in close proximity to OARs.

Do Sustainable Palliative Single Fraction Radiotherapy Practices Proliferate or Perish 2 Years after a Knowledge Translation Campaign?

In early 2017, the Canadian Partnership Against Cancer and CancerCare Manitoba undertook a comprehensive knowledge translation (KT) campaign to improve the utilization of single fraction radiotherapy (SFRT) over multiple fraction radiotherapy (MFRT) for palliative management of bone metastases. The campaign significantly increased short-term SFRT utilization. We assess the time-dependent effects of KT-derived SFRT utilization 12-24 months removed from the KT campaign in a Provincial Cancer Program. This study identified patients receiving palliative radiotherapy for bone metastases in Manitoba in the 2018 calendar year using the provincial radiotherapy database. The proportion of patients treated with SFRT in 2018 was compared to 2017. Logistic regression analyses identified risk factors associated with MFRT receipt. In 2018, 1008 patients received palliative radiotherapy for bone metastasis, of which 63.3% received SFRT, a small overall increase in SFRT use over 2017 (59.1%). However, 41.1% of ROs demonstrated year-over-year decreases in SFRT utilization, indicative of a time-dependent loss of SFRT prescription habits derived from KT. Although SFRT use increased slightly overall in 2018, evidence of compliance fatigue was observed, suggestive of a time-perishing property of RO prescription behaviours derived from KT methodologies. Verification of the study's findings in larger cohorts would be beneficial. These findings highlight the need for additional longitudinal KT reinforcement practices in the years following KT campaigns.

Impact of Pre-Treatment NLR and Other Hematologic Biomarkers on the Outcomes of Early-Stage Non-Small-Cell Lung Cancer Treated with Stereotactic Body Radiation Therapy.

INTRODUCTION: We evaluated the association of pre-treatment immunologic biomarkers on the outcomes of early-stage non-small-cell lung cancer (NSCLC) patients treated with stereotactic body radiation therapy (SBRT). MATERIALS AND METHODS: In this retrospective study, all newly diagnosed early-stage NSCLC treated with SBRT between January 2010 and December 2017 were screened and included for further analysis. The pre-treatment neutrophil-lymphocyte ratio (NLR), monocyte lymphocyte ratio (MLR), and platelet-lymphocyte ratio (PLR) were calculated. Overall survival (OS) and recurrence-free survival (RFS) were estimated by Kaplan-Meier. Multivariable models were constructed to determine the impact of different biomarkers and the Akaike information criterion (AIC), index of adequacy, and scaled Brier scores were calculated. RESULTS: A total of 72 patients were identified and 61 were included in final analysis. The median neutrophil count at baseline was 5.4 × 109/L (IQR: 4.17-7.05 × 109/L). Median lymphocyte count was 1.63 × 109/L (IQR: 1.29-2.10 × 109/L), median monocyte count was 0.65 × 109/L (IQR: 0.54-0.83 × 109/L), median platelet count was 260.0 × 109/L (IQR: 211.0-302.0 × 109/L). The median NLR was 3.42 (IQR: 2.38-5.04), median MLR was 0.39 (IQR: 0.31-0.53), and median PLR was 156.4 (IQR: 117.2-197.5). On multivariable regression a higher NLR was associated with worse OS (p = 0.01; HR-1.26; 95% CI 1.04-1.53). The delta AIC between the two multivariable models was 3.4, suggesting a moderate impact of NLR on OS. On multivariable analysis, higher NLR was associated with poor RFS (p = 0.001; NLR^1 HR 0.36; 0.17-0.78; NLR^2 HR-1.16; 95% CI 1.06-1.26) with a nonlinear relationship. The delta AIC between the two multivariable models was 16.2, suggesting a strong impact of NLR on RFS. In our cohort, MLR and PLR were not associated with RFS or OS in multivariable models. CONCLUSIONS: Our study suggests NLR, as a biomarker of systemic inflammation, is an independent prognostic factor for OS and RFS. The nonlinear relationship with RFS may indicate a suitable immunological environment is needed for optimal SBRT action and tumoricidal mechanisms. These findings require further validation in independent cohorts.

Pan-Canadian consensus recommendations for proton beam therapy access in Canada.

PURPOSE: Proton Beam Therapy (PBT)is a treatment option for select cancer patients. It is currently not available in Canada. Assessment and referral processes for out-of-country treatment for eligible patients vary by jurisdiction, leading to variability in access to this treatment for Canadian cancer patients. The purpose of this initiative was to develop a framework document to inform consistent and equitable PBT access for appropriate patients through the creation of pan-Canadian PBT access consensus recommendations. MATERIALS AND METHODS: A modified Delphiprocess was used to develop pan-Canadian recommendations with input from 22 PBT clinical and administrative experts across all provinces, external peer-review by provincial cancer and system partners, and feedback from a targeted community consultation. This was conducted by electronic survey and live discussion. Consensus threshold was set at 70% agreement. RESULTS: Fourconsensus rounds resulted in a final set of 27 recommendations divided into three categories: patient eligibility (n = 9); program level (n = 10); and system level (n = 8). Patient eligibility included: anatomic site (n = 4), patient characteristics (n = 3), clinical efficacy (n = 2). Program level included: regulatory and staff requirements (n = 5), equipment and technologies (n = 4), quality assurance (n = 1). System level included: referral process (n = 5), costing, budget impact and quality adjusted life years (n = 2), eligible patient estimates (n = 1). Recommendations were released nationally in June 2021 and distributed to all 43 cancer programs in Canada. CONCLUSION: A pan-Canadian consensus-building approach was successful in creating an evidence-based, peer-reviewed suite of recommendations thatsupportapplication of consistent clinical criteria to inform treatment options, facility set-up and access to high quality proton therapy.

Machine learning for dose-volume histogram based clinical decision-making support system in radiation therapy plans for brain tumors.

PURPOSE: To create and investigate a novel, clinical decision-support system using machine learning (ML). METHODS AND MATERIALS: The ML model was developed based on 79 radiotherapy plans of brain tumor patients that were prescribed a total dose of 60 Gy delivered with volumetric-modulated arc therapy (VMAT). Structures considered for analysis included planning target volume (PTV), brainstem, cochleae, and optic chiasm. The model aimed to classify the target variable that included class-0 corresponding to plans for which the PTV treatment planning objective was met and class-1 that was associated with plans for which the PTV objective was not met due to the priority trade-off to meet one or more organs-at-risk constraints. Several models were evaluated using double-nested cross-validation and an area-under-the-curve (AUC) metric, with the highest performing one selected for further investigation. The model predictions were explained with Shapely additive explanation (SHAP) interaction values. RESULTS: The highest-performing model was Logistic Regression achieving an accuracy of 93.8 ± 4.1% and AUC of 0.98 ± 0.02 on the testing data. The SHAP analysis indicated that the ΔD99% metric for PTV had the greatest influence on the model predictions. The least important feature was ΔDMAX for the left and right cochleae. CONCLUSIONS: The trained model achieved satisfactory accuracy and can be used by medical physicists in a data-driven quality assurance program as well as by radiation oncologists to support their decision-making process in terms of treatment plan approval and potential plan modifications. Model explanation analysis showed that the model relies on clinically valid logic when making predictions.

Do Coordinated Knowledge Translation Campaigns Persuade Radiation Oncologists to Use Single-Fraction Radiation Therapy Compared With Multiple-Fraction Radiation Therapy for Bone Metastases?

PURPOSE: Although level 1 evidence supports the use of single-fraction radiation therapy (SFRT) compared with multiple-fraction radiation therapy (MFRT) for the palliative management of bone metastases, SFRT is underused. In early 2017, the Canadian Partnership Against Cancer and CancerCare Manitoba undertook a comprehensive knowledge translation campaign in Manitoba, Canada featuring educational outreach visits, local consensus meetings, and audit and feedback interventions to encourage greater use of SFRT. This study assessed the impact of this campaign on SFRT use and identified variables associated with MFRT usage. METHODS AND MATERIALS: This retrospective, population-based cohort study identified all patients treated with palliative radiation therapy for bone metastases in Manitoba, Canada, from January 1, 2017, to December 31, 2017, using the provincial radiation therapy database. Baseline characteristics were extracted and tabulated by fractionation schedule. The proportion of patients treated with SFRT in 2017 (postintervention) was compared with the 2016 (preintervention) levels. Univariable and multivariable logistic regression analyses were performed to identify risk factors associated with MFRT use. RESULTS: In 2017, 927 patients received palliative radiation therapy for bone metastasis, of which 548 (59.1%) received SFRT, a 21.1% absolute increase in SFRT use compared with 2016 levels (38.0%). With use of multivariable analysis, variables associated with receipt of MFRT included: complicated bone metastasis, soft tissue extension, hematological primary malignancy, and treatment at a subsidiary center. CONCLUSION: The comprehensive knowledge translation campaign carried out in Manitoba resulted in a significant increase in SFRT use for bone metastases. Continued audit/feedback strategies are recommended to further reinforce knowledge translation efforts supporting SFRT use in the future.

Evaluating the Impact of the COVID-19 Pandemic on New Cancer Diagnoses and Oncology Care in Manitoba.

Individuals with cancer are vulnerable to infection with SARS-CoV-2, the virus causing COVID-19. Physical distancing, the reallocation of health care resources, and the implementation of procedures to reduce the spread of COVID-19 may also have serious consequences for people with cancer. We evaluated the impact of COVID-19 on new cancer diagnoses and oncology care in Manitoba, Canada using an interrupted time series design and data from the Manitoba Cancer Registry and CancerCare Manitoba's (CCMB) electronic medical record. In April 2020, there was a 23% decrease in new cancer diagnoses, a 21% decrease in pathology reports, and a 43% reduction in surgical resections. There was no difference in new cancer diagnoses by August 2020, surgery by July 2020, and pathology reports by September 2020. From April 2020 to June 2021, there was a 13% decrease in radiotherapy (RT) fractions, an 18% decrease in UCC visits, and a 52% decrease in in-person visits. There was no change in intravenous chemotherapy visits per month, first RT visits, or overall patient visits. The impact of COVID-19 on shifts in the stage at diagnosis and survival will be assessed in future analyses.

Gastrointestinal and genitourinary toxicity profiles of metformin versus placebo in men with prostate cancer receiving prostate radiotherapy: interim toxicity results of a double-blinded, multicenter, phase II randomized controlled trial.

Androgen deprivation therapy (ADT) used for prostate cancer (PCa) management is associated with metabolic and anthropometric toxicity. Metformin given concurrent to ADT is hypothesized to counteract these changes. This planned interim analysis reports the gastrointestinal and genitourinary toxicity profiles of PCa patients receiving ADT and prostate/pelvic radiotherapy plus metformin versus placebo as part of a phase 2 randomized controlled trial. Men with intermediate or high-risk PCa were randomized 1:1 to metformin versus placebo. Both groups were given ADT for 18-36 months with minimum 2-month neoadjuvant phase prior to radiotherapy. Acute gastrointestinal and genitourinary toxicities were quantified using CTCAE v4.0. Differences in ≥ grade 2 toxicities by treatment were assessed by chi-squared test. 83 patients were enrolled with 44 patients randomized to placebo and 39 randomized to metformin. There were no significant differences at any time point in ≥ grade 2 gastrointestinal toxicities or overall gastrointestinal toxicity. Overall ≥ grade 2 gastrointestinal toxicity was low prior to radiotherapy (7.9% (placebo) vs. 3.1% (metformin), p = 0.39) and at the end of radiotherapy (2.8% (placebo) vs 3.1% (metformin), p = 0.64). There were no differences in overall ≥ grade 2 genitourinary toxicity between treatment arms (19.0% (placebo) vs. 9.4% (metformin), p = 0.30). Metformin added to radiotherapy and ADT did not increase rates of ≥ grade 2 gastrointestinal or genitourinary toxicity and is generally safe and well-tolerated.

Bracing for impact with new 4R's in the COVID-19 pandemic - A provincial thoracic radiation oncology consensus.

As COVID-19 pandemic continues to explode, cancer centers worldwide are trying to adapt and are struggling with this constantly changing scenario. Intending to ensure patient safety and deliver quality care, we sought consensus on the preferred thoracic radiation regimen in a Canadian province with 4 new R's of COVID era.

Working in the dark: Interaction with a sub clinical COVID-19 subject and lessons learned.

Subclinical COVID-19 subjects pose a significant challenge. We present a very close clinical interaction with a subclinical COVID-19 subject that met the "standard screening criteria" and is unique in several ways. Learning from our experience, we suggest close attention should be paid to any unexpected findings such as groundglass opacity on CT as it could help early identification of subclinical COVID-19 infection.

Population-based Assessment of Intermittent Androgen Deprivation Therapy Utilization for Relapsed, Nonmetastatic, Hormone-sensitive Adenocarcinoma of the Prostate.

OBJECTIVES: Androgen deprivation therapy (ADT) is the standard of care for men with nonmetastatic hormone-sensitive prostate cancer (nmHSPC) after treatment failure. Although intermittent ADT (iADT) is noninferior to continuous ADT for prostate cancer outcomes, with superior quality of life and cost-to-benefit ratio, little is known regarding its real-world utilization. The authors aimed to determine the utilization of iADT in a Canadian Provincial Cancer Program for relapsed nmHSPC and identified risk factors associated with the nonreceipt of iADT. MATERIALS AND METHODS: This retrospective population-based cohort study used linked administrative databases to identify all patients with relapsed nmHSPC from 2012 to 2016 and quantified ADT prescription history. Patients were defined as iADT eligible if prostate-specific antigen (PSA) was <4 ng/mL and trending downwards on ≥2 sequential PSAs after ≥6 months of ADT. Univariable and multivariable logistic regression analyses were performed to determine factors associated with nonreceipt of iADT. RESULTS: A total of 601 men with relapsed, nmHSPC were included with a median age at relapse of 73 (range, 46 to 96), pre-ADT PSA of 12.2 ng/mL, and a median pre-ADT PSA doubling time of 7.8 months. 80.9% of the cohort were eligible to receive iADT and 74.4% were treated with iADT. On multivariable analysis, patients originally treated with surgery (odds ratio [OR], 0.19; 95% confidence interval [CI], 0.08-0.46) or having a Gleason Score ≥8 (OR, 0.30; 95% CI, 0.12-0.78) had decreased odds of receipt of iADT. Patients with longer PSA doubling times were more likely to receive iADT (OR, 2.71; 95% CI, 1.17-6.31). CONCLUSIONS: The utilization of iADT was relatively common for men in Manitoba during the study period, however, the uptake of iADT can be improved among identified subgroups.

Role of Stereotactic Body Radiation Therapy in Early Stage Small Cell Lung Cancer in the Era of Lung Cancer Screening: A Systematic Review.

With the obvious benefit from low dose computed tomography to reduce the lung cancer-specific mortality, lung cancer screening is on the rise. With the implementation of the screening programs, diagnosis of early stage lung cancer is expected to increase, and small cell lung cancer (SCLC) would account for 10% of screen-detected lung cancer. Apart from Concurrent chemoradiation (CRT), the present guidelines virtually do not support other options for radiation (RT). There is a paucity of data addressing the role of Stereotactic Body Radiation Therapy (SBRT) in SCLC and we conducted the current systematic review on this topic. We systematically searched literature using the electronic databases PubMed and Embase with no language, year or publication status restrictions. After removal of duplicate records, 3469 screened, 3446 excluded with reasons, 23 full-text articles were assessed for eligibility, and 7 studies (8 reports) were included. Unsuitability for surgery or refusal for surgery was the most common reason for the use of SBRT in early stage SCLC in the included studies. Variable patterns of SBRT-chemotherapy (CT) sequencing including concurrent, pre-CT and post-CT and radiation doses were noted. Within the reported studies overall survival (OS) at 1 year, 2 year and 3 year varied from 63% to 87%, 37% to 72%, and 35% to 72%, respectively. Distant metastasis was the most common pattern of failure ranging from 38% to 53%. There was no increase in the reported grade III toxicity. SBRT could be a potential option in stage I SCLC with comparable outcomes with no added toxicity. Acknowledging the limitations and absence of high-quality data, presently cautious interpretation is warranted and further studies are needed to establish the role of SBRT in SCLC.

The Second Victim Phenomenon: Perspective of Canadian Radiation Therapists.

INTRODUCTION: Clinical incidents are an unfortunate reality in the health care system. Patients and their families are the first victims of these incidents. The health care providers involved in the error are considered the second victims. This research aimed to evaluate the level of awareness of the second victim phenomenon (SVP) in Canadian radiation therapists, determine the post-incident emotional and physical reactions experienced, and determine the existing and/or recommended systems for support. METHODS: Mixed method design comprised two phases. In phase I, Canadian radiation therapists were invited to view an informational presentation about the SVP and complete an online survey. In phase II, participants partook in an online discussion forum. RESULTS: Survey results indicate that 31% of respondents were previously aware of the SVP and 86% of respondents report having been involved in a clinical incident. In addition, the results confirm that Canadian radiation therapists who have been involved in health care-related incidents do experience emotional and physical reactions. Most respondents indicated they lacked appropriate organizational support to help them recover from the clinical incident. Support from a colleague is the preferred method of support immediately after the incident. Finally, survey respondents indicated a clear desire for implementation of defined processes for postclinical incident supports. DISCUSSION: The reported level of awareness of the SVP surprised the authors as it was anticipated to be lower; however, there is an obvious need for greater knowledge of the subject. Reported frequency of involvement in a clinical incident as well as the post-clinical reactions experienced are comparable for other health care providers as indicated in the literature. Survey results revealed that emotional and physical reactions were experienced to a greater degree in those unfamiliar with the SVP, indicating potential value to adding an educational component to radiation therapist's training programs as well as on the job training for staff in the workforce. Most respondents requested specific methods of support for recovery after a clinical incident. In addition, an unexpected number of radiation therapists indicated the need for a "no-blame" work environment, which was an unanticipated finding. CONCLUSION: This study highlights the lack of awareness of the SVP in Canadian radiation therapists. It identifies the gap between the needs of the second victims and the perceived lack of supports offered by their facilities. This issue is important for organizations wanting to positively manage clinical incidents and create a culture of safety for the patients and employees.