Radiation Oncologist Consultations Prior to Radical Prostatectomy: Disparities and Opportunities.

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.

A Framework for Assuring the Safety, Training, Evaluation, and Wellness of Radiation Oncology Residents During the COVID-19 Pandemic (ASTEROiD-COVID19).

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.

Remote Contouring and Virtual Review during the COVID-19 Pandemic (RECOVR-COVID19): Results of a Quality Improvement Initiative for Virtual Resident Training in Radiation Oncology.

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.

Is prostate brachytherapy a dying art? Trends and variation in the definitive management of prostate cancer in Ontario, Canada.

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.

Reducing the dose of gadolinium-based contrast agents for DCE-MRI guided SBRT: The effects on inter and intra observer variability for preoperative target volume delineation in early stage breast cancer patients.

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.

Online advertising and marketing claims by providers of proton beam therapy: are they guideline-based?

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.

Anatomic features of interest in women at risk of cardiac exposure from whole breast radiotherapy.

BACKGROUND AND PURPOSE: Left-sided breast radiotherapy (RT) can result in cardiac exposure. This study aims to identify predictive anatomic features in women requiring breath-hold (RT(BH)) for cardiac sparing during adjuvant whole breast RT. MATERIAL AND METHODS: We retrospectively reviewed free-breathing (FB) CT scans of 80 women previously treated with left-sided breast RT. Unfavourable cardiac anatomy was defined as the number of consecutive axial CT slices (2 mm) in which the anterior chest wall contacted the heart (Contact(Heart)) or left ventricle (Contact(LV)). The sternal angle and Haller Index (HI) were used to measure chest concavity. Position and volume of post-operative cavity was also quantified. RESULTS: Heart mean dose (D(mean)) was strongly correlated with Contact(LV) (r=0.625, p<0.001) and Contact(Heart) (r=0.524, p<0.001) but not significantly correlated with tumor size, cavity volume, heart volume, cavity distance to chest wall, sternal angle, or HI. ROC analysis of Contact(Heart) was most predictive of the need for breath-hold (RT(BH)) technique [Area Under Curve=0.815 (SE: 0.048; 95% CI: 0.721-0.91)] and ⩾25 Contact(Heart) CT slices predicted for heart D(mean) ⩾1.7 Gy (68% sensitivity and 82% specificity). CONCLUSION: Contact(Heart) on FB CT of ⩾25 axial slices (2 mm), ⩾50 mm of para-sagittal heart contact, was predictive of higher heart D(mean) and suggest a potential need for RT(BH).

Automation and intensity modulated radiation therapy for individualized high-quality tangent breast treatment plans.

PURPOSE: To demonstrate the large-scale clinical implementation and performance of an automated treatment planning methodology for tangential breast intensity modulated radiation therapy (IMRT). METHODS AND MATERIALS: Automated planning was used to prospectively plan tangential breast IMRT treatment for 1661 patients between June 2009 and November 2012. The automated planning method emulates the manual steps performed by the user during treatment planning, including anatomical segmentation, beam placement, optimization, dose calculation, and plan documentation. The user specifies clinical requirements of the plan to be generated through a user interface embedded in the planning system. The automated method uses heuristic algorithms to define and simplify the technical aspects of the treatment planning process. RESULTS: Automated planning was used in 1661 of 1708 patients receiving tangential breast IMRT during the time interval studied. Therefore, automated planning was applicable in greater than 97% of cases. The time for treatment planning using the automated process is routinely 5 to 6 minutes on standard commercially available planning hardware. We have shown a consistent reduction in plan rejections from plan reviews through the standard quality control process or weekly quality review multidisciplinary breast rounds as we have automated the planning process for tangential breast IMRT. Clinical plan acceptance increased from 97.3% using our previous semiautomated inverse method to 98.9% using the fully automated method. CONCLUSIONS: Automation has become the routine standard method for treatment planning of tangential breast IMRT at our institution and is clinically feasible on a large scale. The method has wide clinical applicability and can add tremendous efficiency, standardization, and quality to the current treatment planning process. The use of automated methods can allow centers to more rapidly adopt IMRT and enhance access to the documented improvements in care for breast cancer patients, using technologies that are widely available and already in clinical use.

Radiotherapy Treatment Review: A Prospective Evaluation of Concordance between Clinical Specialist Radiation Therapist and Radiation Oncologist in Patient Assessments.

PURPOSE: This study assessed the concordance of patient assessments performed during weekly radiotherapy treatment reviews between the breast site clinical specialist radiation therapist (CSRT) and radiation oncologist (RO). METHODS AND MATERIALS: A CSRT and RO independently assessed patients attending a breast radiotherapy review clinic and graded their toxicities according to the Common Terminology Criteria for Adverse Events v.3.0. Both observers were blinded to each other's assessments. The concordance rates and agreement levels, indicated by the Kappa statistics, were calculated with the RO considered as the gold standard. RESULTS: Twenty-nine consecutive patients were prospectively reviewed over 12 weeks. High concordance occurred between CSRT and RO assessments, with an overall concordance rate of 96% for all evaluated toxicities. The concordance rates for non-zero grade toxicities ranged from 76% to 100%. There was almost perfect agreement between the CSRT and RO in toxicity grading for dermatitis (P < .05), whereas fair agreement was observed for hyperpigmentation (P < .05). Overall, there was increasing agreement between the CSRT and RO assessments over time. CONCLUSION: Common side effects experienced by patients receiving breast radiotherapy as detected and graded by the CSRT were highly comparable to those of the RO. This study lends support for CSRT involvement in treatment review assessments for this patient population.

Evaluation of variability in seroma delineation between clinical specialist radiation therapist and radiation oncologist for adjuvant breast irradiation.

PURPOSE: Breast cancer is managed by a multidisciplinary team with a goal for the timely provision of high quality care. Given radiation oncologist (RO) time constraints, an opportunity arises for task delegation of breast seroma target delineation to an advanced practice clinical specialist radiation therapist (CSRT) with clinical and technical expertise to facilitate treatment planning. To explore this further, we quantitatively evaluated the variability in post-surgical seroma delineation between the CSRT and ROs. METHODS: Specialized site specific training was provided to the CSRT, who, with 7 ROs, independently contoured the seroma and graded its clarity, using the cavity visualization score (CVS), for 20 patients with clinical stage Tis-2N0 breast tumors. The conformity indices were analyzed for all possible pairs of delineations. The estimated "true" seroma contour was derived from the RO contours using the simultaneous truth and performance level estimation algorithm. Generalized kappa coefficient and center of mass metrics were used to examine the performance level of the CSRT in seroma delineations. RESULTS: The CVS of the CSRT correlated well with the mean RO-group CVS, (Spearman ρ = 0.87, P < .05). The mean seroma conformity index for the RO group was 0.61 and 0.65 for the CSRT; a strong correlation was observed between the RO and CSRT conformity indices (Spearman ρ = 0.95, P < .05). Almost perfect agreement levels were observed between the CSRT contours and the STAPLE RO consensus contours, with an overall kappa statistic of 0.81 (P < .0001). The average center of mass shift between the CSRT and RO consensus contour was 1.69 ± 1.13 mm. CONCLUSIONS: Following specialized education and training, the CSRT delineated seroma targets clinically comparable with those of the radiation oncologists in women with early breast tumors suitable for accelerated partial breast or whole breast radiotherapy following lumpectomy. This study provides support for potential task delegation of breast seroma delineation to the CSRT in our current multidisciplinary environment. Further study is needed to assess the impact of this role expansion on radiotherapy system efficiency.

Automated planning of tangential breast intensity-modulated radiotherapy using heuristic optimization.

PURPOSE: To present an automated technique for two-field tangential breast intensity-modulated radiotherapy (IMRT) treatment planning. METHOD AND MATERIALS: A total of 158 planned patients with Stage 0, I, and II breast cancer treated using whole-breast IMRT were retrospectively replanned using automated treatment planning tools. The tools developed are integrated into the existing clinical treatment planning system (Pinnacle(3)) and are designed to perform the manual volume delineation, beam placement, and IMRT treatment planning steps carried out by the treatment planning radiation therapist. The automated algorithm, using only the radio-opaque markers placed at CT simulation as inputs, optimizes the tangential beam parameters to geometrically minimize the amount of lung and heart treated while covering the whole-breast volume. The IMRT parameters are optimized according to the automatically delineated whole-breast volume. RESULTS: The mean time to generate a complete treatment plan was 6 min, 50 s ± 1 min 12 s. For the automated plans, 157 of 158 plans (99%) were deemed clinically acceptable, and 138 of 158 plans (87%) were deemed clinically improved or equal to the corresponding clinical plan when reviewed in a randomized, double-blinded study by one experienced breast radiation oncologist. In addition, overall the automated plans were dosimetrically equivalent to the clinical plans when scored for target coverage and lung and heart doses. CONCLUSION: We have developed robust and efficient automated tools for fully inversed planned tangential breast IMRT planning that can be readily integrated into clinical practice. The tools produce clinically acceptable plans using only the common anatomic landmarks from the CT simulation process as an input. We anticipate the tools will improve patient access to high-quality IMRT treatment by simplifying the planning process and will reduce the effort and cost of incorporating more advanced planning into clinical practice.

Interfraction and intrafraction changes in amplitude of breathing motion in stereotactic liver radiotherapy.

PURPOSE: Interfraction and intrafraction changes in amplitude of liver motion were assessed in patients with liver cancer treated with kV cone beam computed tomography (CBCT)-guided stereotactic body radiation therapy (SBRT). METHODS AND MATERIALS: A total of 314 CBCTs obtained with the patient in the treatment position immediately before and after each fraction, and 29 planning 4DCTs were evaluated in 29 patients undergoing six-fraction SBRT for unresectable liver cancer, with (n = 15) and without (n = 14) abdominal compression. Offline, the CBCTs were sorted into 10 bins, based on phase of respiration. Liver motion amplitude was measured using liver-to-liver alignment from the end-exhale and end-inhale CBCT and four-dimensional CT reconstructions. Inter- and intrafraction amplitude changes were measured from the difference between the pre-SBRT CBCTs relative to the planning four-dimensional CT, and from the pre-SBRT and post-SBRT CBCTs, respectively. RESULTS: Mean liver motion amplitude for all patients (range) was 1.8 (0.1-7.0), 8.0 (0.1-18.8), and 4.3 (0.1-12.1) mm in the mediolateral (ML), craniocaudal (CC), and anteroposterior (AP) directions, respectively. Mean absolute inter- and intrafraction liver motion amplitude changes were 1.0 (ML), 1.7 (CC), and 1.6 (AP) mm and 1.3 (ML), 1.6 (CC), and 1.9 (AP) mm, respectively. No significant correlations were found between intrafraction amplitude change and intrafraction time (range, 4:56-25:37 min:sec), and between inter- and intrafraction amplitude changes and liver motion amplitude. Intraobserver reproducibility (sigma, n = 29 fractions) was 1.3 (ML), 1.4 (CC), and 1.4 (AP) mm. CONCLUSIONS: For the majority of liver SBRT patients, the change in liver motion amplitude was minimal over the treatment course and showed no apparent relationships with the magnitude of liver motion and intrafraction time.