The COVID-19 pandemic and its effects on follow-up of patients with early breast cancer: A patient survey.

PURPOSE: Despite limited evidence supporting its effectiveness, most guidelines recommend long-term, routinely scheduled in-person surveillance of patients with early breast cancer (EBC). The COVID-19 pandemic led to increased use of virtual care. This survey evaluated patient perspectives on follow-up care. METHODS: Patients with EBC undergoing surveillance were surveyed about follow-up protocols, perceptions, and interest in clinical trials assessing different follow-up strategies. RESULTS: Of 402 approached patients 270 completed the survey (response rate 67%). Median age 62.5 years (range 25-86) and median time since breast cancer diagnosis was 3.8 years (range < 1-33 years). Most (n = 148/244, 60%) were followed by more than one provider. Routine follow-ups with breast examination were mostly conducted by medical/radiation oncologists every 6 months (n = 110/236, 46%) or annually (n = 106/236, 44%). Participants felt routine follow-up was useful to monitor for recurrence, manage side effects of cancer treatment and to provide support/reassurance. Most participants felt regular follow-up care would detect recurrent cancer earlier (n = 214/255, 96%) and increase survival (n = 218/249, 88%). The COVID-19 pandemic reduced the number of in-person visits for 54% of patients (n = 63/117). Patients were concerned this reduction of in-person visits would lead to later detection of both local (n = 29/63, 46%) and distant recurrences (n = 25/63, 40%). While many felt their medical and radiation oncologists were the most suited to provide follow-up care, 55% felt comfortable having their primary care provider (PCP) conduct surveillance. When presented with a scenario where follow-up has no effect on earlier detection or survival, 70% of patients still wanted routine in-person follow-up for reassurance (63%) with the goal of earlier recurrence detection (56%). CONCLUSIONS: Despite limited evidence of effectiveness of routine in-person assessment, patients continue to place importance on regularly scheduled in-person follow-up.

Impact of COVID-19 Pandemic on Readmission Rates Following Colorectal Surgery: A Retrospective Cohort Study.

BACKGROUND: The COVID-19 pandemic placed increased pressure to discharge patients early; this could have resulted in rushed discharges requiring patients to return to hospital. The impact of the pandemic on readmission after colorectal surgery is unknown. METHODS: The National Surgical Quality Improvement Program (ACS-NSQIP) database was used to compare patients undergoing elective colorectal surgery in 2019 and 2020, prior to and during the COVID-19 pandemic. Multivariable logistic regression was used to examine variables associated with readmission. Propensity score matching was then used to compare patients in the pre-pandemic and pandemic cohorts. RESULTS: A total of 72,874 colorectal cases were included. There were 17.7% less cases in 2020. Rate of readmission was similar in both groups (9.6% vs. 9.4%). There were fewer patients discharged to a facility such as nursing facility or rehabilitation center in 2020, with more patients discharged home. Year was not associated with readmission on multivariable analysis. In the matched cohort, readmission rates did not differ (9.7% vs. 9.3% p = 0.129) nor did mortality (0.8% vs. 0.8% p = 0.686). CONCLUSIONS: No difference in readmission rates before or during the COVID-19 pandemic was observed; suggesting increased pressure to keep patients out of hospital in the COVID-19 pandemic did not result in patients being rushed home requiring repeat admission. More patients were discharged home with fewer to rehabilitation or nursing facilities in 2020, suggesting success with avoiding transitional services in the right setting.

PET/MRI Assessment of Acute Cardiac Inflammation 1 Month After Left-Sided Breast Cancer Radiation Therapy.

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.

Are Radiation Target Volumes for Postmastectomy Radiation Therapy Too Large? Initial Report of the Complication Avoidance of Reconstruction Implant Radiation Therapy (CARIT) Study.

Following mastectomy for breast cancer, women may choose implant-based reconstruction for many reasons, such as cosmesis, self-identity, and the ability to wear particular items of clothing. However, postmastectomy radiation therapy (PMRT) can compromise these cosmetic goals, including as much as a 40% loss of implant rate. To minimize the risk of radiation toxicity, it is important to consider how clinical target volumes (CTVs) can be optimized in PMRT to preserve the implant and reduce complications. Typically, guidelines from organizations such as the Radiation Oncology Group are used, which include regions previously encompassed by tangential fields. This includes all structures below the pectoralis muscle, such as the chest wall, where the risk of recurrence is negligible; this technique often requires incidental inclusion of portions of the lung and heart plus circumferential radiation of the implant. We present the preliminary single institution case series of a technique of complication avoidance of reconstruction implant radiation therapy, called CARIT, where the chest wall, and a large proportion of the implant, is not irradiated. In a retrospective review of 30 cases in which CARIT has been attempted, it was found that 24% of patients treated required a second surgery due to Baker grade III/IV capsular contracture. Using the Modified Harvard Harris Cosmetic Scale, 66.5% of patients had cosmetic outcomes rated as "good" or "excellent". CARIT could offer a technique to reduce complications in postmastectomy implant-based reconstruction patients, with our next steps focusing on improving dosimetry, and formally comparing the cosmesis and tumor control aspects with commonly used techniques.

Complications From Postmastectomy Radiation Therapy in Patients Undergoing Immediate Breast Reconstruction: A Population-Based Study.

Purpose: Previous studies have shown an increase in the number of women electing for immediate breast reconstruction at the time of mastectomy. Although often not known at the time, some of these women will require postoperative radiation therapy. The purpose of this study was to investigate if exposure to radiation therapy after mastectomy with immediate breast reconstruction is associated with an increased risk of further surgery to manage complications arising from radiation. Methods and Materials: This retrospective, population-based cohort study included all patients who underwent mastectomy with immediate reconstruction from 2007 to 2014 in the province of Ontario, Canada. Exposure to adjuvant radiation therapy was captured using data from Ontario Health. The study outcome was reoperation for breast reconstruction performed during the follow-up window. Cox proportional hazard models were used to assess the effect of radiation therapy exposure on risk of breast reconstruction reoperation. Results: We identified 2342 patients who underwent mastectomy with immediate reconstruction over an 8-year period in Ontario, of whom 378 (16.1%) underwent adjuvant radiation therapy. Patients who received radiation were significantly more likely to undergo reoperation during follow-up (hazard ratio, 1.76; 95% confidence interval, 1.49-2.08; P < .0001). Patients with implant-based reconstructions (n = 1629, 69.6%) were not more likely to undergo reoperation than those with flap-based procedures (n = 713, 30.4%) (hazard ratio, 1.01; 95% confidence interval, 0.85-1.21; P = .885). Conclusions: Adjuvant radiation therapy initiated after mastectomy with immediate breast reconstruction is associated with an increased risk of additional breast reconstruction surgery, regardless of the type of reconstruction used. Patients with breast cancer who choose to undergo immediate reconstruction after mastectomy should be advised that additional reconstruction procedures may be required.

Efficacy and safety of extended duration to perioperative thromboprophylaxis with low molecular weight heparin on disease-free survival after surgical resection of colorectal cancer (PERIOP-01): multicentre, open label, randomised controlled trial.

OBJECTIVE: To determine the efficacy and safety of extended duration perioperative thromboprophylaxis by low molecular weight heparin when assessing disease-free survival in patients undergoing resection for colorectal cancer. DESIGN: Multicentre, open label, randomised controlled trial. SETTINGS: 12 hospitals in Quebec and Ontario, Canada, between 25 October 2011 and 31 December 2020. PARTICIPANTS: 614 adults (age ≥18 years) were eligible with pathologically confirmed invasive adenocarcinoma of the colon or rectum, no evidence of metastatic disease, a haemoglobin concentration of ≥8 g/dL, and were scheduled to undergo surgical resection. INTERVENTIONS: Random assignment to extended duration thromboprophylaxis using daily subcutaneous tinzaparin at 4500 IU, beginning at decision to operate and continuing for 56 days postoperatively, compared with in-patient postoperative thromboprophylaxis only. MAIN OUTCOME MEASURES: Primary outcome was disease-free survival at three years, defined as survival without locoregional recurrence, distant metastases, second primary (same cancer), second primary (other cancer), or death. Secondary outcomes included venous thromboembolism, postoperative major bleeding complications, and five year overall survival. Analyses were done in the intention-to-treat population. RESULTS: The trial stopped recruitment prematurely after the interim analysis for futility. The primary outcome occurred in 235 (77%) of 307 patients in the extended duration group and in 243 (79%) of 307 patients in the in-hospital thromboprophylaxis group (hazard ratio 1.1, 95% confidence interval 0.90 to 1.33; P=0.4). Postoperative venous thromboembolism occurred in five patients (2%) in the extended duration group and in four patients (1%) in the in-hospital thromboprophylaxis group (P=0.8). Major surgery related bleeding in the first postoperative week was reported in one person (<1%) in the extended duration and in six people (2%) in the in-hospital thromboprophylaxis group (P=0.1). No difference was noted for overall survival at five years in 272 (89%) patients in the extended duration group and 280 (91%) patients in the in-hospital thromboprophylaxis group (hazard ratio 1.12; 95% confidence interval 0.72 to 1.76; P=0.1). CONCLUSIONS: Extended duration to perioperative anticoagulation with tinzaparin did not improve disease-free survival or overall survival in patients with colorectal cancer undergoing surgical resection compared with in-patient postoperative thromboprophylaxis alone. The incidences of venous thromboembolism and postoperative major bleeding were low and similar between groups. TRIAL REGISTRATION: ClinicalTrials.gov NCT01455831.

Canadian Expert Opinion on Breast Reconstruction Access: Strategies to Optimize Care during COVID-19.

BACKGROUND: Breast reconstructive services are medically necessary, time-sensitive procedures with meaningful health-related quality of life benefits for breast cancer survivors. The COVID-19 global pandemic has resulted in unprecedented restrictions in surgical access, including access to breast reconstructive services. A national approach is needed to guide the strategic use of resources during times of fluctuating restrictions on surgical access due to COVID-19 demands on hospital capacity. METHODS: A national team of experts were convened for critical review of healthcare needs and development of recommendations and strategies for patients seeking breast reconstruction during the pandemic. Following critical review of literature, expert discussion by teleconference meetings, and evidenced-based consensus, best practice recommendations were developed to guide national provision of breast reconstructive services. RESULTS: Recommendations include strategic use of multidisciplinary teams for patient selection and triage with centralized coordinated use of alternate treatment plans during times of resource restrictions. With shared decision-making, patient-centered shifting and consolidation of resources facilitate efficient allocation. Targeted application of perioperative management strategies and surgical treatment plans maximize the provision of breast reconstructive services. CONCLUSIONS: A unified national approach to strategically reorganize healthcare delivery is feasible to uphold standards of patient-centered care for patients interested in breast reconstruction.

A Canadian national guideline on the neoadjuvant treatment of invasive breast cancer, including patient assessment, systemic therapy, and local management principles.

PURPOSE: The neoadjuvant treatment of breast cancer (NABC) is a rapidly changing area that benefits from guidelines integrating evidence with expert consensus to help direct practice. This can optimize patient outcomes by ensuring the appropriate use of evolving neoadjuvant principles. METHODS: An expert panel formulated evidence-based practice recommendations spanning the entire neoadjuvant breast cancer treatment journey. These were sent for practice-based consensus across Canada using the modified Delphi methodology, through a secure online survey. Final recommendations were graded using the GRADE criteria for guidelines. The evidence was reviewed over the course of guideline development to ensure recommendations remained aligned with current relevant data. RESULTS: Response rate to the online survey was almost 30%; representation was achieved from various medical specialties from both community and academic centres in various Canadian provinces. Two rounds of consensus were required to achieve 80% or higher consensus on 59 final statements. Five additional statements were added to reflect updated evidence but not sent for consensus. CONCLUSIONS: Key highlights of this comprehensive Canadian guideline on NABC include the use of neoadjuvant therapy for early stage triple negative and HER2 positive breast cancer, with subsequent adjuvant treatments for patients with residual disease. The use of molecular signatures, other targeted adjuvant therapies, and optimal response-based local regional management remain actively evolving areas. Many statements had evolving or limited data but still achieved high consensus, demonstrating the utility of such a guideline in helping to unify practice while further evidence evolves in this important area of breast cancer management.

Radiotherapy and radiosensitization in breast cancer: Molecular targets and clinical applications.

Relatively poor survival outcomes are observed in advanced or metastatic breast cancer, where local control of the primary or metastatic disease may be achieved by surgical resection, local ablative and radiation therapies. Radioresistance, poses a major challenge in achieving durable oncologic outcomes, mandating development of novel management strategies. Although multimodality approaches that combine radiotherapy with chemotherapy, or systemic agents, are utilized for radiosensitization and treatment of various malignancies, this approach has not yet found its clinical application in breast cancer. Some agents for breast cancer treatment can serve as radiosensitizers, creating an opportunity to enhance effects of radiation while providing systemic disease control. Hence, combination of radiotherapy with radiosensitizing agents have the potential to improve oncologic outcomes in advanced or metastatic breast cancer. This review discusses molecular targets for radiosensitization and novel systemic agents that have potential for clinical use as radiosensitizers in breast cancer.

Experiences and Perceptions of Older Adults with Lower-Risk Hormone Receptor-Positive Breast Cancer about Adjuvant Radiotherapy and Endocrine Therapy: A Patient Survey.

Older patients with lower-risk hormone receptor-positive (HR+) breast cancer are frequently offered both radiotherapy (RT) and endocrine therapy (ET) after breast-conserving surgery (BCS). A survey was performed to assess older patients' experiences and perceptions regarding RT and ET, and participation interest in de-escalation trials. Of the 130 patients approached, 102 eligible patients completed the survey (response rate 78%). The median age of respondents was 74 (interquartile range 71-76). Most participants (71%, 72/102) received both RT and ET. Patients felt the role of RT and ET, respectively, was to: reduce ipsilateral tumor recurrence (91%, 90/99 and 62%, 61/99) and improve survival (56%, 55/99 and 49%, 49/99). More patients had significant concerns regarding ET (66%, 65/99) than RT (39%, 37/95). When asked which treatment had the most negative effect on their quality of life, the results showed: ET (35%, 25/72), RT (14%, 10/72) or both (8%, 6/72). Participants would rather receive RT (57%, 41/72) than ET (43%, 31/72). Forty-four percent (44/100) of respondents were either, "not comfortable" or "not interested" in participating in potential de-escalation trials. Although most of the adjuvant therapy de-escalation trials evaluate the omission of RT, de-escalation studies of ET are warranted and patient centered.

Detection of Circulating Tumor DNA in Patients with Thyroid Nodules.

OBJECTIVE: Detection of circulating tumor DNA (ctDNA) in cancer patients can potentially serve as a noninvasive, sensitive test of disease status. The purpose of this study was to determine the ability to detect BRAF (V600E) mutations in the plasma of patients with thyroid nodules, with the goal of distinguishing between benign and malignant nodules. METHODS: Consecutive patients with thyroid nodules who consented for surgery were recruited. Plasma samples were obtained preoperatively and one month postoperatively. Quantitative PCR was used to determine the levels of the BRAF (V600E) mutation preoperatively and postoperatively. RESULTS: A total of 109 patients were recruited. On final pathology, 38 (32.8%) patients had benign thyroid nodules, 45 (38.8%) had classical papillary thyroid cancer (PTC), 23 (19.8%) had nonclassical PTC, and 3 (2.6%) had follicular thyroid cancer. 15/109 patients had detectable BRAF (V600E) ctDNA in their preoperative samples-all of them having classical PTC. Higher T-stage and extrathyroidal extension in PTC were associated with positive BRAF (V600E) ctDNA (p < 0.05). Eighty-eight pairs of preoperative and postoperative plasma samples were collected and analyzed. Of these eighty-eight paired samples, a total of 13/88 (14.8%) patients had detectable BRAF (V600E) ctDNA in their preoperative samples-all of them having classical PTC. 12 of these 13 patients had no detectable BRAF (V600E) postoperatively, while one remaining patient had a significant decline in his levels (p < 0.05). CONCLUSION: BRAF (V600E) circulating thyroid tumor DNA can be detected in plasma and is correlated with a final diagnosis of the classical variant of PTC. Given that a postoperative drop in BRAF (V600E) ctDNA levels was observed in all cases suggests its utility as a tumor marker.

Pri-miR526b and Pri-miR655 Are Potential Blood Biomarkers for Breast Cancer.

We reported that two microRNAs, miR526b and miR655, are oncogenic in breast cancer (BC). Overexpression of these two miRNAs in poorly metastatic BC cells promotes aggressive BC phenotypes in vitro and in vivo. High expression of each miRNA was associated with poor patient survival. In this pilot biomarker study, we report for the first time that miRNA precursor RNAs (pri-miRNAs) are robust and sensitive biomarkers for BC, detectable in both human blood plasma and biopsy tissues. Pri-miRNA detection and quantification do not require a special enrichment procedure, thus reducing specimen quantity. Blood plasma samples from 90 malignant tumor-bearing patients and 20 benign lesion-bearing participants (control) were analyzed for pri-miRNA expression with a quantitative real-time polymerase chain reaction. Results revealed that normalized expressions of plasma pri-miR526b and pri-miR655 are significantly upregulated in malignancy compared to benign plasmas (p = 0.002 and p = 0.03, respectively). Both pri-miRNAs showed more prominent results to distinguish stage I plasmas from benign plasmas (p = 0.001 for pri-miR526b and p = 0.0001 for pri-miR655). We have also validated pri-miRNA expression in independent tumor bank tissues, showing significant upregulation of both pri-miRNAs in BC; thus, pri-miRNAs are robust markers. The diagnostic relevance of pri-miRNAs was computed with the area under the curve (AUC). Pri-miR526b is a sensitive biomarker to distinguish cancer from control plasmas (sensitivity of 86%; AUC = 71.47%, p = 0.0027) with a positive predictive value of 88.89%; however, pri-miR655 did not show significant sensitivity. Furthermore, pri-miR526b could also significantly distinguish tumors as early as stage I from control (sensitivity of 75%; AUC = 72.71%, p = 0.0037). Therefore, pri-miR526b can be used as an early diagnostic biomarker. The expression of both pri-miRNAs was significantly high in ER-positive and HER2-negative subgroups of BC; hence, these biomarkers might play a role in the management of endocrine therapy designs. Additionally, with a case-control cohort study, we identified that high expression of pri-miR526b in the blood is also a risk factor associated with breast cancer (OR = 4.3, CI = 1.39-13.34, p = 0.01). Pri-miRNAs could be considered novel breast cancer blood biomarkers.

Management of the Axilla in Early-Stage Breast Cancer: Ontario Health (Cancer Care Ontario) and ASCO Guideline.

PURPOSE: To provide recommendations on the best strategies for the management and on the best timing and treatment (surgical and radiotherapeutic) of the axilla for patients with early-stage breast cancer. METHODS: Ontario Health (Cancer Care Ontario) and ASCO convened a Working Group and Expert Panel to develop evidence-based recommendations informed by a systematic review of the literature. RESULTS: This guideline endorsed two recommendations of the ASCO 2017 guideline for the use of sentinel lymph node biopsy in patients with early-stage breast cancer and expanded on that guideline with recommendations for radiotherapy interventions, timing of staging after neoadjuvant chemotherapy (NAC), and mapping modalities. Overall, the ASCO 2017 guideline, seven high-quality systematic reviews, 54 unique studies, and 65 corollary trials formed the evidentiary basis of this guideline. RECOMMENDATIONS: Recommendations are issued for each of the objectives of this guideline: (1) To determine which patients with early-stage breast cancer require axillary staging, (2) to determine whether any further axillary treatment is indicated for women with early-stage breast cancer who did not receive NAC and are sentinel lymph node-negative at diagnosis, (3) to determine which axillary strategy is indicated for women with early-stage breast cancer who did not receive NAC and are pathologically sentinel lymph node-positive at diagnosis (after a clinically node-negative presentation), (4) to determine what axillary treatment is indicated and what the best timing of axillary treatment for women with early-stage breast cancer is when NAC is used, and (5) to determine which are the best methods for identifying sentinel nodes.Additional information is available at www.asco.org/breast-cancer-guidelines.

Redefining postmastectomy radiation contouring in the era of immediate breast reconstruction: An accurate assessment of local recurrence risk.

INTRODUCTION: Most studies report post-mastectomy local recurrences as chest wall recurrences without clarifying whether the recurrence is in the subcutaneous tissue, muscle or underlying rib. Post-mastectomy chest wall radiation is recommended in patients at increased risk of locoregional recurrence. Chest wall radiation-related fibrosis has become an important clinical consideration in the era of immediate implant-based breast reconstruction. In patients with commonly performed subpectoral implant-based reconstruction, the pectoralis major becomes relocated anterior to the implant and just deep to skin, therefore raising the question of value in radiating deep chest wall structures. This study assessed the rate of recurrence in each anatomical region of chest wall in post-mastectomy patients. METHODS: A comprehensive breast cancer database of 4287 patients at a single regional cancer center from 2006 to 2018 was retrospectively analyzed to identify 1571 mastectomy patients. Recurrences were classified as local skin/subcutaneous, pectoralis muscle (pectoralis major), deep chest wall (pectoralis minor, intercostal muscle or rib) or regional axillary recurrence. RESULTS: A total of 26 patients with locoregional recurrence were identified. Most recurrences were in the skin/subcutaneous level. Of 1571 mastectomy patients, only one patient developed a local recurrence posterior to pectoralis major. Our literature search and meta-analysis revealed that local recurrences post-mastectomy are much more likely to be in subcutaneous tissues/pectoralis major versus deeper chest wall. CONCLUSION: A reduced clinical target volume which encompasses skin/subcutaneous and pectoralis muscle layers without treating deep chest wall may be more appropriate to reduce radiation-associated toxicity since avoiding circumferential radiation of an implant may prevent capsular contracture without compromising treatment benefit.

Intrafraction motion monitoring to determine PTV margins in early stage breast cancer patients receiving neoadjuvant partial breast SABR.

BACKGROUND AND PURPOSE: To quantify intra-fraction tumor motion using imageguidance and implanted fiducial markers to determine if a 5 mm planning-target-volume (PTV) margin is sufficient for early stage breast cancer patients receiving neoadjuvant stereotactic ablative radiotherapy (SABR). MATERIALS AND METHODS: A HydroMark© (Mammotome) fiducial was implanted at the time of biopsy adjacent to the tumor. Sixty-one patients with 62 tumours were treated prone using a 5 mm PTV margin. Motion was quantified using two methods (separate patient groups): 1) difference in 3D fiducial position pre- and post-treatment cone-beam CTs (CBCTs) in 18 patients receiving 21 Gy/1fraction (fx); 2) acquiring 2D triggered-kVimages to quantify 3D intra-fraction motion using a 2D-to-3D estimation method for 44 tumours receiving 21 Gy/1fx (n = 22) or 30 Gy/3fx (n = 22). For 2), motion was quantified by calculating the magnitude of intra-fraction positional deviation from the pretreatment CBCT. PTV margins were derived using van Herkian analysis. RESULTS: The average ± standard deviation magnitude of motion across patients was 1.3 ± 1.15 mm Left/Right (L/R), 1.0 ± 0.9 mm Inferiorly/Superiorly (I/S), and 1.8 ± 1.5 mm Anteriorly/Posteriorly (A/P). 85/105 (81%) treatment fractions had dominant anterior motion. 6/62patients (9.7%) had mean intra-fraction motion during any fraction > 5 mm in any direction, with 4 in the anterior direction. Estimated PTV margins for single and three-fx patients in the L/R, I/S, and A/P directions were 6.0x4.1x5.9 mm and 4.5x2.9x4.3 mm, respectively. CONCLUSION: Our results suggest that a 5 mm PTV margin is sufficient for the I/S and A/P directions if a lateral kV image is acquired immediately before treatment. For the L/R direction, either further immobilization or a larger margin is required.

Computational Radiology in Breast Cancer Screening and Diagnosis Using Artificial Intelligence.

Breast cancer screening has been shown to significantly reduce mortality in women. The increased utilization of screening examinations has led to growing demands for rapid and accurate diagnostic reporting. In modern breast imaging centers, full-field digital mammography (FFDM) has replaced traditional analog mammography, and this has opened new opportunities for developing computational frameworks to automate detection and diagnosis. Artificial intelligence (AI), and its subdomain of deep learning, is showing promising results and improvements on diagnostic accuracy, compared to previous computer-based methods, known as computer-aided detection and diagnosis.In this commentary, we review the current status of computational radiology, with a focus on deep neural networks used in breast cancer screening and diagnosis. Recent studies are developing a new generation of computer-aided detection and diagnosis systems, as well as leveraging AI-driven tools to efficiently interpret digital mammograms, and breast tomosynthesis imaging. The use of AI in computational radiology necessitates transparency and rigorous testing. However, the overall impact of AI to radiology workflows will potentially yield more efficient and standardized processes as well as improve the level of care to patients with high diagnostic accuracy.

Assessing the effect of a hands-on oncoplastic surgery training course: A survey of Canadian surgeons.

BACKGROUND: The adoption of oncoplastic surgery in North America is poor despite evidence supporting the benefits. Surgeons take courses to acquire oncoplastic techniques, however, the effect of these courses is unknown. This study aimed to assess the impact of a hands-on oncoplastic course on surgeons' comfort with oncoplastic techniques and rate of adoption of these techniques in their practice. MATERIAL AND METHODS: An online 10-question survey was developed and distributed to surgeons who had participated in a hands-on oncoplastic course offered in Ontario, Canada. Categorical data were reported using frequencies and percentages. RESULTS: A total of 105 surveys were sent out of which 69 attending surgeons responded (response rate: 65.7%). All respondents stated cosmesis was of the utmost importance in breast conserving surgery. The most common oncoplastic techniques they currently use included glandular re-approximation (98.4%), undermining of skin (93.6%), undermining of the nipple areolar complex (63.4%), and de-epithelialization and repositioning of the nipple areola complex (49.2%). Only 26% of respondnets stated they used more advanced techniques such as mammoplasty. Sixty percent of surgeons reported they used oncoplastic techniques in at least half of their cases. Ninety-two percent of respondents stated that the hands-on course increased the amount of oncoplastic techniques in their practice. At least 70% of respondents stated they would do another hands-on course. The main factor that facilitated the uptake of oncoplastic techniques was a better understanding of surgical techniques and planning. CONCLUSION: A hands-on oncoplastic course helps surgeons adopt oncoplastic surgery techniques into their clinical practice. This teaching model allows surgeons to become comfortable with a variety of techniques. This study supports the relevance of a hands-on oncoplastic course to enhance the availability of safe oncoplastic surgery for breast cancer patients.

Structured-light surface scanning system to evaluate breast morphology in standing and supine positions.

Breast shapes are affected by gravitational loads and deformities. Measurements obtained in the standing position may not correlate well with measurements in the supine position, which is more representative of patient position during breast surgery. A dual color 3D surface imaging system capable of scanning patients in both supine and standing positions was developed to evaluate the effect of changes in body posture on breast morphology. The system was evaluated with  breast phantoms to assess accuracy, then tested on ten subjects in three body postures to assess its effectiveness as a clinical tool. The accuracy of the system was within 0.4 mm on average across the model. For the human study, there was no effect of body posture on breast volumes (p value > 0.05), but we observed an effect of completeness of breast scans on body posture (p value < 0.05). Post-hoc tests showed that the supine position and the standing position with hands at the waist differed significantly (p value < 0.05). This study shows that the system can quantitatively evaluate the effect of subject postures, and thereby has the potential to be used to investigate peri-operative changes in breast morphology.