International multidisciplinary consensus on the integration of radiotherapy with new systemic treatments for breast cancer: European Society for Radiotherapy and Oncology (ESTRO)-endorsed recommendations.

Novel systemic therapies for breast cancer are being rapidly implemented into clinical practice. These drugs often have different mechanisms of action and side-effect profiles compared with traditional chemotherapy. Underpinning practice-changing clinical trials focused on the systemic therapies under investigation, thus there are sparse data available on radiotherapy. Integration of these new systemic therapies with radiotherapy is therefore challenging. Given this rapid, transformative change in breast cancer multimodal management, the multidisciplinary community must unite to ensure optimal, safe, and equitable treatment for all patients. The aim of this collaborative group of radiation, clinical, and medical oncologists, basic and translational scientists, and patient advocates was to: scope, synthesise, and summarise the literature on integrating novel drugs with radiotherapy for breast cancer; produce consensus statements on drug-radiotherapy integration, where specific evidence is lacking; and make best-practice recommendations for recording of radiotherapy data and quality assurance for subsequent studies testing novel drugs.

A BRILLIANT-BRCA study: residual breast tissue after mastectomy and reconstruction.

INTRODUCTION: Different types of mastectomies leave different amounts of residual breast tissue. The significance of the residual breast volume (RBV) is not clear. Therefore, we developed an MRI tool that allows to easily assess the RBV. In this study we evaluated factors associated with RBV after skin or nipple sparing mastectomy (SSM/NSM) in breast cancer BRCA pathogenic variant (PV) carriers who underwent both therapeutic and risk reducing SSM/NSM and its relation to breast cancer outcomes using an innovative MRI-based tool. METHODS: Data of breast cancer BRCA PV who were treated between 2006 and 2020 were retrieved from of the oncogenetics unit databases. Only patients who underwent SSM/NSM and had a postoperative breast MRI available for analysis were included. Data collected included demographics, clinicopathological features, and outcomes. The MRI tool was developed by a breast cancer imaging laboratory. A logistic regression test and 95% confidence interval (CI) were used to assess the associated risk of increased RBV. A forward stepwise linear regression was used to correlate tumour-patient specific factors and RBV, and a Kaplan-Meier curve to show the probability of locoregional relapse. RESULTS: A total of 84 patients undergoing 89 mastectomies were included. At a median follow-up of 98 months, 5 local, 2 regional, and 4 distant recurrences were observed. RBV was not significantly related with breast cancer outcomes (p value = NS). A higher body mass index (BMI) was associated with a higher RBV (p < 0.0001). A larger number of involved axillary nodes was associated with a smaller RBV (p = 0.025). The RBV on the risk-reducing mastectomy side was significantly higher compared to the breast cancer side (p value = 0.007). Local recurrences occurred in the vicinity of the primary tumour.

Optimising of axillary therapy in breast cancer: lessons from the past to plan for a better future.

In this narrative review, we aim to explore the ability of radiation therapy to eradicate breast cancer regional node metastasis. It is a journey through data of older trials without systemic therapy showing the magnitude of axillary therapy (surgery versus radiation) on cancer control. Considering that both systemic and loco-regional therapies were shown to reduce any recurrence with a complex interaction, our review includes surgical, radiation, and radiobiology consideration for breast cancer, and provide our view of future practise. The aim is to provide information optimise radiation therapy in the era of primary systemic therapy.

Designing clinical trials based on modern imaging and metastasis-directed treatments in patients with oligometastatic breast cancer: a consensus recommendation from the EORTC Imaging and Breast Cancer Groups.

Breast cancer remains the most common cause of cancer death among women. Despite its considerable histological and molecular heterogeneity, those characteristics are not distinguished in most definitions of oligometastatic disease and clinical trials of oligometastatic breast cancer. After an exhaustive review of the literature covering all aspects of oligometastatic breast cancer, 35 experts from the European Organisation for Research and Treatment of Cancer Imaging and Breast Cancer Groups elaborated a Delphi questionnaire aimed at offering consensus recommendations, including oligometastatic breast cancer definition, optimal diagnostic pathways, and clinical trials required to evaluate the effect of diagnostic imaging strategies and metastasis-directed therapies. The main recommendations are the introduction of modern imaging methods in metastatic screening for an earlier diagnosis of oligometastatic breast cancer and the development of prospective trials also considering the histological and molecular complexity of breast cancer. Strategies for the randomisation of imaging methods and therapeutic approaches in different subsets of patients are also addressed.

Current clinical practice in the management of phyllodes tumors of the breast: an international cross-sectional study among surgeons and oncologists.

PURPOSE: Phyllodes tumors of the breast are rare fibroepithelial lesions that are classified as benign, borderline or malignant. There is little consensus on best practice for the work-up, management, and follow-up of patients with phyllodes tumors of the breast, and evidence-based guidelines are lacking. METHODS: We conducted a cross-sectional survey of surgeons and oncologists with the aim to describe current clinical practice in the management of phyllodes tumors. The survey was constructed in REDCap and distributed between July 2021 and February 2022 through international collaborators in sixteen countries across four continents. RESULTS: A total of 419 responses were collected and analyzed. The majority of respondents were experienced and worked in a university hospital. Most agreed to recommend a tumor-free excision margin for benign tumors, increasing margins for borderline and malignant tumors. The multidisciplinary team meeting plays a major role in the treatment plan and follow-up. The vast majority did not consider axillary surgery. There were mixed opinions on adjuvant treatment, with a trend towards more liberal regiments in patients with locally advanced tumors. Most respondents preferred a five-year follow-up period for all phyllodes tumor types. CONCLUSIONS: This study shows considerable variation in clinical practice managing phyllodes tumors. This suggests the potential for overtreatment of many patients and the need for education and further research targeting appropriate surgical margins, follow-up time and a multidisciplinary approach. There is a need to develop guidelines that recognize the heterogeneity of phyllodes tumors.

Variations in Practice and Geographic Disparities Between Dedicated Multidisciplinary Clinics for BRCA1/BRCA2 Mutation Carriers in Israel.

BACKGROUND: Population screening for the BRCA mutations in Ashkenazi Jewish women was recently implemented in Israel and is expected to lead to a 10-fold increase in the diagnosis of asymptomatic carriers. Performing the screening follow-up within multidisciplinary dedicated clinics for carriers is recommended for early detection and risk reduction. OBJECTIVES: : To determine the availability, capacity, and practices of dedicated screening clinic for BRCA carriers in Israel. METHODS: A telephone-based survey of all public hospitals in Israel was conducted October 2020 to August 2021 to determine whether they had a dedicated clinic. Dedicated clinics were defined as multidisciplinary screening clinics offering at least breast and gynecological screening and risk reducing services on site. The clinic director or nurse navigator answered a questionnaire about screening practices followed by a semi-structured interview. RESULTS: Of the ten dedicated BRCA clinics found in Israel, nine participated. Approximately 4500 BRCA carriers are currently being followed. No specialized clinics are available in the southern district or in the northernmost half of the northern district of Israel, leading to a disparity between periphery and center. Screening recommendations, although asserted as adhering to international guidelines, vary among clinics including age at initiating of clinical exam, use of adjunct imaging modalities, and follow-up during lactation and after risk reducing surgery. CONCLUSIONS: There is a suboptimal distribution of dedicated clinics for BRCA carriers in Israel. Nationally centralized attempt to create guidelines that will unify screening practices is warranted, especially considering the expected increase in demand.

European Society for Radiotherapy and Oncology Advisory Committee in Radiation Oncology Practice consensus recommendations on patient selection and dose and fractionation for external beam radiotherapy in early breast cancer.

High-quality randomised clinical trials testing moderately fractionated breast radiotherapy have clearly shown that local control and survival is at least as effective as with 2 Gy daily fractions with similar or reduced normal tissue toxicity. Fewer treatment visits are welcomed by patients and their families, and reduced fractions produce substantial savings for health-care systems. Implementation of hypofractionation, however, has moved at a slow pace. The oncology community have now reached an inflection point created by new evidence from the FAST-Forward five-fraction randomised trial and catalysed by the need for the global radiation oncology community to unite during the COVID-19 pandemic and rapidly rethink hypofractionation implementation. The aim of this paper is to support equity of access for all patients to receive evidence-based breast external beam radiotherapy and to facilitate the translation of new evidence into routine daily practice. The results from this European Society for Radiotherapy and Oncology Advisory Committee in Radiation Oncology Practice consensus state that moderately hypofractionated radiotherapy can be offered to any patient for whole breast, chest wall (with or without reconstruction), and nodal volumes. Ultrafractionation (five fractions) can also be offered for non-nodal breast or chest wall (without reconstruction) radiotherapy either as standard of care or within a randomised trial or prospective cohort. The consensus is timely; not only is it a pragmatic framework for radiation oncologists, but it provides a measured proposal for the path forward to influence policy makers and empower patients to ensure equity of access to evidence-based radiotherapy.

European Society for Radiotherapy and Oncology and European Organisation for Research and Treatment of Cancer consensus on re-irradiation: definition, reporting, and clinical decision making.

Re-irradiation can be considered for local recurrence or new tumours adjacent to a previously irradiated site to achieve durable local control for patients with cancer who have otherwise few therapeutic options. With the use of new radiotherapy techniques, which allow for conformal treatment plans, image guidance, and short fractionation schemes, the use of re-irradiation for different sites is increasing in clinical settings. Yet, prospective evidence on re-irradiation is scarce and our understanding of the underlying radiobiology is poor. Our consensus on re-irradiation aims to assist in re-irradiation decision making, and to standardise the classification of different forms of re-irradiation and reporting. The consensus has been endorsed by the European Society for Radiotherapy and Oncology and the European Organisation for Research and Treatment of Cancer. The use of this classification in daily clinical practice and research will facilitate accurate understanding of the clinical implications of re-irradiation and allow for cross-study comparisons. Data gathered in a uniform manner could be used in the future to make recommendations for re-irradiation on the basis of clinical evidence. The consensus document is based on an adapted Delphi process and a systematic review of the literature was done according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA).

Axillary surgery after neoadjuvant therapy in initially node-positive breast cancer: international EUBREAST survey.

BACKGROUND: There is no consensus on axillary management after neoadjuvant therapy (NAT) in patients with clinically node-positive (cN+) breast cancer. To investigate current clinical practice, an international survey was conducted among breast surgeons and radiation oncologists. The aim of the first part of the survey was to provide a snapshot of international discrepancies regarding axillary surgery in this context. METHODS: The European Breast Cancer Research Association of Surgical Trialists (EUBREAST) developed a web-based survey containing 39 questions describing clinical scenarios in the setting of axillary management in patients with cN1 disease converting to ycN0 after NAT. The survey was then distributed to breast surgeons and radiation oncologists via 14 breast cancer societies between April and October 2021. RESULTS: Responses from 349 physicians in 45 countries were recorded. The most common post-NAT axillary surgery in patients with cN1 disease converting to ycN0 was targeted axillary dissection (54.2 per cent), followed by sentinel lymph node biopsy (SLNB) alone (20.9 per cent), level 1-2 axillary lymph node dissection (ALND) (18.4 per cent), level 1-3 ALND (4 per cent), and targeted lymph node biopsy (2.5 per cent). For SLNB alone, dual tracers were most commonly used (62.3 per cent). Management varied widely in patients with ambiguous axillary status before initiation of treatment or a residual metastatic burden in the axilla after NAT. In patients with ycN+ tumours, ALND was the preferred surgical approach for 66.8 per cent of respondents. CONCLUSION: These results highlight the wide heterogeneity in surgical approaches to the axilla after NAT. To standardize the guidelines, further data from clinical research are urgently needed, which underlines the importance of the ongoing AXSANA (EUBREAST-3) study.

Ductal Carcinoma In Situ (DCIS) Diagnosed by MRI-Guided Biopsy among BRCA1/BRCA2 Mutation Carriers.

Background: While BRCA1/BRCA2 pathogenic sequence variants (PSVs) clearly confer an increased risk for invasive breast cancer, the extent to which these mutant alleles increase DCIS risk is less clear. Objective: To assess the rate of detection over a 5-year period, and MRI imaging features of pure noncalcified DCIS in a cohort of Israeli BRCA1/BRCA2 PSV carriers attending a high-risk clinic from 2015 to 2020. Materials and Methods: All female BRCA1/BRCA2 PSV-carriers followed at the Meirav High-risk clinic from 2015 to 2020 were eligible if they underwent semiannual breast imaging (MRI/mammography) and MRI-guided biopsy-proven pure DCIS. Clinical data, pathology information, and imaging characteristics were retrieved from the computerized archiving system. Results: 18/121 (15.2%) participating BRCA1 PSV carriers and 8/81 (10.1%) BRCA2 PSV-carriers who underwent MRI-guided biopsy were diagnosed with DCIS. The median age of BRCA1 carriers and BRCA2 carriers was 49.8 years and 60.6 years, respectively (p = 0.55). Negative estrogen-receptor tumors were diagnosed in 13/18 (72%) BRCA1 and 2/8 (25%) BRCA2 PSV carriers (p < 0.05). Thirteen (13/18-72%) BRCA1 carriers had intermediate to high-grade or high-grade DCIS compared with 4/8 (50%) of BRCA2 carriers (p = 0.03). Over the 5-year study period, 29/1100 (2.6%) BRCA1/BRCA2 PSV carriers were diagnosed with DCIS seen on MRI only. Conclusion: MRI-detected noncalcified DCIS is more frequent in BRCA1 PSV carriers compared with BRCA2 carriers, unlike the BRCA2 predominance in mammography-detected calcified DCIS. BRCA1-related DCIS is diagnosed earlier, more likely to be estrogen receptor-negative and of higher grade compared with BRCA2-related DCIS. Future prospective studies should validate these results and assess the actual impact they might have on clinical management of BRCA PSV carriers.

Post-mastectomy surveillance of BRCA1/BRCA2 mutation carriers: Outcomes from a specialized clinic for high-risk breast cancer patients.

Female BRCA1/BRCA2 mutation carriers may elect bilateral risk-reducing mastectomy. There is a paucity of data on yield of imaging surveillance after risk-reducing mastectomy. This retrospective study focused on female BRCA1/BRCA2 mutation carriers who underwent bilateral mastectomy either as primary preventative, or as secondary preventative, after breast cancer diagnosis. All participants underwent breast imaging at 6- to 12-month intervals after mastectomy. Data on subsequent breast cancer diagnosis and timing were collected and compared between the groups. Overall, 184 female mutation carriers (134 BRCA1, 45 BRCA2, 5 both BRCA genes) underwent bilateral mastectomy after initial breast cancer diagnosis, between April 1, 2009 and August 31, 2018. During a mean follow-up of 6.2 ± 4.2 years, 13 (7.06%) were diagnosed with breast cancer; 12 ipsilateral (range: 0.4-28.8 years) and 1 contralateral breast cancer, 15.9 years after surgery. On the contrary, among asymptomatic BRCA1 (n = 40) and BRCA2 (n = 13) mutation carriers who underwent primary risk-reducing mastectomy (mean age at surgery 39.5 ± 8.4 years); none has developed breast cancer after a mean follow-up of 5.4 ± 3.4 years. BRCA1/BRCA2 mutation carriers with prior disease who underwent risk-reducing mastectomy after breast cancer diagnosis are still prone for developing ipsi or contralateral breast cancer, and therefore may benefit from continues clinical and imaging surveillance, unlike BRCA1/BRCA2 mutation carriers who undergo primary preventative bilateral mastectomy.

COVID-RO study: the radiation oncology practice at times of COVID-19 outbreak - international survey.

BACKGROUND: Radiation therapy (RT), an essential treatment of cancer, involves multiple hospital visits. We hypothesized that radiation departments would adjust their work patterns and RT protocols in response to the SARS-CoV-2 pandemic. MATERIALS AND METHODS: An electronic survey was sent during April 2020 to an international sample of radiation oncologists. The survey explored various aspects of departmental preparedness, and changes to their institutional RT protocols. RESULTS: A total of 68 radiation oncologists from 13 countries answered the survey. Healthcare systems were at least moderately affected in 76%. Most institutes appeared well prepared for the outbreak: regarding the availability of personal protective equipment, tests, and telemedicine/videoconference facilities. Screening for SARS-CoV-2 was applied in 59% of responders. Modification of RT protocols were minor in 66%, significant in 19% and no changes made in 15%. The extent to which protocols were modified correlated with overall healthcare disruption (p = 0.028). Normal fractionation was recommended to continue in 83% and 85% of head & neck, and cervical cancers vs. 64% of lung cancers (p = 0.001).In case the pandemic worsens, there was strong agreement to prioritize RT for aggressive cancers (80%), delay RT for slow-growing tumors (78%) and change to evidance-based hypofractionations protocols (79.4%). The option of delayed/omitted adjuvant RT (not site specific) was selected in 47%. CONCLUSION: This international survey concludes that, by making significant organizational adjustments and minor protocol modifications, RT may be safely continued during this pandemic. If the crisis worsens, there was strong agreement to continue the treatment of aggressive tumors and utilize evidence-based hypofractionated protocols.

PSMA PET/CT to evaluate response to SBRT for prostate cancer bone metastases.

BACKGROUND: In the current study we evaluated 68Ga PSMA PET/ CT to measure local control of bone metastasis in oligometastatic prostate cancer patients treated with SBRT. MATERIALS AND METHODS: After the institutional review board approval, a retrospective review of medical records of consecutive prostate cancer patients treated between 2014 and 2018 was conducted. Only medical records of patients that were treated with SBRT for bone metastasis and had pre-and post-SBRT 68Ga PSMA PET/CT scans were included in our study. Data extracted from the medical files included patient-related (age), disease-related (Gleason score, site of metastasis), and treatment-related factors and outcomes. RESULTS: During the study period, a total of 12 patients (15 lesions) were included, with a median age of 73 years. The median follow-up was 26.5 months (range 13-45 months). Median time of 68Ga PSMA PET/ CT follow up was 17.0 months (range 3-39 months). The median pre-treatment PSA was 2 ng/mL (range 0.56-44 ng/mL) vs. post treatment PSA nadir of 0.01 ng/mL (0.01-4.32) with a median time to nadir of 7 months (range, 2-12). Local control was 93% during the follow up period and there was correlation with PS MA avidity on PE T. None patients developed recurrences in the treated bone. None of the patients had grade 3 or more toxicities during follow-up. CONCLUSIONS: SBRT is a highly effective and safe method for treatment of prostate cancer bone metastases. More studies are required to determine if SBRT provides greater clinical benefit than standard fractionation for oligometastatic prostate cancer patients. 68Ga PSMA PET/CT should be further investigated for delineation and follow-up.

Treatment after progression in the era of immunotherapy.

Immunotherapy represents a paradigm shift in oncology treatment. The goal of immunotherapy is to overcome immunosuppression induced by a tumour and its microenvironment, thereby allowing the immune system to target and kill cancer cells. The immunotherapy era began when the first immune checkpoint inhibitor, ipilimumab, was approved for use almost a decade ago. This therapeutic approach is associated with distinct types of response, including processes such as pseudoprogression (ie, increased tumour burden via radiology, which is not accompanied by clinical deterioration) and hyperprogression (ie, rapid progression of the disease as a result of immunotherapy). In this Review, we focus on therapeutic approaches for patients who progress on immunotherapy. We review the different types of clinical responses associated with immunotherapy and describe treatment options for this population.

Spatial location of local recurrences after mastectomy: a systematic review.

PURPOSE: We performed a systematic review to document the spatial location of local recurrences (LR) after mastectomy. METHODS: A PubMed search was conducted in August 2019 for the following terms: breast [Title/Abstract] AND cancer [Title/Abstract] AND recurrence [Title/Abstract] AND mastectomy [Title/Abstract]. The search was filtered for English language. Exclusion criteria included studies that did not specify the LR location or studies reporting LR associated with inflammatory breast cancer, or other breast cancers such as phyllodes tumours, lymphoma or associated with sarcoma/angiosarcoma. RESULTS: A total of 3922 titles were identified, of which 21 publications were eligible for inclusion in the final analysis. A total of 6901 mastectomy patients were included (range 25-1694). The mean LR proportion was 3.5%. Among the total of 351 LR lesions, 81.8% were in the subcutaneous tissue and the skin, while 16% were pectoral muscle recurrences. CONCLUSION: Local recurrences are mostly located within the subcutaneous tissue and the skin, assumed to result from unrecognized/subclinical tumour foci left behind after mastectomy, surgical implantation of tumour cells in the wound/scar and/or tumour emboli within the subcutaneous lymphatics. Pectoral muscle recurrences are less frequent and may be attributed to residual disease along the posterior surgical margin and/or lymphatic involvement.

Residual Glandular Breast Tissue After Mastectomy: A Systematic Review.

BACKGROUND: The goal of mastectomy is remove all of the glandular breast tissue (BGT) without compromising skin flaps viability. The purpose of this systematic review was to localize and/or estimate the amount of residual BGT (rBGT) after mastectomy and to identify factors that could be related to rBGT and/or residual disease. METHODS: We conducted a PubMed search. The report was subdivided according to the method used to evaluate the presence of rBGT. A total of 16 publications were included in our final report. Two main methods for identifying rBGT included imaging (i.e., MRI scan) and histological evaluation at the time of mastectomy. RESULTS: The rate of rBGT was reported in up to 100% of the patients and was found to be associated mainly with the type of surgical resection, indication, and surgeon's expertise. Residual breast tissue can be found in all areas of the remaining chest wall, mostly in the skin-flaps, and more frequently underneath the nipple-areola complex.

Evaluation of a commercial DIR platform for contour propagation in prostate cancer patients treated with IMRT/VMAT.

PURPOSE: To assess the performance and limitations of contour propagation with three commercial deformable image registration (DIR) algorithms using fractional scans of CT-on-rails (CTOR) and Cone Beam CT (CBCT) in image guided prostate therapy patients treated with IMRT/VMAT. METHODS: Twenty prostate cancer patients treated with IMRT/VMAT were selected for analysis. A total of 453 fractions across those patients were analyzed. Image data were imported into MIM (MIM Software, Inc., Cleveland, OH) and three DIR algorithms (DIR Profile, normalized intensity-based (NIB) and shadowed NIB DIR algorithms) were applied to deformably register each fraction with the planning CT. Manually drawn contours of bladder and rectum were utilized for comparison against the DIR propagated contours in each fraction. Four metrics were utilized in the evaluation of contour similarity, the Hausdorff Distance (HD), Mean Distance to Agreement (MDA), Dice Similarity Coefficient (DSC), and Jaccard indices. A subfactor analysis was performed per modality (CTOR vs. CBCT) and time (fraction). Point estimates and 95% confidence intervals were assessed via a Linear Mixed Effect model for the contour similarity metrics. RESULTS: No statistically significant differences were observed between the DIR Profile and NIB algorithms. However, statistically significant differences were observed between the shadowed NIB and NIB algorithms for some of the DIR evaluation metrics. The Hausdorff Distance calculation showed the NIB propagated contours vs. shadowed NIB propagated contours against the manual contours were 14.82 mm vs. 8.34 mm for bladder and 15.87 mm vs. 11 mm for rectum, respectively. Similarly, the Mean Distance to Agreement calculation comparing the NIB propagated contours vs. shadowed NIB propagated contours against the manual contours were 2.43 mm vs. 0.98 mm for bladder and 2.57 mm vs. 1.00 mm for rectum, respectively. The Dice Similarity Coefficients comparing the NIB propagated contours and shadowed NIB propagated contours against the manual contours were 0.844 against 0.936 for bladder and 0.772 against 0.907 for rectum, respectively. The Jaccard indices comparing the NIB propagated contours and shadowed NIB propagated contours against the manual contours were 0.749 against 0.884 for bladder and 0.637 against 0.831 for rectum, respectively. The shadowed NIB DIR, which showed the closest agreement with the manual contours performed significantly better than the DIR Profile in all the comparisons. The OAR with the greatest agreement varied substantially across patients and image guided radiation therapy (IGRT) modality. Intra-patient variability of contour metric evaluation was insignificant across all the DIR algorithms. Statistical significance at α = 0.05 was observed for manual vs. deformably propagated contours for bladder for all the metrics except Hausdorff Distance (P = 0.01 for MDA, P = 0.02 for DSC, P = 0.01 for Jaccard), whereas the corresponding values for rectum were: P = 0.03 for HD, P = 0.01 for MDA, P < 0.01 for DSC, P < 0.01 for Jaccard. The performance of the different metrics varied slightly across the fractions of each patient, which indicates that weekly contour propagation models provide a reasonable approximation of the daily contour propagation models. CONCLUSION: The high variance of Hausdorff Distance across all automated methods for bladder indicates widely variable agreement across fractions for all patients. Lower variance across all modalities, methods, and metrics were observed for rectum. The shadowed NIB propagated contours were substantially more similar to the manual contours than the DIR Profile or NIB contours for both the CTOR and CBCT imaging modalities. The relationship of each algorithm to similarity with manual contours is consistent across all observed metrics and organs. Screening of image guidance for substantial differences in bladder and rectal filling compared with the planning CT reference could aid in identifying fractions for which automated DIR would prove insufficient.

Effect of internal mammary vessels radiation dose on outcomes of free flap breast reconstruction.

To assess the impact of internal mammary (IM) vessels radiation dose on autologous free-flap based breast reconstruction outcomes. We retrospectively evaluated the medical records of breast cancer patients who underwent mastectomy and free-flap breast reconstruction after postoperative radiation therapy (RT) to the breast/chest wall with (n = 9) or without (n = 11) electively including the IM lymph nodes. Twenty patients were included. Median age at diagnosis was 50 years (range, 33-63). The median time interval between the start of RT and reconstructive surgery was 16 months (range, 6-45). The maximal IM vessels dose was not associated with the risk of all complications (P = 0.44) or fat necrosis (P = 0.31). The mean IM vessels dose was not significant for the risk of all complications (P = 0.13) but was significant for fat necrosis (P = 0.04). A high mean IM vessels dose was related to the occurrence of fat necrosis.

Precision medicine in head and neck cancer.

Head and Neck cancer is among the most common cancers worldwide, with a high prevalence in south East Asia, Brazil and central Europe. Head and Neck Squamous cell carcinoma (HNSCC) is associated with elevated mutational load but lacks specific genetic mutations. Exposure to carcinogens including tobacco and alcohol are the most dominant etiologic factors of HNSCC, while Epstein-Barr (HBV) and Human Papilloma Viruses (HPV) are associated with nasopharyngeal and oropharyngeal carcinoma, respectively. Surgery including open and minimally invasive procedures is considered the standard of care for the majority of oral cavity and early larynx cancers, while radiation therapy or concurrent chemoradiation are used for the other head and neck cancers. The treatment of patients with head and neck cancer is complex and has undergone considerable transformation in the last decade. These modalities include immunotherapy, targeted therapy (small molecule inhibitors or antibodies), or combined modality treatments. Emerging evidence supports a vital role of the immune system in eradicating HNSCC. Cancer cells express programmed death ligand 1 or 2 (PD-L1/2) which binds to the PD receptor on the T-cell, leading to an inactivation of the cytotoxic response of the T-cell. Cytotoxic T lymphocytes antigen-4 (CTLA-4) is another key player, expressed by cancer-activated T-cells, which binds to B7 ligand on the cancer cells, leading to inhibition of T-cells activation. Checkpoint inhibitors such as anti-PD-1 and anti-PD-L1 antibodies, were shown to significantly improve disease free survival and overall survival after failure of platinum-based chemotherapy. In addition, expression of HPV is associated with better response to single modality treatment (e.g. radiotherapy or surgery) and improved survival. In future years we expect to see the establishment of precision medicine modalities in an attempt to extend survival and improve quality of life of advanced stage HNSCC patients. Several phase III clinical trials are in progress to evaluate the utility of checkpoint inhibitors at different treatment settings, including combinations with adjuvant surgery, radiation therapy and chemotherapy.