Radiotherapy In Treatment Of Cancer Research Articles

Exodontia atraumática associada a elásticos ortodônticos em pacientes submetidos ao tratamento oncológico radioterápico: revisão de literatura

Introduction: Cancer is currently among the five most common causes of death worldwide, resulting from harmful habits or genetic predisposition. Oral cancer plays a major role in this scenario and requires special dental care due to the association of tooth loss with cancer treatment. Aim: This study aimed at the biological analysis of the processes triggered by radiotherapy treatment and presentation of an alternative method for safe tooth extraction in cancer patients. Literature review: Cancer radiotherapy treatment triggers a series of oral complications that will eventually require tooth extraction, for example, osteoradionecrosis, hyposalivation, caries, and periodontal disease. Discussion: Tooth extraction with orthodontic elastics involves the tooth at the cervical height with elastics allowing a slow, gradual, and less traumatic exfoliation of the root; this process takes approximately 5 to 8 weeks. This technique is associated with a good postoperative recovery and ensures adequate healing, significantly increasing the likelihood of a positive prognosis. Conclusion: These techniques are safe and decrease the risk of postoperative complications, thus ensuring recovery without major problems for the patient.

Evaluation of second cancer risks in breast cancer case of Regional Center of Oncology, Agadir

The aim of this study was to evaluate secondary cancer incidence (Excess Relative Risk (ERR)) and mortality incidence (Excess Absolute Risk (EAR)) during conformal radiotherapy treatment of breast cancer. Twenty-four patients with breast cancer treated with a mono-isocentric, three-dimensional conformal radiotherapy technique were studied. The ERR and EAR were calculated using the International Commission on Radiological Protection (ICRP) risk models. The results obtained are significantly higher than those estimated by previous studies; this confirms thus the need to improve the training of health professionals involved in the management of patients.

P69 - Relationships between bladder volumes in prostate cancer radiotherapy treatment with dose tracking

P69 - Relationships between bladder volumes in prostate cancer radiotherapy treatment with dose tracking

OD16 - Dosimetric impact of intrafraction motion during moderate hypo-fractionated prostate cancer radiotherapy treatment

OD16 - Dosimetric impact of intrafraction motion during moderate hypo-fractionated prostate cancer radiotherapy treatment

Automatic segmentation of the clinical target volume and organs at risk for rectal cancer radiotherapy using structure-contextual representations based on 3D high-resolution network

Radiotherapy is a cancer treatment that uses high doses of radiation to kill cancer cells. Segmentation of the clinical target volumes (CTVs) and organs at risk (OARs) is an essential step in rectal cancer radiotherapy treatment planning. However, the manual segmentation of CTVs and OARs is labor-intensive and prone to intra- and inter-rater variations. The challenge of this task lies in large shape variations and low-contrast structure boundary for some structures like intestine. The contextual information is very important to handle this challenge. Recently, deep learning has greatly improved the state-of-the-art results in automatic segmentation of anatomical structures including OARs and CTVs. However, existing approaches barely take advantages of relations among anatomical structures as contextual information, which limits the segmentation accuracy. In this study, we propose a novel structure-contextual representations approach based on 3D high-resolution network (3D HRNet-SCR) for segmentation of OARs and CTV of rectal cancer. First, we design a structure-contextual representation module (SCR) which could compute the representation for each structure of interest by aggregating the representations of voxels inside the structure and enhance the feature representation of each voxel with learned structure-contextual representations. Second, we extend the powerful 2D HRNet for semantic segmentation to 3D paradigm to better capture the contextual information across slices of volumetric data. Our propose approach integrates the proposed SCR module on top of the 3D HRNet to form a high-performance segmentation framework. Finally, we collect a large-scale rectal cancer dataset of 536 CT scans (total 64320 slices) for evaluation. Our proposed framework is extensively tested on this self-collected dataset, showing superiority compared with state-of-the-art OARs and CTV segmentation methods for rectal cancer treatment.

Comparison between two breast cancer treatment techniques by the external radiotherapy

The main objective of this study was to compare the mono-isocentric technique (MIT) with the skin-source distance (SSD) technique during radiotherapy breast cancer treatment. The results obtained show that the total number of Monitor Unit (MU) is always lower in MIT. The irradiation of target volumes was significantly improved with the MIT compared to the SSD technique, as well as the homogeneity of the dose distribution. The protection of organs at risk was significantly better with MIT. This study showed that MIT is better than SSD technique; we recommend its implementation in clinical practice for breast cancer radiotherapy treatment.

Deep learning-based auto-segmentation of clinical target volumes for radiotherapy treatment of cervical cancer.

ObjectivesBecause radiotherapy is indispensible for treating cervical cancer, it is critical to accurately and efficiently delineate the radiation targets. We evaluated a deep learning (DL)‐based auto‐segmentation algorithm for automatic contouring of clinical target volumes (CTVs) in cervical cancers.MethodsComputed tomography (CT) datasets from 535 cervical cancers treated with definitive or postoperative radiotherapy were collected. A DL tool based on VB‐Net was developed to delineate CTVs of the pelvic lymph drainage area (dCTV1) and parametrial area (dCTV2) in the definitive radiotherapy group. The training/validation/test number is 157/20/23. CTV of the pelvic lymph drainage area (pCTV1) was delineated in the postoperative radiotherapy group. The training/validation/test number is 272/30/33. Dice similarity coefficient (DSC), mean surface distance (MSD), and Hausdorff distance (HD) were used to evaluate the contouring accuracy. Contouring times were recorded for efficiency comparison.ResultsThe mean DSC, MSD, and HD values for our DL‐based tool were 0.88/1.32 mm/21.60 mm for dCTV1, 0.70/2.42 mm/22.44 mm for dCTV2, and 0.86/1.15 mm/20.78 mm for pCTV1. Only minor modifications were needed for 63.5% of auto‐segmentations to meet the clinical requirements. The contouring accuracy of the DL‐based tool was comparable to that of senior radiation oncologists and was superior to that of junior/intermediate radiation oncologists. Additionally, DL assistance improved the performance of junior radiation oncologists for dCTV2 and pCTV1 contouring (mean DSC increases: 0.20 for dCTV2, 0.03 for pCTV1; mean contouring time decrease: 9.8 min for dCTV2, 28.9 min for pCTV1).ConclusionsDL‐based auto‐segmentation improves CTV contouring accuracy, reduces contouring time, and improves clinical efficiency for treating cervical cancer.

Technologies to reduce radiation toxicity in prostate cancer patients: spacers - a simple and effective solution

The basic principles of the treatment of prostate cancer patients have underwent significant revisions in recent years. Modern radiotherapy techniques, which have demonstrated high efficacy and safety in long-term randomized trials, are beginning to take a leading position in the treatment of prostate cancer in an overwhelming number of clinical scenarios (National Comprehensive Cancer Network, 2021). Despite the obvious successes of radiation oncology, a number of important problems remain unresolved, first of all - the need to reduce the rates of radiation complications. The topographical anatomy of the prostate gland determines the main profiles of post-radiation damage: rectal and genitourinary radiation toxicity. The previous five years have been marked by a significant intensification of research work abroad aimed at clinical testing of a number of biopolymer compositions and products for use as spacers between irradiated structures and normal tissues. The experience has made it possible for the first time to consider the possibility of using spacers in radiotherapy treatment of prostate cancer in the modern recommendations of the European Association of Urology (2021). The analysis of the national literature shows a complete lack of publications on the possibilities of optimizing the radiation treatment of prostate cancer through the use of specers. The purpose of this work was the need to highlight this important and perspective clinical problem.

Characteristics Assessment of Online YouTube Videos on Radiotherapy for Lung Cancer

IntroductionThe internet has become a mainstay source of health information for cancer patients. Online patient education videos are common; however, there have been no studies examining the quality of publicly available videos on radiotherapy for lung cancer (one of the most common forms of cancer). To fill this knowledge gap, we aim to systematically map and objectively assess videos discussing radiotherapy for lung cancer on YouTube.MethodsThe terms “radiotherapy for lung cancer,” “radiation for lung cancer,” “radiation therapy for lung cancer,” and “radiation treatment for lung cancer” were searched on YouTube using a clear-cache browser. Results were sorted by relevance and the top 50 English-language results for each search were recorded. After removing duplicates, each video was assessed for length, Video Power Index (VPI, which is the product of a video’s average daily views and like and dislike ratio), source, content, comment moderation, and misinformation. Two raters were used to ensure consistency. Results were evaluated using descriptive and inferential statistics.ResultsA total of 88 unique videos resulted from the search. The median video length was 4 minutes and 5 seconds. The average VPI was 10.9 (95% CI: 1.5-20.4) and the median number of views was 954.5. All videos were published between July 8, 2009 and November 18, 2020. Of the videos, 44% were published within the past two years. A total of 61% of the videos were from the USA, 14% were from the UK, 6% from Australia, 5% each from Canada and India, and other countries make up the remaining 10%. Most of the videos were published by healthcare facilities (39%) and non-profit organizations (31%). Content-wise, 95% of videos contain information specific to lung cancer. A total of 46 videos (52%) were targeted toward patient education. Of which, 37 covered radiotherapy for lung cancer, 12 covered side effects for radiotherapy, and 11 covered both. The other 42 videos (48%) were designed for a professional audience. Stereotactic body radiation therapy (SBRT)/stereotactic ablative radiotherapy (SABR) was the most commonly described radiotherapy modality (42%), and the physician interview was the most common format, being used in 59% of videos. Out of the 38 videos with at least one comment, only two (5%) were moderated by the host channel. None of the videos featured misleading information.ConclusionsThis study comprehensively surveyed YouTube videos pertaining to radiotherapy for lung cancer to provide a high-level overview of the information that patients may find online. Although nearly half of the videos describe lung cancer radiotherapy for patients, only a small proportion comprehensively cover both radiotherapy and its side effects. The results of our study can help guide the development of patient education tools and encourage healthcare providers to recognize the limitations of online health information and proactively address patient questions regarding radiotherapy. Future research could examine videos on other lung cancer treatment options or radiotherapy for other cancers.

Patch-Based DCNN Method for CBCT Image Enhancement

Cone-beam computed tomography (CBCT) often has suboptimal image quality compared with standard fan-beam CT due to increased sensitivity to scattering and motion artifacts. In radiation treatment of cancers, due to the convenience in image acquisition as it is fully incorporated into the treatment station, CBCT plays a significant role in treatment plan re-evaluation and adaptation in adaptive radiation therapy but is limited by the image quality. In this paper, we propose a deep convolutional neural network (DCNN) based method for head and neck (HN) CBCT enhancement, where the network learns to transform the low-quality CBCT images to high-quality images.CT and CBCT image pairs from 50 HN cancer patients who received radiotherapy treatment were used for model training, validation and testing. An additional 22 raw CBCT images from another vendor were also used for testing. Pre-processing procedures include rigid registration, center-cropping, and Otsu's thresholding to segment the anatomical region. Data quality control was applied before training a 2D U-Net to reduce the adverse impact from the unmatched pairs. A patch-based strategy was employed during training, since the randomly extracted patches could reduce the receptive field and thus reduce the probability of overfitting based on the global anatomy. We explored the impact of patch size by varying it to be 64 × 64, 128 × 128, 192 × 192 and 256 × 256. After fixing to the optimal patch size, a Pix2Pix network combining L1 loss and conditional generative adversarial network (GAN) loss was also trained.It was found that the U-Net trained with a patch size of 128 × 128 reached the optimal performance and improved the mean absolute error (MAE) from 57.91 to 34.78 Hounsfield units (HU), peak signal-to-noise ratio (PSNR) from 30. 56 to 32.84 dB, and structural similarity (SSIM) from 0.7546 to 0.8455 compared with the original CBCT. With the addition of conditional GAN loss, the trained Pix2Pix network better kept the image details, especially on the external testing set.In this work, we developed a DCNN-based method to improve the CBCT image quality. This method has the advantages of high adaptability, vendor neutrality and low cost, since it operates purely in the image domain. Our data quality control pipeline automatically removed the unmatched CT and CBCT image pairs from the training set. The proposed DCNN-based method with the patch-based training strategy showed promising results for fast CBCT image enhancement.

Can EBRT Dose-Escalation Above 80 Gy Yield Comparable Survival Rates Relative to EBRT Plus Brachytherapy Boost in Men With Unfavorable Intermediate-Risk Prostate Cancer?

<h3>Purpose/Objective(s)</h3> Current recommendations regarding radiotherapy treatment for unfavorable intermediate-risk prostate cancer (UIR-PCa) include external beam radiotherapy (EBRT) ± brachytherapy boost (BT) ± androgen deprivation therapy (ADT). Dose-escalated EBRT ± ADT is associated with excellent long-term outcomes, but ERBT+BT ± ADT can achieve higher dose escalation beyond what can be achieved with EBRT alone. Prior studies have shown improved biochemical control and reduced distant metastasis with EBRT+BT vs. EBRT in men with intermediate-risk disease, but it is unclear if this translates into a survival benefit. <h3>Materials/Methods</h3> Men with UIR-PCa diagnosed between 2004 and 2015 and treated with EBRT ± ADT or EBRT+BT ± ADT were identified in the National Cancer Database (NCDB). EBRT was delivered with conventional fractionation (≥ 72 Gy in 1.8-2.0 Gy per fraction), while EBRT+BT was defined as patients receiving EBRT to a total dose of 40-50.4 Gy plus high-dose rate or low-dose rate brachytherapy. Patients with a Charlson-Deyo comorbidity index (CDCI) score > 1, who received systemic therapy other than ADT, or missing key information were excluded. Propensity-weighted multivariable analysis (MVA) using Cox regression modeling was used to compare overall survival (OS) hazard ratios. Covariables included age, race, ethnicity, year of diagnosis, CDCI score, insurance status, educational and socioeconomic metrics, treatment at an academic center, PSA at diagnosis, Gleason score, clinical T-stage, and receipt of ADT. <h3>Results</h3> The study cohort included 32,246 unfavorable intermediate-risk prostate cancer patients treated with: (<b>i</b>) EBRT (n = 13,265), (<b>ii</b>) EBRT+ADT (n = 13,123), (<b>iii</b>) EBRT+BT (n = 3,440), or (<b>iv</b>) EBRT+BT+ADT (n = 2,418). Cumulative doses of EBRT ± ADT are summarized in Table 1. The average time to follow-up was 62 months (standard deviation ± 39 months). Propensity-weighted MVA showed that EBRT+BT ± ADT was associated with improved OS relative to increasing doses of EBRT ± ADT. However, the OS benefit associated with EBRT+BT ± ADT diminished as the cumulative dose of radiation in the EBRT ± ADT cohort increased (Table 1). <h3>Conclusion</h3> The addition of brachytherapy to EBRT correlated with reduced mortality in men with UIR prostate cancer, including patients treated with EBRT ± ADT to ≥80 Gy. The relative OS benefit associated with EBRT+BT declined as the radiation dose increased in the EBRT ± ADT cohort.

Trigger-Based Adaptive Planning to Reduce Bowel Dose in Patients Receiving Radiotherapy for Anal Cancer

<h3>Purpose/Objective(s)</h3> Standard of care for locally advanced anal carcinoma is definitive chemoradiation with IMRT. Currently, target and organ-at-risk (OAR) volumes are created using a pre-treatment CT-simulation scan. However, during the course of radiotherapy, there is often change in the size and/or position of the tumor and surrounding normal structures. Therefore, we hypothesize that the implementation of an adaptive radiation therapy treatment protocol in anal cancer may reduce radiation dose to critical surrounding normal structures, such as the bowel, through the use of anatomy-adapted replanning. <h3>Materials/Methods</h3> Retrospective daily adaptive CTs were created for 4 patients (54 Gy, 30 fraction VMAT) in an oncology imaging informatics system using the Adaptive Calculation and Tracking for Offline Plan Review (ACTOR) toolkit. Each adaptive CT was created by deformable image registration (dir) of the planning CT to the daily CBCT. The structure sets from the planning CT were deformed onto each adaptive CT and ultimately corrected and revised by two qualified radiation oncologists. The adaptive CTs were transferred to a treatment planning system for recalculation. The original treatment plan was recalculated on each fraction adaptive CT to establish the real dose received during treatment. A two-sample t-test was used to compare the average real dose received dosimetric values to the values obtained on trigger-based adaptive planning. <h3>Results</h3> Using dose prescriptions for target volumes and normal tissue dose constraints as defined in RTOG 0529 (Kachnic et al 2013), normal bowel dose metrics, including bowel V45 < 20cc, were tracked as possible triggers for adaptation. Using bowel V45 > 20cc as trigger 1, there was a significant reduction in bowel V45 for each patient (table), with an average reduction in bowel V45 of 86.7% (<i>P</i> = 0.0001) across all patients. Adapting only the 5 fractions with the highest values for bowel V45 (trigger 2), we also found a significant reduction for each patient (table), with an average reduction of 20.8 % (<i>P</i> = 0.0011) across all patients. <h3>Conclusion</h3> Our study demonstrated that triggered adaptive re-planning using bowel V45 > 20cc could likely achieve reductions in normal tissue dose. Adaptive planning during radiation treatment of anal cancer may therefore be beneficial for reduction of treatment-related GI toxicity. These results can help inform a future randomized trial of adaptive therapy vs. standard planning.

Characteristics Assessment of Online YouTube Videos on Radiotherapy for Lung Cancer

The internet has become a mainstay source of health information for cancer patients. Online patient education videos are common, however, there has been no studies examining the quality of publicly available videos on radiotherapy for lung cancer (one of the most common forms of cancer). To fill this gap in knowledge, we aim to systematically map and objectively assess videos discussing radiotherapy for lung cancer on YouTube.The terms "radiotherapy for lung cancer," "radiation for lung cancer," "radiation therapy for lung cancer," and "radiation treatment for lung cancer" were searched on YouTube using a clear-cache browser. Results were sorted by "Relevance" and the top 50 English-language results for each search were recorded. After removing duplicates, each video was assessed for length, Video Power Index (VPI, which is the product of a video's average daily views and like: dislike ratio), source, content, comment moderation, and misinformation. Two raters were used to ensure consistency. Results were evaluated using descriptive and inferential statistics.88 unique videos resulted from the search. The median video length was 4 minutes and 5 seconds. The average VPI was 10.9 (95% CI: 1.5-20.4) and the median number of views was 954.5. All videos were published between July 8, 2009 and November 18, 2020. 44% were published within the past two years. 61% of the videos were from the USA, 14% were from the UK, 6% from Australia, 5% each from Canada and India, and other countries make up the remaining 8%. Most of the videos were published by healthcare facilities (39%) and non-profit organizations (31%). Content-wise, 95% of videos contain information specific for lung cancer. 46 videos (52%) were targeted towards patient education. Of which, 37 covered radiotherapies for lung cancer, 12 covered side effects for radiotherapy, and 11 covered both. The other 42 videos (48%) were designed for a professional audience. SBRT/SABR was the most commonly described radiotherapy modality (42%), and the physician interview was the most common format, being used in 59% of videos. Out of the 38 videos with at least one comment, only 2 (5%) were moderated by the host channel. None of the videos featured misleading information.This study comprehensively surveyed YouTube videos pertaining to radiotherapy for lung cancer to provide a high-level overview of the information that patients may find online. Although nearly half of the videos describe lung cancer radiotherapy for patients, only a small proportion comprehensively cover both radiotherapy and its side effects. The results of our study can help guide development of patient education tools and encourage healthcare providers to recognize limitations of online health information and proactively address patient questions regarding radiotherapy. Future research could examine videos on other lung cancer treatment options or radiotherapy for other cancers.

Association of Gut Microbiome Characteristics With the Late Gastrointestinal Toxicities After Pelvic Receiving Radiation Treatment for Cervical, Vaginal, and Anal Cancers

Radiation therapy is curative for treating cervical, vaginal, and anal cancers, but can lead to gut toxicities that reduce quality of life in recovering patients. Previously, higher gut microbiome diversity was shown to be positively correlated with less severe acute gastrointestinal (GI) toxicities per patient-reported assessments of bowel function. The goal of this study was to explore effects of gut microbiome diversity and composition on late GI toxicities. We hypothesized that the occurrence of late GI toxicities in patients that receive abdominal radiation therapy correlates with gut microbiome diversity.We collected and analyzed rectal swabs from 66 patients with cervical, anal, and vaginal cancer receiving standard of care treatment. Samples from baseline and week 5 of treatment were sequenced using 16Sv4 ribosomal RNA (rRNA) gene sequencing. We also retrospectively evaluated the late (occurring after 3 months) radiation induced GI toxicities of patients who had completed their treatment 2 years prior using the RTOG/EORTC Late Radiation Morbidity Scoring Schema and the Common Terminology Criteria for Adverse Events (CTCAE) v.5. The gut microbial diversity of the patients was then characterized by indexes of richness, evenness and diversity. 59 patients were included in the analysis; exclusion criteria were lack of either follow-up or microbiome data and receiving additional radiation therapy or chemotherapy. Independent students t-tests were used to compare the alpha diversity metrics between patients who experienced late toxicities and those who did not. Beta diversity was evaluated using linear discriminant analysis effect size (LEfSe) to identify bacteria taxa that were differentially enriched in groups of patients with no toxicity against those with toxicity, and independent t-tests were used to compare the relative abundances of these taxa between patients with and without late toxicities.37.3% of patients per RTOG/EORTC criteria and 42.4% per CTCAE criteria experienced late GI toxicities (RTOG > = 1, CTCAE > = 1). Overall, neither the alpha diversity at baseline nor at week 5 was significantly different in patients who experienced late toxicities compared with those who didn't. Of the 22 taxa identified in the LEFse analysis, Sutterella species were higher at baseline in patients who did not experience late GI toxicities (0.21% vs. 0.72%, respectively, P = 0.01 for RTOG/EORTC criteria; 0.19% vs. 0.79%, respectively, P = 0.004 per CTCAE criteria).The presence of Sutterella was significantly associated with late toxicity, consistent with prior observations of acute toxicity. Overall, is no strong association between gut microbiome diversity and the presence of late GI toxicities in patients who have received radiation therapy for cervical, vaginal, and anal cancers. The observation has implications in the ongoing search for gut microbiome-targeted treatments for mitigating side effects of radiation.E.J. Lynn: None. M.B. El Alam: None. T. Karpinets: None. D. Lin: None. R. Kouzy: None. K. Court: None. X. Wu: None. M.P. Mezzari: None. N. Ajami: None. T. Solley: None. L.L. Lin: Employee; VA Hospital. Research Grant; AstraZeneca. Travel Expenses; AstraZeneca. L. Ramondetta: None. A. Jhingran: American Board of Radiology. P.J. Eifel: Travel Expenses; National Cancer Center Network. Stock; Apple Computer. K. Schmeler: None. B.D. Minsky: None. E.J. Koay: Research Grant; PANCAN-AACR, MD Anderson Cancer Center, Philips, National Institutes of Health, General Electric, Elekta, Stand Up 2 Cancer, Project Purple. Royalty; Taylor and Francis LLC. Patent/License Fees/Copyright; Pending Patent. I help coordinate scientific and advocacy activities for this Foundation, focused on radiation oncology. P. Das: Honoraria; MD Anderson Cancer Center Madrid, National Cancer Institute/Leidos, ASTRO. Consultant; Adlai Nortye. C.M. Taniguchi: Research Grant; NIH, Reaumond Foundation, Mark Foundation. Consultant; Phebra Pty, Ltd, Xerient Pharmaceuticals. Advise on various radiation products; Accuray. A.H. Klopp: Research Grant; MD Anderson Cancer Center SPORE Grant. L. Colbert: None.

Speech and Swallowing Outcomes Following Surgical Resection with Immediate Free Tissue Transfer Reconstruction for Advanced Osteoradionecrosis of the Mandible Following Radiation Treatment for Head and Neck Cancer

Despite recent advances in the radiation techniques used for the treatment of head and neck cancer (HNC) including intensity-modulated radiotherapy (IMRT), mandibular osteoradionecrosis (ORN) remains a significant complication. Advanced stage ORN is managed surgically with resection and immediate free tissue transfer reconstruction. An evaluation of the functional speech and swallowing outcomes was undertaken for patients undergoing surgical management of advanced ORN. We retrospectively reviewed consecutive patients, at a single, tertiary cancer centre, who underwent surgical resection for advanced Notani grade III ORN. Outcomes investigated included use and duration of tracheostomy and swallowing and speech status using Performance Status Scale for Head and Neck Cancer Normalcy of Diet (PSS-NOD) and Understandability of Speech (PSS-Speech) at baseline and 3 months following surgery. Ten patients underwent surgical resection with free tissue transfer reconstruction between January 2014 and December 2019. Two patients required supplemental nutrition via a gastrostomy at three months post surgery. As per the PSS-NOD data half of the patients’ (n = 5) diet remained stable (n = 2) or improved (n = 3) and half of the participants experienced a decline in diet (n = 5). The majority of patients had no speech difficulties at baseline (n = 8). The majority of patients’ speech remained stable (n = 8) with two patients experiencing a deterioration in speech clarity following surgery. Well-designed studies with robust, sensitive multidimensional dysphagia and communication assessments are required to fully understand the impact of surgical management of advanced ORN using resection with free tissue transfer reconstruction.

The Effect of Measured Radiotherapy Dose on Intrathecal Drug Delivery System Function

Radiation therapy (RT) and intrathecal drug delivery systems (IDDS) are often used concurrently to optimize pain management in patients with cancer. Concern remains among clinicians regarding the potential for IDDS malfunction in the setting of RT. Here we assessed the frequency of IDDS malfunction in a large cohort of patients treated with RT. Cancer patients with IDDS and subsequent RT at our institution from 2011 to 2019 were eligible for this study. Patients were excluded in the rare event that their IDDS was managed by an outside clinic and follow-up documentation was unavailable. Eighty-eight patients aged 22-88 years old (43% female, 57% male) representing 106 separate courses of RT were retrospectively identified. Patients received varying levels of radiation for treatment of cancer and cumulative dose to the IDDS was calculated. IDDS interrogation was subsequently performed by a pain specialist. Malfunction was recorded as deviation from the expected drug volume and/or device errors reported upon interrogation as defined by the manufacturer. Total measured RT dose to the IDDS ranged from 0 to 18.0Gy (median=0.2Gy) with median dose of 0.04 Gy/fraction (range, 0-3.2 Gy/fraction). Ten pumps received a total dose >2Gy and three received ≥5Gy. Eighty-two percentage of patients had follow-up with a pain specialist for IDDS interrogation and all patients underwent follow-up with a healthcare provider following RT. There were zero incidences of IDDS malfunction related to RT. No patient had clinical evidence of radiation related pump malfunction at subsequent encounters. We found no evidence that RT in patients with IDDS led to device failure or dysfunction. While radiation oncologists and pain specialists should coordinate patient care, it does not appear that RT dose impacts the function of the IDDS to warrant significant clinical concern.

Development of Patient Specific Conformal 3D-Printed Devices for Dose Verification in Radiotherapy

In radiation therapy, a bolus is used to improve dose distribution in superficial tumors; however, commercial boluses lack conformity to patient surface leading to the formation of an air gap between the bolus and patient surface and suboptimal tumor control. The aim of this study was to explore 3D-printing technology for the development of patient-specific conformal 3D-printed devices, which can be used for the radiation treatment of superficial head and neck cancer (HNC). Two 3D boluses (0.5 and 1.0 cm thick) for surface dose build-up and patient-specific 3D phantom were printed based on reconstruction of computed tomography (CT) images of a patient with HNC. The 3D-printed patient-specific phantom indicated good tissue equivalency (HU = −32) and geometric accuracy (DSC = 0.957). Both boluses indicated high conformity to the irregular skin surface with minimal air gaps (0.4–2.1 mm for 0.5 cm bolus and 0.6–2.2 mm for 1.0 cm bolus). The performed dose assessment showed that boluses of both thicknesses have comparable effectiveness, increasing the dose that covers 99% of the target volume by 52% and 26% for single field and intensity modulated fields, respectively, when compared with no bolus case. The performed investigation showed the potential of 3D printing in development of cost effective, patient specific and patient friendly conformal devices for dose verification in radiotherapy.

The impact of dose calculation algorithm for SBRT lung cancer radiotherapy treatment

Introduction: The study aimed to provide the dose accuracy effects between Anisotropic Analytical algorithm (AAA) and the deterministic solver Acuros XB (AXB) that are available on Eclipse TPS (Varian Medical Systems, Palo Alto, CA) treatment planning system (TPS). The different is due to the electron transport difference in case of small fieldsMaterial and methods: For the study non-small cell lung cancer (NSCLC) patient CT scans are used to do retrospective SBRT plans via AAA and recalculated by AXB dose calculation algorithms using Eclipse treatment planning system. The main dosimetric comparison parameters are: Conformity index (CI), Homogeneity Index (HI), Gradient Index (GI), Target mean dose and calculation time. Results: Based on the results, the CI is (1.45±0.55) to (1.85±0.7). The HI are (0.15±0.07) and (0.13±0.08), the Gradient index GI for AAA were (4.8±2.6) and for AXB reaches to (7.4±3.8) and the maximum dose for PTV are differed about 2.3% to 4.5%, mean dose and the calculation time significant similar for AAA and AXB respectively.Conclusion: As the findings using the deterministic solver AXB in calculation for case of low density like lung cases is more accurate than AAA calculation Algorithm in SBRT treatment

Breast cancer suppression by curcumin-naringenin-magnetic-nano-particles: In vitro and in vivo studies.

The limitations of surgery, radiotherapy, and chemotherapy in cancer treatment and the increase in the application of nanomaterials in the field of biomedicine have promoted the use of nanomaterials in combination with radiotherapy for cancer treatment. To improve the efficiency of cancer treatment, curcumin-naringenin loaded dextran-coated magnetic nanoparticles (CUR-NAR-D-MNPs) were used as chemotherapy and in combination with radiotherapy to verify their effectiveness in treating tumors. CUR-NAR-D-MNPs were prepared and studied by several characterization methods. Median inhibitory concentration (IC50) and cellular toxicity were evaluated by 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) assay. The cell death and radiosensitization were studied by acridine orange/ethidium bromide dual staining of MCF-7 human breast cancer cells. CUR-NAR-D-MNPs induce apoptosis and inhibited cell proliferation through reactive oxygen species (ROS) generation. CUR-NAR-D-MNPs used alone had a certain therapeutic effect on tumors. CUR-NAR-D-MNPs plus radiotherapy significantly reduced the tumor volume and led to cell cycle arrest and induction of apoptosis through modulation of P53high, P21high, TNF-αlow, CD44low, and ROShigh signalingCONCLUSIONS:CUR-NAR-D-MNPs are effective in the treatment of tumors when combined with radiotherapy, and show radiosensitization effects against cancer proliferation in vitro and in vivo.

FDG-PET/CT and MR imaging for target volume delineation in rectal cancer radiotherapy treatment planning: a systematic review

AbstractAim:The aim of this systematic review was to synthesise and summarise evidence surrounding the clinical use of fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography (FDG-PET/CT) and magnetic resonance imaging (MRI) for target volume delineation (TVD) in rectal cancer radiotherapy planning.Methods:PubMed, EMBASE, Cochrane library, CINAHL, Web of Science and Scopus databases and other sources were systematically queried using keywords and relevant synonyms. Eligible full-text studies were assessed for methodological quality using the QUADAS-2 tool.Results:Eight of the 1448 studies identified met the inclusion criteria. Findings showed that MRI significantly delineate larger tumour volumes (TVs) than FDG-PET/CT while diffusion-weighted magnetic resonance imaging (DW-MRI) defined smaller gross tumour volumes (GTVs) compared to T2 weighted-Magnetic Resonance Image. CT-based GTVs were found to be larger compared to FDG-PET/CT. FDG-PET/CT also identified new lesions in 15–17% patients and TVs extending outside the routinely used clinical standard CT TV in 29–83% patients. Between observers, delineated volumes were similar and consistent between MRI sequences, whereas interobserver agreement was significantly improved with FDG-PET/CT than CT.Conclusion:FDG-PET/CT and DW-MRI appear to delineate smaller rectal TVs and show improved interobserver variability. Overall, this study provides valuable insights into the amount of attention in the research literature that has been paid to imaging for TVD in rectal cancer.