Radiotherapy In Treatment Of Cancer Research Articles

Current Evidence on Molecular Mechanisms of Andrographolide in Cancer.

Cancer, a diverse group of diseases characterized by abnormal cell growth and the potential to spread throughout the body, accounts for approximately 10 million deaths globally each year. Current cancer therapies, including chemotherapy, radiation, and various pharmacological treatments, present several challenges and potential side effects. It is important to differentiate these conventional methods, which often involve synthetic drugs, from adjuvant therapies that might be used in conjunction. As a result, there is an increasing interest in alternative therapies, particularly in agents derived from natural sources for cancer treatment. Secondary metabolites have shown promise in promoting the development of new clinical drugs with various anti-cancer mechanisms. This review focuses on the anti-cancer potential of the novel metabolite Andrographolide, extracted mainly from Andrographis paniculata. The chemopreventive properties and the ability to inhibit various signaling pathways across different types of cancers without side effects posit Andrographolide as a promising natural antitumour agent. The review identified that Andrographolide inhibits multiple signaling pathways, contributing to its anti-proliferative, anti-metastatic, and apoptotic effects in various cancers. The compound's natural origin and lack of adverse side effects make it particularly attractive as a therapeutic agent. However, further detailed studies are needed to fully understand its specific mechanisms and potential clinical applications. Andrographolide presents a compelling option as a natural anticancer agent with the potential to overcome some limitations of traditional cancer treatments. Its broad spectrum of anti-cancer activities and absence of side effects highlight its therapeutic potential. The review highlights that continued research and clinical studies are important for confirming the effectiveness and safety of Andrographolide in human use, alongside optimizing dosage and delivery techniques.

The Evolving Role of Artificial Intelligence in Radiotherapy Treatment Planning—A Literature Review

This paper examines the integration of artificial intelligence (AI) in radiotherapy for cancer treatment. The importance of radiotherapy in cancer management and its time-intensive planning process make AI adoption appealing especially with the escalating demand for radiotherapy.This review highlights the efficacy of AI across medical domains, where it surpasses human capabilities in areas such as cardiology and dermatology. Focusing on radiotherapy, the paper details AI's applications in target segmentation, dose optimization, and outcome prediction. It discusses adaptive radiotherapy's benefits and AI's potential to enhance patient outcomes with much improved treatment accuracy. The paper explores ethical concerns, including data privacy and bias, stressing the need for robust guidelines. Educating healthcare professionals and patients about AI's role is crucial as it acknowledges potential job-role changes and concerns about patients' trust in the use of AI.Overall, the integration of AI in radiotherapy holds transformative potential in streamlining processes, improving outcomes, and reducing costs. AI's potential to reduce healthcare costs underscores its significance with impactful change globally. However, successful implementation hinges on addressing ethical and logistical challenges and fostering collaboration among healthcare professionals and patient population data sets for its optimal utilization. Rigorous education, collaborative efforts, and global data sharing will be the compass guiding its' success in radiotherapy and healthcare.

Individual and neighborhood-level factors associated with disruptions in patients with gynecologic cancers undergoing radiation treatment.

e13713 Background: Disparities in cancer health outcomes are driven in part by social determinants of health (SDOH). Health-related social needs (HSRN) are downstream modifiable manifestations of SDOH. It is critical to identify patients with HRSN who may benefit from early intervention to improve health outcomes. Methods: We identified all patients who received radiation treatment (RT) for gynecologic cancer at an urban, academic center from January 2021-August 2023 and completed HRSN screening. HRSN screening queries patients on food, housing, transportation, and financial insecurity as well as help reading hospital materials. We extracted demographic and clinical data, self-reported HRSNs, and separately screened each chart for additional evidence of transportation insecurity. We extracted area deprivation index (ADI), a measure of neighborhood level socioeconomic disadvantage, based on home address. Any RT disruption was the primary outcome. We compared patients with and without any RT disruption using Fisher’s exact tests. Univariate Poisson regression was used to examine the magnitudes of association between individual and neighborhood level factors and RT disruption. Results: A total of 127 patients met inclusion criteria. Median age was 62 (interquartile range 25%-75%: 53-71). Most (54%, n=69) patients were White, 32% were Black (n=41), and 14% were another race (n=17). Sixteen percent (n=20) reported at least one HRSN. Six percent of patients (n=8) resided in neighborhoods in the 81st-100th percentile ADI. A total of 26% (n=33) of patients had any RT disruption, and these patients differed on individual and neighborhood factors (Table). Patients with public insurance were 2.4 times as likely to have RT disruption compared to those with private insurance (95% confidence interval [CI]: 1.4-4.2). Self-reporting at least one HRSN was associated with a 2.3 times higher risk of RT disruption (95% CI: 1.31-4.11). Chart-derived evidence of transportation insecurity was associated with a 2.6 times higher risk (95%CI: 1.5-5.6) of RT disruption. Residing in a neighborhood with an ADI above the 80%ile was associated with a 3.3 times higher risk (95% CI: 2.0-5.5) of disruption. Conclusions: A variety of measures of SDOH both at the individual and neighborhood-level were associated with RT disruptions. While we did not have the power to perform multivariate analyses, our results suggest the ADI – which can be readily obtained from a patient’s home address – could help identify those patients most at risk of disruption to care. [Table: see text]

Advances in highly targeted radiation treatment for cancer have ignited interest in a once obscure field.

Advances in highly targeted radiation treatment for cancer have ignited interest in a once obscure field.

Transperineal versus transrectal prostate fiducial insertion in radiation treatment of prostate cancer: a systematic review and meta-analysis.

To provide more accurate and definitive conclusions regarding the clinical and technical complications associated with the transperineal (TP) and transrectal (TR) approaches, a comprehensive review of observational studies and randomized controlled trials was conducted. This systematic review covered all eligible studies to facilitate a thorough comparison of complications linked to the two fiducial marker insertion methods, TP and TR. A comprehensive search of the literature was conducted, encompassing databases such as PubMed, Embase, and the Cochrane Library, up to July 7, 2023. The relative risk and 95% confidence interval were utilized to evaluate the diagnosis and complication rates. The final selection for the methodological quality analysis included 13 observational studies that utilized TP and TR gold fiducial insertion approaches. The meta-analysis revealed significantly lower risks of urinary tract infections (UTI) and rectal bleeding with the TP approach. The use of both TP and TR techniques for placing gold seed fiducial markers has proven to be an effective, safe, and well-tolerated method for image-guided radiation therapy in prostate cancer patients. A significant benefit of the TP technique is its ability to avoid rectal puncture, thereby reducing the risk of UTIs. Although the incidence of UTIs and rectal bleeding associated with the TR method is relatively low, these complications can disrupt patient wellbeing and potentially cause delays in treatment.

Insights into pelvic insufficiency fracture following pelvic radiotherapy for cervical cancer: a comparative review

BackgroundRadiotherapy (RT)-induced pelvic insufficiency fractures (PIF) are prevalent in patients with cervical cancer. Inconclusive studies on PIF after cervical irradiation create uncertainty. This review examined PIF after RT in cervical patients, including its pathobiology, likely locations of fractures, incidence, clinical symptoms, and predisposing factors. We further discussed study limitations and therapeutic possibilities of PIF.MethodsThe following online resources were searched for relevant articles: Google Scholar and PubMed. The keywords ‘pelvic insufficiency fractures’, ‘cervical carcinoma’ and ‘cervical cancer’, as well as ‘chemoradiotherapy’, ‘chemoradiation’, and ‘radiotherapy’, were some of the terms that were used during the search.ResultsPatients with PIF report pelvic pain after radiation treatment for cervical cancer; the incidence of PIF ranges from 1.7 to 45.2%. Evidence also supports that among all patients treated with pelvic radiation, those who experienced pelvic insufficiency fractures invariably had at least one sacral fracture, making it the most frequently fractured bone in the body. Menopausal status, weight, BMI, age, and treatments and diagnosis modalities can influence PIF during radiotherapy.ConclusionsIn conclusion, our comparative review of the literature highlights significant heterogeneity in various aspects of PIF following radiation for patients with cervical cancer. This diversity encompasses prevalence rates, associated risk factors, symptoms, severity, diagnosis methods, preventive interventions, and follow-up periods. Such diversity underscores the complexity of PIF in this population and emphasizes the critical need for further research to elucidate optimal management strategies and improve patient outcomes.

Unraveling the Complexity of DNA Radiation Damage Using DNA Nanotechnology.

Radiation cancer therapies use different ionizing radiation qualities that damage DNA molecules in tumor cells by a yet not completely understood plethora of mechanisms and processes. While the direct action of the radiation is significant, the byproducts of the water radiolysis, mainly secondary low-energy electrons (LEEs, <20 eV) and reactive oxygen species (ROS), can also efficiently cause DNA damage, in terms of DNA strand breakage or DNA interstrand cross-linking. As a result, these types of DNA damage evolve into mutations hindering DNA replication, leading to cancer cell death. Concomitant chemo-radiotherapy explores the addition of radiosensitizing therapeutics commonly targeting DNA, such as platinum derivatives and halogenated nucleosides, to enhance the harmful effects of ionizing radiation on the DNA molecule. Further complicating the landscape of DNA damage are secondary structures such as G-quadruplexes occurring in telomeric DNA. These structures protect DNA from radiation damage, rendering them as promising targets for new and more selective cancer radiation treatments, rather than targeting linear DNA. However, despite extensive research, there is no single paradigm approach to understanding the mysterious way in which ionizing radiation causes DNA damage. This is due to the multidisciplinary nature of the field of research, which deals with multiple levels of biological organization, from the molecular building blocks of life toward cells and organisms, as well as with complex multiscale radiation-induced effects. Also, intrinsic DNA features, such as DNA topology and specific oligonucleotide sequences, strongly influence its response to damage from ionizing radiation. In this Account, we present our studies focused on the absolute quantification of photon- and low-energy electron-induced DNA damage in strategically selected target DNA sequences. Our methodology involves using DNA origami nanostructures, specifically the Rothemund triangle, as a platform to expose DNA sequences to either low-energy electrons or vacuum-ultraviolet (VUV, <15 eV) photons and subsequent atomic force microscopy (AFM) analysis. Through this approach, the effects of the DNA sequence, incorporation of halogenated radiosensitizers, DNA topology, and the radiation quality on radiation-induced DNA strand breakage have been systematically assessed and correlated with fundamental photon- and electron-driven mechanisms underlying DNA radiation damage. At lower energies, these mechanisms include dissociative electron attachment (DEA), where electrons attach to DNA molecules causing strand breaks, and dissociative photoexcitation of DNA. Additionally, further dissociative processes such as photoionization and electron impact contribute to the complex cascade of DNA damage events induced by ionizing radiation. We expect that emerging DNA origami-based approaches will lead to a paradigm shift in research fields associated with DNA damage and suggest future directions, which can foster the development of technological applications in nanomedicine, e.g., optimized cancer treatments or the molecular design of optimized radiosensitizing therapeutics.

Lumbar and Thoracic Vertebrae Segmentation in CT Scans Using a 3D Multi-Object Localization and Segmentation CNN.

Radiation treatment of cancers like prostate or cervix cancer requires considering nearby bone structures like vertebrae. In this work, we present and validate a novel automated method for the 3D segmentation of individual lumbar and thoracic vertebra in computed tomography (CT) scans. It is based on a single, low-complexity convolutional neural network (CNN) architecture which works well even if little application-specific training data are available. It is based on volume patch-based processing, enabling the handling of arbitrary scan sizes. For each patch, it performs segmentation and an estimation of up to three vertebrae center locations in one step, which enables utilizing an advanced post-processing scheme to achieve high segmentation accuracy, as required for clinical use. Overall, 1763 vertebrae were used for the performance assessment. On 26 CT scans acquired for standard radiation treatment planning, a Dice coefficient of 0.921 ± 0.047 (mean ± standard deviation) and a signed distance error of 0.271 ± 0.748 mm was achieved. On the large-sized publicly available VerSe2020 data set with 129 CT scans depicting lumbar and thoracic vertebrae, the overall Dice coefficient was 0.940 ± 0.065 and the signed distance error was 0.109 ± 0.301 mm. A comparison to other methods that have been validated on VerSe data showed that our approach achieved a better overall segmentation performance.

Nutritional support in the complex of medical rehabilitation at the stage of adjuvant radiation therapy of breast cancer

BACKGROUND: Currently it is known that there exists the need for complex medical rehabilitation at the stage of adjuvant radiation treatment of breast cancer. However, data on the combined use of nutritional support and physical factors at this stage of oncological treatment are not available. AIM: Evaluation of the effectiveness of specialized therapeutic and preventive nutrition in patients with malignant breast diseases and a history of polychemotherapy at the stage of adjuvant radiation therapy in complex medical rehabilitation using low-temperature plasma and general magnetic therapy. MATERIALS AND METHODS: A prospective simple randomized study was conducted, which involved 60 patients at the stage of adjuvant radiation therapy for breast cancer. The main group (n=30) received a course of medical rehabilitation with the inclusion of nutritional support using specialized therapeutic and preventive nutrition LEOVIT ONCO®, as well as exposure to low-temperature plasma and general magnetotherapy. In the comparison group (n=30), the rehabilitation course included general magnetic therapy without therapeutic and preventive nutrition. All patients underwent individual physiotherapy exercises, and sessions with a medical psychologist. The results obtained were recorded using clinical and functional, laboratory, instrumental studies. RESULTS: It has been established that the use of specialized dietary products LEOVIT ONCO and physical factors is an effective method of rehabilitation. The use of nutritional support demonstrates the maintenance of the patient’s protein status, reduces intoxication, and reduces the negative impact of oxidative stress factors in the body at the stage of adjuvant radiation treatment. The inclusion of low-temperature plasma and general magnetic therapy in the rehabilitation program has a beneficial effect on hemomicrocirculation in the area of ionizing radiation exposure. CONCLUSION: The use of nutritional support and physical factors, as a component of complex medical rehabilitation, helps to maintain the optimal nutritional status of the patient, reduces the manifestations of skin radiation reactions, improves the psycho-emotional state of patients and the quality of life of patient.

Abstract PO4-16-08: Prognostic factors for tumor recurrence after breast-conserving and radiotherapy treatment for early invasive breast cancer: ten years of results in a referral center in Mexico City

Abstract Background: Breast cancer is the most common malignancy in the world, reporting more than 2 million new cases in 2020. In early stages, patients undergo primary surgery. Breast-conserving surgery (BCS) has generally been accepted as a treatment for invasive breast cancer, findings at 20 years still show that lumpectomy and breast irradiation, as compared with mastectomy, have no significant difference in overall survival among the treatment groups. Approximately 10-15% of patients will develop local or systemic recurrence in 5 to 10 years. Factors such as young age (&amp;lt; 45 years), close/positive margins, no breast radiation, are associated with ipsilateral breast tumor recurrence. High grade has been related to distant metastasis. The mortality trend is upward due to a higher incidence of the disease and earlier detection. Methods: This is an observational and retrospective cohort study, which included patients with early breast cancer, who were treated with conserving surgery and received radiotherapy, at the Breast Oncology Service at the UMAE Gineco 4 "Luis Castelazo Ayala" during the period from January 2012 to December 2022. The aim of our study was to describe the prognostic factors associated with disease-free survival (DFS) and overall survival (OS) in patients with localized breast cancer treated with BCS. DFS was defined as time from surgery to recurrence event (local recurrence, distant recurrence, contralateral breast cancer, second primary cancer, or death from any cause) whichever occurred first. For statistical analysis, Kaplan Meier and Log-rank methods were used for survival analysis. Cox proportional hazard model was used for multivariate analysis. Results: We included 399 patients, the median follow-up was 88 months (95%CI 86-91). Median age was 59 years. The most common pathological stage was IA in 44.9%, the predominant immunophenotype was luminal A in 56.1% of patients, follow by luminal B in 19.3% and 13% were triple negative. Management of axilla with sentinel node biopsy occurred in 50.1% and 49.9% underwent to lymph node dissection. Regarding surgery outcomes 40.4% of the patients required widening of the margins, 5% of the patients remained with close surgical margins ≤2 mm, 7.5% had complications associated with the surgery, and none related death ocurred. All patients received adjuvant radiotherapy, the median time to initiation was 32 weeks (range 3-70) and 65.4% received adjuvant chemotherapy. Recurrence events occurred in 15.5% of patients, local 2.8%, systemic 8.8%, contralateral breast cancer 1.7%, and second primary 2.2%. Estimated disease-free survival at 5 and 10 years were 86.6% and 74.2%, respectively. In the multivariate analysis independent prognostic factors for DFS were: lobular histology HR 2.95 (95%IC 1.5-5.7), tumor size ≥ 2cm HR 1.95 (95%IC 1.1-3.6), close surgical margins HR 2.62 (95%IC 1-6.6), and ER low expression (1-10%) HR 4.39 (95%CI: 1.6-12.4). Estimated OS at 5 and 10 years for patients who experienced recurrence were 78.4% and 47.4% and for patients without recurrence were 96.8% and 93.5%, respectively (adjusted HR: 10.4, 95%CI: 5.2-20.6). Conclusion: These results suggest that patients with early breast cancer treated with conserving surgery and radiotherapy with risk factors such as lobular carcinoma, tumor size ≥2cm, close margins, and low expression of estrogen receptors have a high risk of recurrence and significantly decreased overall survival at 5 and 10 years. Citation Format: Nayeli Ortega-Avila, Yuly A. Remolina-Bonilla, Janett Caballero-Jasso. Prognostic factors for tumor recurrence after breast-conserving and radiotherapy treatment for early invasive breast cancer: ten years of results in a referral center in Mexico City [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO4-16-08.

Simulation of Boron Dose and Irradiation Time in Lung Cancer Treatment with Boron Neutron Capture Therapy (BNCT) Using MCNP-6

&lt;p&gt;Boron Neutron Capture Therapy (BNCT) is a cancer radiation treatment. This approach employs a boron carrier agent in the form of a chemical that is injected into the body and then travels to the cancer cells. In a lung cancer case study, BNCT treatment simulation was carried out using Monte Carlo N Particle (MCNP) software version 6.2. The goal of this study was to determine the most effective boron concentration and irradiation duration in lung cancer therapy utilizing the BNCT method. The geometry based on a phantom model created by Oak Ridge National Laboratory (ORNL). The simulated cancer geometry, which is placed in the right lung's middle lobe. The skin, ribs, and right lung are among the organs at risk. The skin, ribs, and right lung are among the organs at risk. The neutron source for the simulation is the collimator output from the Kartini Nuclear Reactor's thermal column. In this simulation, the variations in boron concentrations were 40 g/g, 45 g/g, 50 g/g, 55 g/g, and 60 g/g of cancer tissue at 5 g/g intervals. The researchers discovered a link between boron injection concentration and irradiation time, with higher boron injection concentrations resulting in shorter irradiation times. The volume of boron injected determines the effective dose absorbed by healthy tissue surrounding cancer cells. The effective boron concentration for lung cancer therapy is 60 g/g, with deterministic cell killing in the rib marrow and right lung. When utilizing a boron concentration of 60 g/g, the irradiation time is 20.4 minutes. Boron concentrations of 60 g/g are projected to create an effective irradiation time for BNCT-based lung cancer therapy based on the ALARA principle due to their shorter duration when compared to other concentration variations.&lt;/p&gt;

Metastasis in the periocular region

Orbital and periocular metastatic tumors used to be considered very rare; however, with the constant updating of drugs and detection methods for cancer treatment, new chemotherapies and radiation treatments are being used. The life expectancy of cancer patients has become longer and periocular metastases are becoming easier to detect. Our knowledge of this rare disease of metastases also needs to be updated. This article reviews the incidence, symptomatic presentation, clinical features, diagnostic approaches and current treatment of metastatic tumors of the orbit and ocular adnexa in these patients.

Increasing the efficiency of cone-beam CT based delta-radiomics using automated contours to predict radiotherapy-related toxicities in prostate cancer

Extracting longitudinal image quantitative data, known as delta-radiomics, has the potential to capture changes in a patient’s anatomy throughout the course of radiation treatment for prostate cancer. Some of the major challenges of delta-radiomics studies are contouring the structures for individual fractions and accruing patients’ data in an efficient manner. The manual contouring process is often time consuming and would limit the efficiency of accruing larger sample sizes for future studies. The problem is amplified because the contours are often made by highly trained radiation oncologists with limited time to dedicate to research studies of this nature. This work compares the use of automated prostate contours generated using a deformable image-based algorithm to make predictive models of genitourinary and changes in total international prostate symptom score in comparison to manually contours for a cohort of fifty patients. Area under the curve of manual and automated models were compared using the Delong test. This study demonstrated that the delta-radiomics models were similar for both automated and manual delta-radiomics models.

Breast-Conserving Therapy and Irradiation in Women with Prior Breast Augmentation

Introduction: The incidence of breast-augmented women developing breast cancer is increasing and there is some disagreement regarding the optimal cancer treatment, in the setting of prior breast augmentation. The purpose of this study was to describe the outcome of Breast-conserving surgery and Radiation Treatment (BCT) for breast cancer, with preservation of the breast implants in breast-augmented women. Methods: Medical records of 30 women with prior breast augmentation, undergoing BCT at our institution between 2018 and 2021, were retrospectively reviewed. Data regarding complications, capsular contracture rates, oncological and overall cosmetic outcomes following treatment were registered. Results: Median follow-up time was 29 months with an overall complication rate of 30%. Surgeryrequiring complications (capsular contracture) were observed in 10% of the patients, one case resulting in implant removal and two cases resulting in implant exchange, whereas 20% had complications not requiring reoperation. Two patients (7%) had positive margins and underwent re-excision. No patients experienced cancer recurrence. Fifty percent of those with relevant information (n=3/6) developed or had worsening of capsular contracture, and 63% (n=7/11) were evaluated as having an excellent to good overall cosmetic appearance upon follow-up.

Abstract LB015: Differential expression of deubiquitinating enzymes and its related DNA damage response genes in neuroblastoma heterogeneity

Abstract SK-N-AS and SK-N-DZ are two cell lines of pediatric solid tumors neuroblastomas well characterized to evaluate heterogeneity between different neuroblastomas and are presumed as models for differences between different neuroblastoma. Using this model system, we recently evaluated if radiation could improve efficacy of radiation therapy and to follow these studies later with animal models to determine decrease of tumor burden. Differences between the N-type and S-type neuroblastoma cell lines SK-N-DZ and SK-N-AS, respectively were observed to be high and their responses to radiation stress were equally heterogeneous. Ubiquitin signaling plays a key role during the DNA damage response in protein recruitment and protein interactions. Deubiquitinating enzymes (DUBs) deconjugate ubiquitin from ubiquitylated substrate proteins to control their activity and stability and are shown to regulate various biological processes. DUBs may play a role in regulating the radiosensitivity of cancer cells by modulating DNA damage response and repair pathways. Determination of specific DUBs that are involved in regulating radiosensitivity in cancer cells will provide opportunity for drug targeting and visa-vis enhance the efficacy of radiation therapy in neuroblastoma cancer treatment. Here, using bioinformatic tools, the differentially regulated DUBs were identified. The relationship between DEGs-DUBs with the genes involved in various DNA repair pathways (NHEJ, HR and Fanconi anemia pathway; KEGG pathway database) are described. We identified 32 DEGs (14 upregulated and 18 downregulated) with these neuroblastoma cell lines. USP22 and USP41 DUBs and its differential expression in these cell lines denotes the importance of such analysis. Especially considering USP22 a potentially biomarker for predicting the outcome of patients with neuroblastoma. These DEG-DUBs were likewise correlated with 91 DNA damage response (DDR) genes belonging to three different pathways (NHEJ, HR and Fanconi anemia pathway). Out of which 44 of the DDR genes showed significant correlation with DEG-DUBs. Further studies are needed to determine the mechanisms underlying the complex relationship of these DUBs and to determine the critical DUBs for drug targeting and to enhance the efficacy of radiation therapy in cancer treatment. Citation Format: Vaibhav Vaibhav, Fahika Nazeerulla, Tatjana Paunesku, Ekta Tripathi, Gayle Woloschak, Prashanthi Karyala, Rao V. Papineni. Differential expression of deubiquitinating enzymes and its related DNA damage response genes in neuroblastoma heterogeneity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB015.

The Japanese breast cancer society clinical practice guidelines for radiation treatment of breast cancer, 2022 edition.

The Breast Cancer Clinical Practice Guidelines, organized by the Japanese Breast Cancer Society (JBCS), were published in 2022. We present the English version of the Radiation Therapy (RT) section of the guidelines. The JBCS formed a task force to update the 2018 version of the JBCS Clinical Practice Guidelines. The Background Questions (BQs) contain the standard treatments for breast cancer in clinical practice, whereas the Clinical Questions (CQs) address daily clinical questions that remain controversial. Future Research Questions (FRQs) explore the subjects that are considered important issues, despite there being insufficient data for inclusion as CQs. The task force selected the 12 BQs, 8 CQs, and 6 FRQs for the RT section. For each CQ, systematic literature reviews and meta-analyses were conducted according to the Minds Manual for Guideline Development 2020, version 3.0. The recommendations, strength of recommendation, and strength of evidence for each CQ were determined based on systematic reviews and meta-analyses, and finalized by voting at the recommendation decision meeting.

Oncological and functional outcomes for transoral robotic surgery following previous radiation treatment for upper aerodigestive tract head and neck cancers. A French multicenter GETTEC group study.

Transoral robotic surgery (TORS) opens new perspectives. We evaluated the outcomes for patients having undergone TORS after previous radiotherapy. A retrospective multicenter study (n = 138) in a previously irradiated area between 2009 and 2020. Survival was assessed with the Kaplan-Meier method. Prognostic factors were evaluated using a chi-squared test, Fisher's test, or Wilcoxon's test. The median length of hospital stay was 12.5 days. Bleeding was the most frequent postoperative complication (15.2%, n = 22). Prophylactic vessel ligation did not significantly decrease bleeding. Complications were significantly lower for Tis, T1, and N0 tumors. 91.6% (n = 120) of the patients with a perioperative tracheotomy could be decannulated. Larynx was functional for 65.94% of the patients. The median length of follow-up was 26 months. The 5-year overall and relapse-free survival rates were respectively 59.9% and 43.4%. Oncological and functional results confirmed the value of TORS as a treatment in previously irradiated area.

Exploration of the method and efficacy of treatments for intractable pelvic pain caused by rectal or bladder fistula

Objective: To explore the causes and therapeutic effects of pelvic pain caused by rectal fistula or bladder fistula after comprehensive treatment of cervical cancer and rectal cancer (radiotherapy, surgery, chemotherapy, and other treatments). Methods: A retrospective analysis was conducted on the clinical and pathological data of patients with pelvic tumors admitted to the First People's Hospital of Yinchuan City, Ningxia and the Affiliated Cancer Hospital of Zhengzhou University from June 2016 to June 2022. The causes of persistent pelvic pain in patients after comprehensive treatment was investigated, and the corresponding therapeutic effects after clinical treatment was observed. Results: Thirty-two tumor patients experienced persistent pain after comprehensive treatment, including 22 cases of cervical cancer and 10 cases of rectal cancer. The preoperative pain of the entire group of patients was evaluated using the digital grading method, with a pain score of (7.88±1.31) points. Among the 32 patients, there were 16 cases of rectovaginal fistula or ileovaginal fistula, 9 cases of vesicovaginal fistula, 5 cases of rectoperineal fistula, and 2 cases of vesicovaginorectal fistula. Thirty-two patients were initially treated with medication to relieve pain, and according to the ruptured organs, a fistula was made to the corresponding proximal intestinal canal and renal pelvis to intercept the intestinal contents and urine. However, the pain did not significantly be improved. The pain score of treatment with the above methods for one week was (8.13±1.13) points, and there was no statistically significant difference compared to preoperative treatment (P=0.417). In the later stage, based on a comprehensive evaluation of whether the tumor had recurred, the value of organ preservation, the benefits of surgery, the balance between survival time and improving quality of life, pathological organ resection or repair was performed. The surgical methods included repair of leaks, local debridement combined with irrigation of proximal intestinal fluid, distal closure of the sigmoid colon combined with proximal ostomy, posterior pelvic organ resection, anterior pelvic organ resection, and total pelvic organ resection. One week after surgery, the patients' pain completely relieved or disappeared, with the pain score of (1.72±1.37) points, which was significantly divergent from the preoperative and initial surgical treatments (P＜0.001). Conclusions: Palliative pyelostomy and proximal enterostomy cannot effectively alleviate persistent pelvic floor pain. The fundamental way to alleviate pain is complete blocking of the inflammatory erosion of the intestinal fluid and urine.

Abstract 7128: Novel Ku-DNA binding inhibitors impact on the cellular and in vivo DNA damage response to radio- and radiomimetic-therapy

Abstract DNA-PK, the DNA-dependent protein kinase, is a validated target for cancer therapeutics that plays a central role in the non-homologous end joining (NHEJ) DNA repair pathway and the DNA damage response (DDR). NHEJ is a key mechanism of DNA double-strand breaks (DSB) repair, especially those induced by ionizing radiation (IR). Ku 70/80 heterodimer is required as initiator in this process, acting as an essential DNA-binding component of DNA-PK that senses DNA damage. Blocking the DNA-PK kinase activity in combination with DSB inducing agents has been widely used as a therapeutic strategy to drive clinical efficacy of radiation therapy for cancer treatment. We have reported a unique approach of DNA-PK inhibition by developing Ku-DNA binding inhibitors (Ku-DBi’s), small molecule inhibitors that target the interaction between Ku70/80 and DNA. Ku-DBi’s demonstrated a direct interaction with Ku70/80, a potent inhibition of Ku-DNA binding and DNA-PK catalytic activity, and in vitro and cellular NHEJ inhibitory activity. This results in the potentiation of non-small cell lung cancer (NSCLC) cellular sensitivity to DSB generating therapies, as a function of inhibiting DNA-PKcs autophosphorylation and dysregulation of signaling to the DDR. In this study, we have expanded our structure activity relationship analyses to focus on optimizing selectivity, cellular uptake and Ku inhibitory activity. The new series of Ku-DBi’s include oxindole derivatives of the X80 core structure that achieve these goals. These novel compounds display increased cellular uptake while retaining potent Ku inhibitory activity and enhanced cellular inhibition on DNA-DSB repair. Ku-DBi’s optimization has enabled in vivo analyses of Ku-DBi - ionizing radiation combination therapy in human xenograft models of non-small cell lung cancer. The impact of Ku-DBi treatment on therapeutic efficacy, toxicity, Ku/DNA-PK inhibition, and DDR signaling will be presented. These data represent a significant advance in the development of Ku-DNA binding inhibitors and their therapeutic intervention for cancer treatment. Citation Format: Pamela L. Mendoza-Munoz, Dineshsinha Chauhan, Navnath S. Gavande, Joseph R. Dynlacht, Joy E. Garrett, John J. Turchi. Novel Ku-DNA binding inhibitors impact on the cellular and in vivo DNA damage response to radio- and radiomimetic-therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7128.

Isoform Switching Regulates the Response to Ionizing Radiation Through SRSF1

This study investigated how isoform switching affects the cellular response to ionizing radiation (IR), an understudied area despite its relevance to radiation therapy in cancer treatment. We aimed to identify changes in transcript isoform expression post-IR exposure and the proteins mediating these changes, with a focus on their potential to modulate radiosensitivity. Using RNA sequencing, we analyzed the B-cell lines derived from 10 healthy individuals at 3 timepoints, applying the mixture of isoforms algorithm to quantify alternative splicing. We examined RNA binding protein motifs within the sequences of IR-responsive isoforms and validated the serine/arginine-rich splicing factor 1 (SRSF1) as a predominant mediator through RNA immunoprecipitation. We further investigated the effects of SRSF1 on radiosensitivity by RNA interference and by analyzing publicly available data on patients with cancer. We identified ∼1900 radiation-responsive alternatively spliced isoforms. Many isoforms were differentially expressed without changes in their overall gene expression. Over a third of these transcripts underwent exon skipping, while others used proximal last exons. These IR-responsive isoforms tended to be shorter transcripts missing vital domains for preventing apoptosis and promoting cell division but retaining those necessary for DNA repair. Our combined computational, genetic, and molecular analyses identified the proto-oncogene SRSF1 as a mediator of these radiation-induced isoform-switching events that promote apoptosis. After exposure to DNA double-strand break-inducing agents, SRSF1 expression decreased. A reduction in SRSF1 increased radiosensitivity in vitro and among patients with cancer. We establish a pivotal role for isoform switching in the cellular response to IR and propose SRSF1 as a promising biomarker for assessing radiation therapy effectiveness.