Radiotherapy Research Articles

P055 Dosimetric benefits of CT-based online adaptive radiotherapy in stereotactic body radiation therapy for prostate cancer

P055 Dosimetric benefits of CT-based online adaptive radiotherapy in stereotactic body radiation therapy for prostate cancer

P089 PSMA-targeted focal stereotactic re-irradiation in two fractions for recurrent prostate cancer post-definitive radiation therapy

P089 PSMA-targeted focal stereotactic re-irradiation in two fractions for recurrent prostate cancer post-definitive radiation therapy

P050 Real-world risk of death from cardiovascular disease, prostate cancer, and other causes in patients treated with radical prostatectomy or definitive radiation therapy for high-risk prostate cancer

P050 Real-world risk of death from cardiovascular disease, prostate cancer, and other causes in patients treated with radical prostatectomy or definitive radiation therapy for high-risk prostate cancer

P070 Clinical and treatment factors associated with PSA bounce or recurrence: Decoding a rising PSA after radiation therapy for prostate cancer

P070 Clinical and treatment factors associated with PSA bounce or recurrence: Decoding a rising PSA after radiation therapy for prostate cancer

Ten-Year Outcome After Supracricoid Partial Laryngectomy in cT3M0 Laryngeal Squamous Cell Carcinoma-A STROBE Analysis.

The aim of this study was to document 10-year outcomes after supracricoid partial laryngectomy (SCPL) in selected cT3M0 laryngeal squamous cell carcinoma (SCC) patients. This real-life retrospective observational study analyzed an inception cohort of 168 patients with isolated, untreated, selected cT3M0 laryngeal SCC, that were consecutively managed by SCPL during the period 1973-2013, and followed up until death or for a minimum of 10 years in 92% of cases at a single French academic and tertiary referral care center. Prior induction chemotherapy, arytenoid cartilage removal, level II-IV neck dissection, and postoperative radiation therapy were performed on 148, 77, 136, and 27 patients, respectively. The main objective was to determine 10-year actuarial local control and laryngeal preservation estimates. Secondary objectives included 10-year actuarial survival and cause-of-death analysis, and assessment of correlations between endpoints and clinical variables. The significance threshold was set at p < 0.005. Ten-year actuarial local control, laryngeal preservation, and survival estimates were 90%, 85%, and 52%, respectively. Salvage treatment resulted in an overall 99% local control rate. Metachronous second primary cancer, intercurrent disease without evidence of SCC, SCPL-related death, and uncontrolled local recurrence accounted for 31%, 26%, 7%, and 2% of causes of death. On univariate analysis, overall local recurrence and laryngeal preservation rates varied significantly, from 5% to 54% and 90% to 46% when resection margins were R0 and R1, respectively. The present study highlighted successful 10-year outcomes after SCPL, providing further evidence in favor of its integration into the conservative armamentarium for endolaryngeal cT3 SCC. 4 Laryngoscope, 134:4557-4563, 2024.

PSOR06 Presentation Time: 11:55 AM: Focal Intraprostatic Boost in Patients with Localized Prostate Cancer: High Dose Rate Brachytherapy versus External Beam Radiation Therapy

PSOR06 Presentation Time: 11:55 AM: Focal Intraprostatic Boost in Patients with Localized Prostate Cancer: High Dose Rate Brachytherapy versus External Beam Radiation Therapy

Nanozymes as Glucose Scavengers and Oxygenerators for Enhancing Tumor Radiotherapy.

Insufficient accumulation of reactive oxygen species (ROS) due to tumor hypoxia significantly contributes to increased radiation resistance and the failure of radiotherapy (RT). Therefore, developing methods to alleviate hypoxia and boost ROS levels represents a promising strategy for enhanced radiosensitivity. This study introduced a self-cascade catalytic Pt@Au nanozymes as a radiosensitizer, using glucose oxidase (GOx)-, catalase (CAT)-, and peroxidase (POD)-like activities to improve hypoxia and increase ROS accumulation, thereby affecting glucose metabolism and enhancing the effects of RT. Pt@Au nanozymes exhibit GOx-like activity, which not only depletes glucose to induce starvation therapy, but also generates hydrogen peroxide (H2O2) for cascade reactions. Moreover, Pt@Au nanozymes demonstrate CAT-like activity, catalyzing the conversion of H2O2 to O2. This conversion effectively alleviates hypoxia, stabilizes ROS, increases DNA damage, significantly enhancing RT efficacy and sustaining the effects of starvation therapy. As high-Z materials, Pt@Au nanozymes can deposit more X-ray energy. Furthermore, the POD-like activity catalyzes the conversion of H2O2 into highly reactive hydroxyl radicals (·OH), which increases ROS levels and enhances RT. Pt@Au nanozymes serve as X-ray computed tomography (CT) imaging agents, allowing for clear differentiation between tumor and normal tissue boundaries and enhancing the precision of RT. In summary, Pt@Au nanozymes serve as effective radiosensitizers by depleting glucose to induce starvation therapy, enhancing cascade reactions, and inhibiting tumor proliferation. Through their self-cascade reactions, these nanozymes dramatically increase oxygen levels within tumors, reduce hypoxia, and enhance ROS levels. This advancement addresses the radioresistance associated with hypoxic tumors, paving the way for innovative strategies in RT.

Nanocarrier Delivery of Cisplatin and its Patent Studies

Cisplatin, also known as cis-(diammine) dichloridoplatinum (II) or CDDP, is frequently used as first-line chemotherapy in head, neck, and lung malignancies. It can be given as a single agent or in conjunction with radiation therapy and/or other anti-cancer chemotherapeutic agents. Now, experiences based on PEGylated liposome-based nano-formulations AroplatinTM, LipoplatinTM, and SPI-077 are undergoing clinical trials. These cisplatin drug delivery systems resolve issues like poor solubility in water, drug resistance, and toxicity by using nanocarrier systems. The above-cited nano-delivery technologies for cisplatin have been extensively described in numerous pieces of literature existing in various databases. Essentially, this evaluation gives a severe focus on newer information, invented news, and up-to-date articles regarding various carrier systems for CDDP and the newer patents of this drug formulation.

Potential Strategies for Overcoming Drug Resistance Pathways Using Propolis and Its Polyphenolic/Flavonoid Compounds in Combination with Chemotherapy and Radiotherapy

Conventional cancer treatments include surgical resection, chemotherapy, hyperthermia, immunotherapy, hormone therapy, and locally targeted therapies such as radiation therapy. Standard cancer therapies often require the use of multiple agents, which can activate nuclear factor kappa B (NF-κB) in tumor cells, leading to reduced cell death and increased drug resistance. Moreover, the use of multiple agents also contributes to added toxicity, resulting in poor treatment outcomes. Cancer cells gradually develop resistance to almost all chemotherapeutics through various mechanisms, such as drug efflux, alterations in drug metabolism and transport, changes in signal transduction pathways, enhanced DNA repair capacity, evasion of apoptosis, increased mutations, reactivation of drug targets, interaction with the cancer microenvironment, cancer cell-stroma interactions, epithelial–mesenchymal transition (EMT)-mediated chemoresistance, epigenetic modifications, metabolic alterations, and the effect of cancer stem cells (CSCs). Developing new strategies to improve chemotherapy sensitivity while minimizing side effects is essential for achieving better therapeutic outcomes and enhancing patients’ quality of life. One promising approach involves combining conventional cancer treatments with propolis and its flavonoids. These natural compounds may enhance tumor response to treatment while reducing toxicity. Propolis and its components can sensitize cancer cells to chemotherapeutic agents, likely by inhibiting NF-κB activation, reprogramming tumor-associated macrophages (TAMs; an M2-like phenotype), and thereby reducing the release of matrix metalloproteinase (MMP)-9, cytokines, chemokines, and the vascular endothelial growth factor (VEGF). By reducing TAMs, propolis and its components may also overcome EMT-mediated chemoresistance, disrupt the crosstalk between macrophages and CSCs, inhibit the maintenance of stemness, and reverse acquired immunosuppression, thus promoting an antitumor response mediated by cytotoxic T-cells. This review highlights the potential of flavonoids to modulate the responsiveness of cancer to conventional treatment modalities. The evidence suggests that novel therapeutic strategies incorporating flavonoids could be developed to improve treatment outcomes. The positive effects of combining propolis with chemotherapeutics include reduced cytotoxicity to peripheral blood leukocytes, liver, and kidney cells. Therefore, polyphenolic/flavonoid components may hold potential for use in combination with chemotherapeutic agents in the clinical treatment of various types of cancers.

Incidence of malignant neoplasms and organizational aspects of cancer care in the Republic of Kazakhstan

BackgroundThis study aims to investigate the incidence and mortality rates of malignant neoplasms in Kazakhstan in 2022 and to analyze the organizational aspects of cancer care. MethodsData from 33,177 patients with malignant neoplasms registered in oncological institutions in 2022 were analyzed. The study focused on treatment completion rates and the distribution of treatment modalities, including surgical, radiation, medicinal, combined, comprehensive, and chemo-radiation therapies. Comparative analysis with international data was conducted to assess the effectiveness and adherence to global oncological standards. ResultsThe analysis revealed that 55.2 % of patients completed specialized treatment, with complex treatment being the most common modality (94.3 %). High completion rates were observed in breast cancer (65.9 %) and cervical cancer (68.8 %), reflecting the effectiveness of early detection and multidisciplinary approaches. However, lower completion rates were noted in liver cancer (26.2 %) and leukemia (23.0 %), highlighting the need for improved diagnostic and treatment strategies. Comparative international data indicated similar trends, with countries like the USA, UK, Japan, and Australia demonstrating the effectiveness of multidisciplinary and comprehensive treatment approaches. ConclusionThe study underscores the importance of a multidisciplinary approach in treating malignant neoplasms, with Kazakhstan's practices largely aligning with international standards. Nevertheless, there is a need to enhance early diagnosis and treatment completion rates for specific cancers such as liver cancer and leukemia. Strengthening screening programs, improving access to modern treatments, and integrating international best practices can further improve patient outcomes in Kazakhstan.

Diagnostics and Screening in Breast Cancer with Brain and Leptomeningeal Metastasis: A Review of the Literature

Brain and leptomeningeal metastases are complications of breast cancer with high rates of morbidity and mortality and have an estimated incidence of up to 30%. While National Comprehensive Cancer Network (NCCN) guidelines recommend screening for central nervous system metastasis in other neurotropic cancers such as non-small cell lung cancer, there are no such recommendations for asymptomatic breast cancer patients at any stage of disease. This review highlights ongoing studies into screening and diagnostics for breast cancer with brain and leptomeningeal metastasis (BCBLM) as they relate to patient outcomes and prognostication. These include imaging methods such as MRI with novel contrast agents with or without PET/CT, as well as ‘liquid biopsy’ testing of the cerebrospinal fluid and serum to analyze circulating tumor cells, genomic material, proteins, and metabolites. Given recent advances in radiation, neurosurgery, and systemic treatments for BCBLM, screening for CNS involvement should be considered in patients with advanced breast cancer as it may impact treatment decisions and overall survival.

Comprehensive Review of the Utility of Dynamic Contrast-Enhanced MRI for the Diagnosis and Treatment Assessment of Spinal Benign and Malignant Osseous Disease.

Conventional MRI is currently the preferred imaging technique for detection and evaluation of malignant spinal lesions. However, this technique is limited in its ability to assess tumor viability. Unlike conventional MRI, dynamic contrast-enhanced (DCE) MRI provides insight into the physiologic and hemodynamic characteristics of malignant spinal tumors and has been utilized in different types of spinal diseases. DCE has been shown to be especially useful in the cancer setting; specifically, DCE can discriminate between malignant and benign vertebral compression fractures as well as between atypical hemangiomas and metastases. DCE has also been shown to differentiate between different types of metastases. Furthermore, DCE can be useful in the assessment of radiation therapy for spinal metastases, including the prediction of tumor recurrence. This review considers data analysis methods utilized in prior studies of DCE-MRI data acquisition and clinical implications.

Response of Spontaneous Oral Tumors in Canine Cancer Patients Treated with Stereotactic Body Radiation Therapy (SBRT).

To describe outcome and toxicity for dogs with oral tumors, specifically oral malignant melanoma (OMM), squamous cell carcinoma (SCC), and soft tissue sarcoma (STS) after stereotactic body radiation therapy (SBRT). A single institution retrospective study was conducted. Outcomes were analyzed using Kaplan-Meier analysis and Cox proportional hazard analysis. Treatment responses at different time points were evaluated with Pearson's Chi-squared test to identify prognostic factors. Acute and late toxicities were recorded according to VRTOG criteria and were analyzed to identify risk factors. Adverse events other than acute and late toxicities were recorded. A total of 98 patients met the inclusion criteria (OMM n = 37; SCC n = 18; STS n = 43). The SBRT prescription was 1-6 fractions, with a total dose range of 12-40 Gy. Local progression-free survival (PFS) for OMM, SCC, and STS was 187, 253, and 161 days, respectively. Overall PFS was 152 days and median survival time (MST) was 270 days, with no statistical difference between tumor types. The presence of lymph node metastasis and the use of elective nodal irradiation (ENI) were associated with shorted PFS and MST. Severe acute toxicities to organs at risk affected 10/85 (11.8%) of patients. Osteoradionecrosis and oronasal fistula formation occurred in 23/81 (28.4%) of patients and was significantly associated with tumor type (SCC, P = 0.006). BRT can be offered as a treatment option for oral tumors in dogs. Toxicities were common and warrant risk factor considerations and adjustments to current SBRT protocols.

Forecasting Daily Radiotherapy Patient Volumes in a Tertiary Hospital Using Autoregressive Integrated Moving Average (ARIMA) Models.

The purpose is to predict the volume of patients treated daily with radiotherapy using the autoregressive integrated moving average (ARIMA) model. In this retrospective study, data from the billing records detailing daily radiotherapy treatment sessions were extracted from the Hospital Information System and analyzed. The study included all patients treated from January 2004 to December 2022. The analysis was divided into two parts: First, the data were summarized using descriptive statistics. Second, time series forecasting with the implementation of an ARIMA model for estimating patient volumes. For the ARIMA modeling process, the Akaike Information Criterion (AIC) was used for classical model optimization. The Mean Absolute Percentage Error (MAPE) was used for evaluating between different models. Residual analysis was performed in each model using the Ljung-Box test, Jarque-Bera test, and heteroskedasticity test to identify autocorrelation, normal distribution, and variances that could undermine the reliability of the model. A total of 895,808 radiotherapy sessions were included in the study. The median number of radiotherapy sessions per day was 181 (150, 205). A clear transition to more modern radiotherapy equipment, particularly the Truebeam accelerator, was observed, indicating a growing dependency on advanced techniques such as volumetric-modulated arc therapy (VMAT), stereotactic body radiation therapy (SBRT), and stereotactic radiosurgery (SRS). The best ARIMA model predicted an increase in demand, projecting an average daily patient volume of 279.40 by 2030. The study highlights the need for advanced forecasting methodologies in healthcare resource planning and emphasizes the importance of considering environmental and external factors for effective and accurate resource allocation strategies.

Current Management of Pediatric Patients with Post-Burn Scars: Case Study

Background. Post-burn scars are common among pediatric patients. Pathological scarring is clear indication for conservative or surgical management of pediatric patients who continue to grow and develop after the resolution of burn injuries. Such lesions can significantly reduce patients' quality of life and, moreover, cause significant functional and aesthetic discomfort. Clinical cases description. The results of observation over two children (2 years 7 months and 12 years) with developing post-burn scars are demonstrated. Successful management method using physiotherapeutic complex (including monopolar radiofrequency treatment combined with ultrasound therapy, photodynamic therapy, and close-focus X-ray therapy) is presented. Conclusion. Modern trends in post-burn scars management are based on timely implementation of effective and safe methods early on rehabilitation stages and tissue restoration after burn injury to prevent pathological scarring and achieve control over its activity.

Survival and Toxicity Outcomes with Radiotherapy Technique and Timing in the Management of Wilms Tumor: a Systematic Review to Inform a National Clinical Practice Guideline Development

Purpose: Wilms tumor (WT) management has evolved into a multimodality paradigm that includes radiotherapy (RT), usually as an adjuvant or consolidative modality. Protocols are refined to maximize cure and compliance while minimizing acute toxicity and long-term effects. RT technique and timing are two factors that could improve these outcomes. We reviewed the evidence on survival and toxicity outcomes among WT patients with conventional versus advanced RT techniques and early versus delayed RT to inform a Department of Health (DOH) commissioned guideline. Materials and Methods: We systematically searched PubMed, EuropePMC, EBSCOHost, HERDIN, systematic review and clinical trial registries and official websites of scientific societies for relevant publications and grey literature. Eligibility screening, risk-of-bias assessment and data extraction were performed using a single-reviewer approach. Given the study and data heterogeneity, only a qualitative synthesis was performed. Certainty of evidence assessment was done using the GRADE approach. Results: We screened 314 studies and included seven in the review, including a phase 1/2 trial and six retrospective studies, all from first-world countries (US, France, Netherlands), except one from a newly industrialized country (Brazil). The certainty of evidence on the survival and toxicity outcomes with advanced RT techniques was very low. Moderate-certainty evidence supports that giving RT &gt;14 days after surgery leads to increased mortality. Conclusion: Current evidence does not support the routine use of advanced RT techniques; proper contextualization is necessary. Tertiary centers managing WT should strive to administer RT within 14 days after surgery whenever possible. Keywords: Wilms tumor, nephroblastoma, radiotherapy, intensity-modulated radiotherapy, survival, toxicity

Combined Radiotherapy and Hyperthermia: A Systematic Review of Immunological Synergies for Amplifying Radiation-Induced Abscopal Effects

Introduction: The abscopal effect is a systemic immune response characterized by metastases regression at sites distant from the irradiated lesion. This systematic review aims to explore the immunological mechanisms of action underlying the abscopal effect and to investigate how hyperthermia (HT) can increase the chances of radiotherapy (RT) triggering systemic anti-tumor immune responses. Methods: This review is created in accordance with the PRISMA guidelines. Results and Conclusion: HT and RT have both complementary and synergistic immunological effects. Both methods trigger danger signal release, promoting cytokine and chemokine secretion, which increases T-cell infiltration and facilitates cell death. Both treatments upregulate extracellular tumor HSP70, which could amplify DAMP recognition by macrophages and DCs, leading to stronger tumor antigen presentation and CTL-mediated immune responses. Additionally, the combined increase in cell adhesion molecules (VCAM-1, ICAM-1, E-selectin, L-selectin) could enhance leukocyte adhesion to tumors, improving lymphocyte trafficking and boosting systemic anti-tumor effects. Lastly, HT causes vasodilation and improves blood flow, which might exacerbate those distant effects. We suggest the combination of local radiotherapy with fever-range whole-body hyperthermia to optimally enhance the chances of triggering the abscopal effect mediated by the immune system.

Development of a web-based tool for estimating individualized survival curves in glioblastoma using clinical, mRNA, and tumor microenvironment features with fusion techniques.

Glioblastoma (GBM), one of the most common brain tumors, is known for its low survival rates and poor treatment responses. This study aims to create a robust predictive model that integrates multiple feature types, including clinical data, RNA expression, and tumor microenvironment data, using fusion techniques to enhance model performance. We obtained data from the SEER database to assess the impact of nine demographic and clinical features on the survival of 58,495 GBM patients and built predictive machine learning models. Additionally, mRNA expression data from 600 GBM patients from TCGA, CGGA, and GEO were analyzed. We used Cox regression and LASSO to create a gene signature, which was compared against 13 published signatures for accuracy. Twenty-one machine learning models were applied to predict survival at multiple time points. Finally, we integrated multiple feature types using fusion techniques and developed a Shiny app to provide survival predictions for GBM patients. Using the SEER database, we constructed machine learning models based on nine clinical variables: age, gender, marital status, race, tumor site, laterality, surgery, chemotherapy, and radiation therapy. The best-performing model achieved AUC values of 0.775, 0.728, 0.692, and 0.683 for predicting survival at 6, 12, 18, and 24months in the testing cohort. In the merged TCGA, CGGA, and GEO cohorts, we identified 11 genes to develop predictive models. These 11 genes outperformed 13 other published gene signatures in predicting the prognosis of GBM. When incorporating mRNA features, tumor microenvironment features, and clinical variables into the fusion models, the AUC values for predicting survival at 6, 12, 18, and 24months were 0.641, 0.624, 0.655, and 0.637, respectively. A user-friendly tool for predicting the survival curve of individual GBM patients is available at https://zzubioinfo.shinyapps.io/mlGBM/ . Our study provides a web-based tool that includes two modules: one for predicting survival curves using only clinical variables, and another that integrates multiple feature types for more comprehensive predictions.

Automated Organ Segmentation for Radiation Therapy: A Comparative Analysis of AI-Based Tools Versus Manual Contouring in Korean Cancer Patients

Background: Accurate delineation of tumors and organs at risk (OARs) is crucial for intensity-modulated radiation therapy. This study aimed to evaluate the performance of OncoStudio, an AI-based auto-segmentation tool developed for Korean patients, compared with Protégé AI, a globally developed tool that uses data from Korean cancer patients. Methods: A retrospective analysis of 1200 Korean cancer patients treated with radiotherapy was conducted. Auto-contours generated via OncoStudio and Protégé AI were compared with manual contours across the head and neck and thoracic, abdominal, and pelvic organs. Accuracy was assessed using the Dice similarity coefficient (DSC), mean surface distance (MSD), and 95% Hausdorff distance (HD). Feedback was obtained from 10 participants, including radiation oncologists, residents, and radiation therapists, via an online survey with a Turing test component. Results: OncoStudio outperformed Protégé AI in 85% of the evaluated OARs (p &lt; 0.001). For head and neck organs, OncoStudio achieved a similar DSC (0.70 vs. 0.70, p = 0.637) but significantly lower MSD and 95% HD values (p &lt; 0.001). In thoracic organs, OncoStudio performed excellently in 90% of cases, with a significantly greater DSC (male: 0.87 vs. 0.82, p &lt; 0.001; female: 0.95 vs. 0.87, p &lt; 0.001). OncoStudio also demonstrated superior accuracy in abdominal (DSC 0.88 vs. 0.81, p &lt; 0.001) and pelvic organs (male: DSC 0.95 vs. 0.85, p &lt; 0.001; female: DSC 0.82 vs. 0.73, p &lt; 0.001). Clinicians favored OncoStudio in 70% of cases, with 90% endorsing its clinical suitability for Korean patients. Conclusions: OncoStudio, which is tailored for Korean patients, demonstrated superior segmentation accuracy across multiple anatomical regions, suggesting its suitability for radiotherapy planning in this population.

Real world data on cervical cancer treatment patterns, healthcare access and resource utilization in the Brazilian public healthcare system.

The aim of the study is to evaluate the treatment patterns, time to start treatment, and healthcare resources utilization (HCRU) of cervical cancer (CC) patients within the Brazilian public health system (SUS). This is an observational retrospective study using SUS administrative database (DATASUS). Data from January-2014 to December-2020 was gathered from patients with the ICD-10 C53 codes. From 2014 to 2020, 206,861 women were included, among whom 90,073 (43.5%) had stage information. Of staged patients, 60.7% (54,719) had advanced disease (stages III and IV) and the most performed treatments were chemoradiotherapy (CRT) (41.6%), surgery + CRT (19.1%), radiotherapy (RT) only (16.8%) and chemotherapy (CT) only (13.3%). The proportion of patients submitted to CT in advanced stages was higher than in non-advanced stages (I and II), in contrast to RT, which was more frequent in stage I than stage IV. Median time to initiate treatment surpassed two months in approximately 30% of the cases, regardless of stage. Conization was the most performed surgical procedure. The hospitalization rate per patient per month for stage IV was twice as high as stage I (0.05 [95%CI 0.05-0.05] and 0.11 [0.11-0.11], respectively). The same trend was observed for outpatient visits (0.54 [95%CI 0.53-0.55] and 0.96 [0.93-0.98], respectively). This study demonstrated a high proportion of advanced CC at diagnosis in Brazil. The treatment pattern showed that chemoradiotherapy was the most frequent regimen overall and the use of chemotherapy and HCRU increased with staging. These results could provide information to improve public policies towards access to prevention, diagnosis, and treatment of CC in Brazil.