Use Of Radiotherapy Research Articles

Metastatic site radiation therapy for Ewing sarcoma and rhabdomyosarcoma: Consensus guidelines from the National Pediatric Cancer Foundation

BackgroundDespite the urgent need for improved outcomes in patients with metastatic Ewing sarcoma (EWS) and rhabdomyosarcoma (RMS), it is unknown how to best approach metastatic site radiation therapy for these patients and whether such treatment provides a significant oncologic benefit that outweighs the toxicities. MethodsWe gathered a panel of pediatric radiation oncologists from academic hospitals to identify and discuss current controversies regarding the role of radiation in the management of metastatic EWS and RMS. The panel reviewed existing clinical data and ongoing trials to address five key questions: 1) the role of whole lung irradiation (WLI) in treating lung metastases 2) number of metastatic sites warranting radiotherapy and the radicality of such an approach; 3) radiation techniques, including stereotactic body radiation therapy (SBRT); 4) the timing of metastatic-site radiation therapy; and 5) the utility of metastatic site radiation therapy for relapsed metastatic disease. ResultsAfter a review of existing data, consensus recommendations were developed to support the decision-making process in metastatic-site irradiation with the goal of improving long-term disease control. Patients with pulmonary metastases should receive WLI. In patients with limited (<8 sites) metastatic disease, a comprehensive approach should be taken to treat all sites of metastatic disease diagnosed at presentation. SBRT should be considered as a preferred treatment technique. The timing of metastatic-site treatment should coincide with the end of systemic therapy. However, if there is a dosimetric advantage or improved compliance, concurrent treatment with the primary site may be preferred. ConclusionsA consensus guideline was established to address several critical questions regarding the role of radiation in the treatment of metastatic EWS and RMS. The study highlights the existing controversies, provides a structured approach, and underscores the need for future studies to further evaluate the therapeutic ratio of metastatic-site directed therapy.

Using Deauville Scoring to Guide Consolidative Radiotherapy in Diffuse Large B-Cell Lymphoma

Background: The most common aggressive lymphoma in adults is diffuse large B-cell lymphoma (DLBCL). Consolidative radiotherapy (RT) is often administered to DLBCL patients but guidelines remain unclear, which could lead to unnecessary RT. We aimed to evaluate the value of end-of-treatment PET-CT scans, interpreted using the Deauville score (DV), to guide the utilization of consolidative RT, which may help spare low-risk DLBCL patients from unnecessary RT. Methods: We included all DLBCL patients diagnosed between 2010 and 2022 at the National Cancer Centre Singapore with DV measured at the end of the first-line chemoimmunotherapy. The outcome measure was time-to-progression (TTP). The predictive value of DV for RT was assessed based on the interaction effect between the receipt of RT and DV in Cox regression models. Results: The data of 349 patients were analyzed. The median follow-up time was 38.1 months (interquartile range 34.0–42.3 months). RT was associated with a significant improvement in TTP amongst the DV4-5 patients (HR 0.33; 95%CI 0.13–0.88; p = 0.027) but not the DV1-3 patients (HR 0.85; 95%CI 0.40–1.81; p = 0.671) (interaction’s p = 0.133). Multivariable analysis reported that RT was again significantly associated with improved TTP among the DV4-5 patients (adjusted HR 0.29; 95%CI 0.10–0.80; p = 0.017) but not the DV1-3 group (HR 0.86; 95%CI 0.40–1.86; p = 0.707) (interaction’s p = 0.087). Conclusion: Our results suggests that DLBCL patients with end-of-treatment PET-CT DV1-3 may not need consolidative RT. Longer follow-up and prospective randomized trials are still necessary to investigate long-term outcomes.

Evaluating the Effects of Prostate Radiotherapy Intensified with Pelvic Nodal Radiotherapy and Androgen Deprivation Therapy on Myelosuppression: Single-Institution Experience.

Prostate cancer (PCa) management commonly involves the utilization of prostate radiotherapy (PRT), pelvic nodal radiotherapy (PNRT), and androgen deprivation therapy (ADT). However, the potential association of these treatment modalities with bone marrow (BM) suppression remains inadequately reported in the existing literature. This study is designed to comprehensively evaluate the risk of myelosuppression associated with PRT, shedding light on an aspect that has been underrepresented in prior research. We conducted a retrospective analysis of 600 patients with prostate cancer (PCa) treated with prostate radiotherapy (PRT) at a single oncology center between 2007 and 2017. Patients were categorized into four cohorts: PRT alone (n = 149), PRT + ADT, (n = 91), PRT + PNRT (n = 39), and PRT + PNRT + ADT (n = 321). To assess the risk of myelosuppression, we scrutinized specific blood parameters, such as hemoglobin (HGB), white blood cells (WBCs), neutrophils (NEUT), lymphocytes (LYM), and platelets (PLT) at baseline, mid-treatment (mRT), immediately post-RT (pRT), 1 month post-RT (1M-pRT), and 1 year post-RT (1Y-pRT). The inter-cohort statistical significance was evaluated with further stratification based on the utilized RT technique {3D conformal radiotherapy (3D-CRT), and intensity-modulated radiation therapy (IMRT)}. Significant statistical differences at baseline were observed in HGB and LYM values among all cohorts (p < 0.05). Patients in the PRT + PNRT + ADT cohort had significantly lower HGB at baseline and 1M-pRT. In patients undergoing ADT, BMS had a significant impact at 1M-pRT {odds ratio (OR) 9.1; 95% Confidence Interval (CI) 4.8-17.1} and at 1Y-pRT (OR 2.84; CI 1.14-7.08). The use of 3D-CRT was linked to reduced HGB levels in the PRT + PNRT + ADT group at 1 month pRT (p = 0.015). Similarly, PNRT significantly impacted BMS at 1M-pRT (OR 6.7; CI 2.6-17.2). PNRT increased the odds of decreased WBC counts at 1Y-pRT (OR 6.83; CI: 1.02-45.82). Treatment with any RT techniques (3D-CRT or IMRT), particularly in the PRT + PNRT and PRT + PNRT + ADT groups, significantly increased the odds of low LYM counts at all time points except immediately pRT (p < 0.05). Furthermore, NEUT counts were considerably lower at 1M-pRT (p < 0.05) in the PRT + PNRT + ADT group. PLT counts were significantly decreased by PRT + PNRT + ADT at mRT (OR 2.57; 95% CI: 1.42-4.66) but were not significantly impacted by the RT technique. Treatment with PRT, ADT, PNRT, and 3D-CRT is associated with BMS. Despite this statistically significant risk, no patient required additional interventions to manage the outcome. While its clinical impact appears limited, its importance cannot be underestimated in the context of increased integration of novel systemic agents with myelosuppressive properties. Longer follow-up should be considered in future studies.

37 the Management of Stage I Non-Small Cell Lung Cancer (NSCLC) in Ontario: A Population-Based Study of Practice Patterns of Care and Stereotactic Ablative Body Radiotherapy Utilization from 2010-2019

37 the Management of Stage I Non-Small Cell Lung Cancer (NSCLC) in Ontario: A Population-Based Study of Practice Patterns of Care and Stereotactic Ablative Body Radiotherapy Utilization from 2010-2019

Pediatric intramedullary spinal cord tumors: A national cancer database analysis of demographics, patterns of care, and survival

ObjectiveQuery the National Cancer Database (NCDB) to delineate epidemiologic frequency, care patterns, and survival outcomes of pediatric intramedullary spinal cord tumors (IMSCTs). MethodsIMSCTs included ependymoma, astrocytoma, and hemangioblastoma. We examined data from the NCDB spanning 2004–2018, focusing on IMSCT in children aged 0–21 years. Our analysis included logistic and Poisson regression, Kaplan-Meier survival estimates, and Cox proportional hazards models. ResultsThis study included 1066 patients aged 0–21 years. 59.4 % of patients were male, while 83.1 % were white. The most common tumor histology was ependymoma (57.5 %), followed by astrocytoma (36.1 %) and hemangioblastoma (6.4 %). 24.9 % of patients received radiotherapy, with radiotherapy utilization being highest among patients aged 6–10 years. Chemotherapy utilization was highest in patients aged 0–5 years. 87.2 % of patients underwent surgical resection, with higher rates in patients aged 16–21 years. Overall survival did not differ significantly between resected and non-resected patients (p = 0.315). Patients in rural areas had worse OS than those in metro areas (HR = 4.42, p = 0.048). Patients with astrocytoma had worse OS compared to other histologies (HR = 2.21, p = 0.003). Astrocytoma patients were over twice as likely to have prolonged LOS compared to ependymoma patients (OR = 2.204, p < 0.001). ConclusionsIn summary, our analysis utilizing the NCDB database provides a comprehensive overview of demographics, care patterns, and outcomes for the largest cohort of pediatric IMSCTs to date. These insights underscore the complexity of managing IMSCTs and emphasize the need for tailored approaches to improve patient outcomes.

Radiotherapy-triggered reduction of platinum-based chemotherapeutic prodrugs in tumours.

Pt(II) drugs are a widely used chemotherapeutic, yet their side effects can be severe. Here we show that the radiation-induced reduction of Pt(IV) complexes to cytotoxic Pt(II) drugs is rapid, efficient and applicable in water, that it is mediated by hydrated electrons from water radiolysis and that the X-ray-induced release of Pt(II) drugs from an oxaliplatin prodrug in tumours inhibits their growth, as we show with nearly complete tumour regression in mice with subcutaneous human tumour xenografts. The combination of low-dose radiotherapy with a Pt(IV)-based antibody-trastuzumab conjugate led to the tumour-selective release of the chemotherapeutic in mice and to substantial therapeutic benefits. The radiation-induced local reduction of platinum prodrugs in the reductive tumour microenvironment may expand the utility of radiotherapy.

What's Changed in 75 Years of RadRes? - An Australian Perspective on Selected Topics.

Several scientific themes are reviewed in the context of the 75-year period relevant to this special platinum issue of Radiation Research. Two criteria have been considered in selecting the scientific themes. One is the exposure of the associated research activity in the annual meetings of the Radiation Research Society (RRS) and in the publications of the Society's Journal, thus reflecting the interest of members of RRS. The second criteria is a focus on contributions from Australian members of RRS. The first theme is the contribution of radiobiology to radiation oncology, featuring two prominent Australian radiation oncologists, the late Rod Withers and his younger colleague, Lester Peters. Two other themes are also linked to radiation oncology; preclinical research aimed at developing experimental radiotherapy modalities, namely microbeam radiotherapy (MRT) and Auger endoradiotherapy. The latter has a long history, in contrast to MRT, especially in Australia, given that the associated medical beamline at the Australian Synchrotron in Melbourne only opened in 2011. Another theme is DNA repair, which has a trajectory parallel to the 75-year period of interest, given the birth of molecular biology in the 1950s. The low-dose radiobiology theme has a similar timeline, predominantly prompted by the nuclear era, which is also connected to the radioprotector theme, although radioprotectors also have a long-established potential utility in cancer radiotherapy. Finally, two themes are associated with biodosimetry. One is the micronucleus assay, highlighting the pioneering contribution from Michael Fenech in Adelaide, South Australia, and the other is the γ-H2AX assay and its widespread clinical applications.

Fractionated radiotherapy after gross-total resection of spinal chordoma: a systematic review of survival outcomes using individualized patient data.

Spinal chordoma treatment guidelines recommend resection. However, in patients in whom gross-total resection (GTR) is achieved, the benefits of radiation therapy (RT) are unclear. Therefore, the authors performed a systematic review to determine if RT is associated with postoperative progression-free survival (PFS) or overall survival (OS) after achieving GTR of spinal chordoma. The PubMed database was searched for studies including individualized data of patients undergoing GTR with or without RT for spinal chordoma. Patients < 18 years of age or those who underwent stereotactic body RT were excluded. Qualitative assessment was performed using Newcastle-Ottawa Scale guidelines. Log-rank tests for time-to-event data and a Cox proportional-hazards model were generated for a multivariable statistical model. Complete data of 132 patients were retrieved, with 37 (28%) patients receiving adjuvant RT and 95 (72%) not receiving adjuvant RT. The mean follow-up was not statistically significantly different between those undergoing RT and not undergoing RT (54.02 months and 65.43 months, respectively). Patients were more likely not to undergo RT if their disease was located in the sacrum versus the mobile spine (p < 0.001). When controlling for age ≥ 65 years, male sex, disease location, and treatment year ≥ 2010, patients undergoing RT had similar PFS and OS when compared with those not undergoing RT on multivariable survival analysis (HR 0.935 [95% CI 0.703-2.340], p = 0.844 and HR 2.078 [95% CI 0.848-5.090], p = 0.110, respectively). However, age ≥ 65 years was associated with poorer OS in adjusted analyses (HR 2.761 [95% CI 1.185-6.432], p = 0.018) relative to patients < 65 years of age. After achieving GTR of spinal chordoma, the utility of RT on PFS and OS remains unclear. Age ≥ 65 years appears to be associated with OS in spinal chordoma patients. Additional multicenter prospective studies are needed to determine the utility of RT in this patient population.

Escalated-dose radiotherapy for unresected locally advanced pancreatic cancer: Patterns of care and survival in the United States.

With locally advanced pancreatic cancer (LAPC), uncontrolled local tumor growth frequently leads to mortality. Advancements in radiotherapy (RT) techniques have enabled conformal delivery of escalated-dose RT (EDR), which may have potential local control and overall survival (OS) benefits based on retrospective and early prospective studies. With evidence for EDR emerging, we characterized the adoption of EDR across the United States and its associated outcomes. We searched the National Cancer Database for nonsurgically managed LAPC patients diagnosed between 2004 and 2019. Pancreas-directed RT with biologically effective doses (BED10) ≥39 and ≤70 Gy was labeled conventional-dose RT (CDR), and BED10 >70 and ≤132 Gy was labeled EDR. We identified associations of EDR and OS using logistic and Cox regressions, respectively. Among the definitive therapy subset (n = 54,115) of the entire study cohort (n = 91,493), the most common treatments were chemotherapy alone (69%), chemotherapy and radiation (29%), and RT alone (2%). For the radiation therapy subset (n = 16,978), use of pancreas-directed RT remained between 13% and 17% over the study period (ptrend > 0.999). Using multivariable logistic regression, treatment at an academic/research facility (adjusted odds ratio [aOR] 1.46, p < 0.001) and treatment between 2016 and 2019 (aOR 2.54, p < 0.001) were associated with greater receipt of EDR, whereas use of chemotherapy (aOR 0.60, p < 0.001) was associated with less receipt. Median OS estimates for EDR and CDR were 14.5 months and 13.0 months (p < 0.0001), respectively. For radiation therapy subset patients with available survival data (n = 13,579), multivariable Cox regression correlated EDR (adjusted hazard ratio 0.85, 95% confidence interval 0.80-0.91; p < 0.001) with longer OS versus CDR. Utilization of EDR has increased since 2016, but overall utilization of RT for LAPC has remained at less than one in five patients for almost two decades. These real-world results additionally provide an estimate of effect size of EDR for future prospective trials.

Preexisting Diabetes and Breast Cancer Treatment Among Low-Income Women

Diabetes is associated with poorer prognosis of patients with breast cancer. The association between diabetes and adjuvant therapies for breast cancer remains uncertain. To comprehensively examine the associations of preexisting diabetes with radiotherapy, chemotherapy, and endocrine therapy in low-income women with breast cancer. This population-based cohort study included women younger than 65 years diagnosed with nonmetastatic breast cancer from 2007 through 2015, followed up through 2016, continuously enrolled in Medicaid, and identified from the linked Missouri Cancer Registry and Medicaid claims data set. Data were analyzed from January 2022 to October 2023. Preexisting diabetes. Logistic regression was used to estimate odds ratios (ORs) of utilization (yes/no), timely initiation (≤90 days postsurgery), and completion of radiotherapy and chemotherapy, as well as adherence (medication possession ratio ≥80%) and persistence (<90-consecutive day gap) of endocrine therapy in the first year of treatment for women with diabetes compared with women without diabetes. Analyses were adjusted for sociodemographic and tumor factors. Among 3704 women undergoing definitive surgery, the mean (SD) age was 51.4 (8.6) years, 1038 (28.1%) were non-Hispanic Black, 2598 (70.1%) were non-Hispanic White, 765 (20.7%) had a diabetes history, 2369 (64.0%) received radiotherapy, 2237 (60.4%) had chemotherapy, and 2505 (67.6%) took endocrine therapy. Compared with women without diabetes, women with diabetes were less likely to utilize radiotherapy (OR, 0.67; 95% CI, 0.53-0.86), receive chemotherapy (OR, 0.67; 95% CI, 0.48-0.93), complete chemotherapy (OR, 0.71; 95% CI, 0.50-0.99), and be adherent to endocrine therapy (OR, 0.71; 95% CI, 0.56-0.91). There were no significant associations of diabetes with utilization (OR, 0.95; 95% CI, 0.71-1.28) and persistence (OR, 1.09; 95% CI, 0.88-1.36) of endocrine therapy, timely initiation of radiotherapy (OR, 1.09; 95% CI, 0.86-1.38) and chemotherapy (OR, 1.09; 95% CI, 0.77-1.55), or completion of radiotherapy (OR, 1.25; 95% CI, 0.91-1.71). In this cohort study, preexisting diabetes was associated with subpar adjuvant therapies for breast cancer among low-income women. Improving diabetes management during cancer treatment is particularly important for low-income women with breast cancer who may have been disproportionately affected by diabetes and are likely to experience disparities in cancer treatment and outcomes.

Revisiting the role of radiotherapy in the treatment of neuroblastoma 4S: 30 years of institutional experience and systematic review

Background and purposeNeuroblastoma 4S is a rare subtype of metastatic neuroblastoma found in children younger than 12 months, characterized by liver, skin, or bone marrow metastases. While the prognosis for patients is generally favorable, rapid progression of liver metastases can lead to life-threatening organ insufficiency. In such cases, immediate treatment with chemotherapy or radiotherapy is necessary. Given the recent decline in radiotherapy utilization, this study aims to reassess its role, evaluating its effectiveness and toxicity. Materials and methodsWe conducted a systematic review and an institutional retrospective analysis to assess the use of radiotherapy for hepatomegaly in patients with neuroblastoma 4S. The study included data from 164 patients from the literature and 16 patients from our institutional cohort. We extracted and analyzed data on short- and long-term outcomes, as well as reports of radiotherapy-induced toxicity. ResultsOur institutional data showed that 81 % of patients responded to low-dose radiotherapy administered at a median dose of 450 cGy in three fractions, resulting in liver shrinkage and symptom resolution. Based on the systematic review, 1-year survival rate was 80 %, while 5-year survival rate was 75 %. No serious toxicity was observed with the current low-dose radiotherapy; however, one case of induced secondary malignancy was reported. ConclusionRadiation therapy is an effective treatment modality for hepatomegaly in patients with neuroblastoma 4S, with a success rate of about 80 %. Despite being administered to infants, a low dose of 450–600 cGy does not result in toxicity related to the kidneys, liver, or posture defects.

Abstract PO4-17-05: Patterns of care: radiotherapy after breast conserving surgery and the use of endocrine therapy for screen-detected ductal carcinoma in situ (DCIS) in the UK

Abstract Background The use of adjuvant radiotherapy (RT) and endocrine therapy (ET) in the management of pure ductal carcinoma in situ (DCIS) remains controversial. We investigate how the use of adjuvant RT after breast conserving surgery (BCS) and use of adjuvant ET (in BCS and mastectomy patients) has changed over time. Methods A prospective cohort SQL database of 11,284 patients (the Sloane Project) diagnosed 2003-2012 with screen-detected DCIS in the UK was interrogated for use of adjuvant RT and ET over time and association with factors reported to be predictive of recurrence (patient age, DCIS nuclear grade, size, comedo necrosis, resection margins), as well as institution of surgery, travel time to radiotherapy facility, Index of Multiple Deprivation and outcome (provided by the National Disease Registration Service, NDRS). RT data by site were confirmed with more recent data from the National Audit of Breast Cancer in Older Patients (NABCOP), which looked at patterns of care and outcomes for women aged 70 years and over, compared with those aged 50-64 in England and Wales. Results Among the 7,949 women (70.6%) treated by BCS, post-operative adjuvant RT was given to 4,939 (62.1%); RT use after BCS increased over time (R2 =0.92; p&amp;lt; 0.01). RT use was associated with year of diagnosis (p &amp;lt; 0.01), younger age at diagnosis (p &amp;lt; 0.01), larger DCIS size (p &amp;lt; 0.01), presence of comedo necrosis (p &amp;lt; 0.01), higher nuclear grade (p &amp;lt; 0.01) and presence of microinvasion (p &amp;lt; 0.01). Adjusted analyses showed the most significant factor for RT after BCS was the surgery institution. Travel time to RT facility, Index of Multiple Deprivation and final radial margin were not associated with RT use. When compared with the more recent data from the NABCOP, a marked variation in radiotherapy use across hospitals remains. Ipsilateral recurrence rate varied significantly by hospital, with some of the difference associated with RT utilisation. ET was prescribed in 1313 women (12%), more often following BCS than mastectomy (p &amp;lt; 0.001), with significant variation by institution and a decline in the use of ET over time. Conclusion Marked geographic variation in the use of RT and ET after surgery for DCIS persists in the UK and is likely due to physician choice rather than other factors such as travel times to RT facilities. This is contributing to geographic variation in ipsilateral recurrence rates, suggesting the need for adoption of more authoritative guidelines to support clinical decision-making. Consistent national practice could provide auditable performance standards for adjuvant therapy of screen detected DCIS and contribute to more uniform patient care. Citation Format: Karen Clements, David Dodwell, Elinor Sawyer, Ramsey Cutress, Nisha Sharma, Abeer Shaaban, Alastair Thompson. Patterns of care: radiotherapy after breast conserving surgery and the use of endocrine therapy for screen-detected ductal carcinoma in situ (DCIS) in the UK [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 PO4-17-05.

Assessing a Suitable Radiotherapy Utilisation Benchmark for Older Patients With Head and Neck Cancer

AimsTo (i) determine the actual radiotherapy utilization (RTU) stratified by age, (ii) develop an age- and co-morbidity adjusted optimal RTU model and (iii) examine the tolerance and toxicity of treatment of older patients with head and neck cancer. Materials and methodsA retrospective cohort study based on New South Wales Cancer Registry records (2010–2014) linked to radiotherapy data (2010–2015) and admitted patient data (2008–2015) for patients diagnosed with head and neck cancer. We calculated the actual RTU, defined as the proportion of patients who received at least one course of radiotherapy within a year of diagnosis, by age group, including patients aged 80+ years. We also calculated the age and comorbidity-adjusted optimal RTU. For treatment tolerance, the radiotherapy dose for each age group and the completion rate for a seven week 70 Gray (Gy) course of curative intent radiotherapy were computed. The number of emergency department (ED) presentations were used as a surrogate measure of acute treatment toxicity for patients receiving 70 Gy. ResultsOf the 5966 patients diagnosed with head and neck cancer, 814 (13.6%) were aged 80+ years. For all age groups, the actual RTU was less than the optimal RTU. The age- and comorbidity-adjusted optimal RTU for patients aged 80+ was 52% (95% CI: 51%–53%), and the actual RTU was 40% (95% CI: 37%–44%). Only 4.4% of patients aged 80+ received 70 Gy, and the completion rate for a 70 Gy course of radiotherapy for these patients was 92%. The ED presentation rate was similar for all age groups. ConclusionThe actual RTU was less in the 80+ years patients and across all age groups. Fewer patients in the 80+ group received curative intent schedules compared to the actual RTU rate for younger age groups, despite similar rates of completion of curative intent radiotherapy and acute toxicity.

129: Development of an Optimal Radiotherapy Utilisation Rate for Older Patients with Head and Neck Cancer

129: Development of an Optimal Radiotherapy Utilisation Rate for Older Patients with Head and Neck Cancer

Metastatic intradural primary spinal osteosarcoma: illustrative case.

Osteosarcomas are a common primary bone neoplasm among adolescents but represent 0.2% of all malignancies with an incidence of two to four cases per million persons annually worldwide. Although known to have significant metastatic potential, its rare incidence, treatment resistance, and poor prognosis have rendered it a poorly understood and infrequently documented pathology. Herein the authors present the first documented case of lumbosacral intradural metastasis of a primary osteosarcoma in a young patient, possibly via intradural dissemination following pinhole durotomy in a prior thoracic surgery. Osteosarcomas remain a difficult pathology to treat, particularly upon metastatic dissemination. The utility of adjuvant radiotherapy after resection of an osteosarcoma is increasingly evident in the reduction of local recurrence. In the context of intraoperative pinhole durotomies in resections of high-grade lesions, due consideration should be given to whole-spine radiation, although this remains an evidence-free zone.

Role of external radiation in benign tumors: A clinical outcome and safety audit of 7 years from a tertiary care center in India.

Radiotherapy (RT) is a well-established modality for treating malignancies, but its role in treatment of benign lesions has not been well explored. Herein, we present a retrospective analysis of a 7-year data regarding the benefit and the safety profile of RT for treating benign tumors in our institute. Data of 23 patients who received RT for benign tumors from January 2015 to April 2022 were retrieved, and a retrospective analysis was conducted. All the pertinent demographic data, treatment and follow-up data were retrieved. The most common presentations were nasopharyngeal angiofibroma, vertebral hemangioma, paraganglioma, and others. The most common sites of occurrence were head and neck (43%) and paravertebral region (22%). Volumetric modulated arc therapy was the most commonly employed RT technique (39%), followed by three-dimensional conformal RT (34%) and two-dimensional conventional radiotherapy (26%). The median RT dose delivered was 36 Gy (range: 20-54 Gy). The median follow-up duration was 53 months (range: 3-120 months). Nine (39%) patients had progressive disease with a median time to progression of 8 months (range: 1-30 months). The median disease-free survival (DFS) was 70 months, while the 1-, 3-, and 5-year DFS rates were 97%, 88%, and 62%, respectively. Four patients (17%) died, all due to disease progression. The 1-, 3-, and 5-year overall survival rates was 97%, 85%, and 50%, respectively. The rate of radiation-induced cancer (RIC) was 0% as none of the patients had developed RIC secondary to radiation. RT is a safe and an effective option to manage benign tumors either in an adjuvant setting or in inoperable patients requiring definitive treatment, as well as in a setting to alleviate symptoms, providing excellent survival benefits. However, further prospective studies with much higher sample size are required to establish the absolute benefit and to estimate the risk of RIC, which will further direct for a better utilization of RT in treating benign tumors.

Reducing Salivary Toxicity with Adaptive Radiotherapy (ReSTART): A Randomized Controlled Trial Comparing Conventional IMRT to Adaptive IMRT in Head and Neck Squamous Cell Carcinomas

BackgroundThe utility of Adaptive Radiotherapy (ART) in Head and Neck Squamous Cell Carcinoma (HNSCC) remains to be ascertained. While multiple retrospective and single-arm prospective studies have demonstrated its efficacy in decreasing parotid doses and reducing xerostomia, adequate randomized evidence is lacking. Methods and AnalysisReSTART (Reducing Salivary Toxicity with Adaptive Radiotherapy) is an ongoing phase III randomized trial of patients with previously untreated, locally advanced HNSCC of the oropharynx, larynx, and hypopharynx. Patients are randomized in a 1:1 ratio to the standard Intensity Modulated Radiotherapy (IMRT) arm {Planning Target Volume (PTV) margin 5 mm} vs. Adaptive Radiotherapy arm (standard IMRT with a PTV margin 3 mm, two planned adaptive planning at 10th and 20th fractions). The stratification factors include the primary site and nodal stage. The RT dose prescribed is 66Gy in 30 fractions for high-risk PTV and 54Gy in 30 fractions for low-risk PTV over six weeks, along with concurrent chemotherapy.The primary endpoint is to compare salivary toxicity between arms using salivary scintigraphy 12 months' post-radiation. To detect a 25% improvement in the primary endpoint at 12 months in the ART arm with a two-sided 5% alpha value and a power of 80% (and 10% attrition ratio), a sample size of 130 patients is required (65 patients in each arm). The secondary endpoints include acute and late toxicities, locoregional control, disease-free survival, overall survival, quality of life, and xerostomia scores between the two arms. DiscussionThe ReSTART trial aims to answer an important question in Radiation Therapy for HNSCC, particularly in a resource-limited setting. The uniqueness of this trial, compared to other ongoing randomized trials, includes the PTV margins and the xerostomia assessment by scintigraphy at 12 months as the primary endpoint.

PErspective and current status of Radiotherapy Service in IRan (PERSIR)-1 study: assessment of current external beam radiotherapy facilities, staff and techniques compared to the international guidelines

Background and purposeRadiotherapy (RT) is an essential treatment modality against cancer and becoming even more in demand due to the anticipated increase in cancer incidence. Due to the rapid development of RT technologies amid financial challenges, we aimed to assess the available RT facilities and the issues with achieving health equity based on current equipment compared to the previous reports from Iran.Materials and methodsA survey arranged by the Iran Cancer Institute's Radiation Oncology Research Center (RORC) was sent to all of the country's radiotherapy centers in 2022. Four components were retrieved: the reimbursement type, equipment, human resources, and patient load. To calculate the radiotherapy utilization rate (RUR), the Lancet Commission was used. The findings were compared with the previous national data.ResultsSeventy-six active radiotherapy centers with 123 Linear accelerators (LINACs) were identified. The centers have been directed in three ways. 10 (20 LINACs), 36 (50 LINACs), and 30 centers (53 LINACs) were charity-, private-, and public-based, respectively. Four provinces had no centers. There was no active intraoperative radiotherapy machine despite its availability in 4 centers. One orthovoltage X-ray machine was active and 14 brachytherapy devices were treating patients. There were 344, 252, and 419 active radiation oncologists, medical physicists, and radiation therapy technologists, respectively. The ratio of LINAC and radiation oncologists to one million populations was 1.68 and 4.10, respectively. Since 2017, 35±5 radiation oncology residents have been trained each year.ConclusionThere has been a notable growth in RT facilities since the previous reports and Iran's situation is currently acceptable among LMICs. However, there is an urgent need to improve the distribution of the RT infrastructure and provide more facilities that can deliver advanced techniques.

Utilization of medical interventions in hospitalized Mexican adults with cancer at the end of life in a referral hospital: The importance of early palliative care.

To investigate the impact of early vs. late palliative care (PC) on the frequency of admissions to acute hospital settings and the utilization of end-of-life (EoL) interventions in cancer decedents. In this single-center, cross-sectional study, we examined the frequency of intensive care unit (ICU) and emergency department (ED) admissions among adult cancer decedents between 2018 and 2022 in a referral hospital in México. Additionally, we assessed EoL medical interventions, categorizing patients into 3 groups: those who received early PC (EPC), late PC (LPC), and those who did not receive PC (NPC). We analyzed data from 1762 patients, averaging 56 ± 16.3 years old, with a predominant representation of women (56.8%). PC was administered to 45.2% of patients, but EPC was limited to only 12.3%. The median time from the initiation of PC to death was 5 days (interquartile range: 2.0-31.5). Hematological malignancies were the most prevalent, affecting 21.5% of patients. EPC recipients demonstrated notable reductions in ICU and ED admissions, as well as diminished utilization of chemotherapy, radiotherapy (RT), antibiotics, blood transfusions, and surgery when compared to both LPC and NPC groups. EPC also exhibited fewer medical interventions in the last 14 days of life, except for RT. The findings of this study indicate that a significant proportion of EoL cancer patients receive PC; however, few receive EPC, emphasizing the need to improve accessibility to these services. Moreover, the results underscore the importance of thoughtful deliberation regarding the application of EoL medical interventions in cancer patients.

O 09 - Radiotherapy utilization and outcomes from a contemporary study of brentuximab vedotin with chemotherapy in pediatric high-risk Hodgkin lymphoma

O 09 - Radiotherapy utilization and outcomes from a contemporary study of brentuximab vedotin with chemotherapy in pediatric high-risk Hodgkin lymphoma