Course Of Radiotherapy Research Articles

Stereotactic Body Radiation Therapy: A Radiosurgery Society Guide to the Treatment of Localized Prostate Cancer Illustrated by Challenging Cases

Traditionally, external beam radiotherapy (EBRT) for localized prostate cancer (PCa) involved lengthy courses with low daily doses. However, advancements in radiation delivery and a better understanding of prostate radiobiology have enabled the development of shorter courses of EBRT. Ultrahypofractionated radiotherapy, administering doses greater than 5 Gy per fraction, is now considered a standard of care regimen for localized PCa, particularly for intermediate-risk disease. Stereotactic body radiotherapy (SBRT), a specific type of ultrahypofractionated radiotherapy employing advanced planning, imaging, and treatment technology to deliver in five or fewer fractions, is gaining prominence as a cost-effective, convenient, and safe alternative to longer radiotherapy courses. It is crucial to address practical considerations related to patient selection, fractionation scheme, target delineation, and planning objectives. This is especially important in challenging clinical situations where clear evidence for guidance may be lacking. The Radiosurgery Society endorses this case-based guide with the aim of providing a practical framework for delivering SBRT to the intact prostate, exemplified by two case studies. The article will explore common SBRT dose/fractionation schemes and dose constraints for organs-at-risk. Additionally, it will review existing evidence and expert opinions on topics such as SBRT dose escalation, the use of rectal spacers, the role of androgen deprivation therapy in the context of SBRT, SBRT in special patient populations (e.g., high-risk disease, large prostate, high baseline urinary symptom burdens, and inflammatory bowel disease), as well as new imaging-guidance techniques like Magnetic Resonance Imaging for SBRT delivery.

Effect of ionizing radiation (radiation therapy) on the structural and functional state of serum albumin with cervical cancer

The study of the literature on the detoxification properties of an albumin molecule and a prognostic value of determining albumin indicators allows us to conclude that it is undoubtedly important to assess the structural and functional properties of albumin in cancer patients at all stages of the diagnostic and treatment process already at the present time. At the same time, the lack of information makes it necessary and promising to widely introduce the fluorescent method for assessing total and effective albumin concentrations in the clinical and scientific work of oncologists.Therefore, the aim of our work was to study the effect of radiation therapy on the structural and functional state of serum albumin in patients with cervical cancer.In order to study radiation-induced changes in serum albumin when irradiated with therapeutic doses of ionizing radiation, the biological material (blood) of 28 people from the Gomel region was used: 1st group (control) – 13 healthy people; 2nd group – 15 patients diagnosed with cervical cancer who underwent remote gamma therapy (30 Gy). The collection of biological material in the 2nd group was carried out as follows: upon admission to patient treatment; after the 1st session of radiotherapy (2 Gy); after the 3rd session of radiotherapy (6 Gy); after the 5th session of radiotherapy (10 Gy); after the 7th session of radiotherapy (14 Gy); after the 10th session of radiotherapy (20 Gy), and after the 15th session of radiotherapy (30 Gy).According to A. Gryzunov, G. E. Dobretsov’s method, the following indicators were determined: total albumin concentration (TAC) − the number of albumin molecules capable of binding toxic ligands is equal to the albumin concentration determined in any other way; effective albumin concentration (EAC) − the number of albumin binding centers is unoccupied by toxic ligands; the reserve of albumin binding (RAB) − it reflects the degree of structural modification of the protein; the index of toxicity (IT) − it characterizes the filling of albumin centers with toxic ligands.The total albumin concentration is within normal values, both for healthy and cancer patients throughout the course of radiation therapy. The analysis of the indicators characterizing the structural and functional state of serum albumin (EAC, RAB, and IT) in patients with cervical cancer showed that the amount of fully functioning protein statistically significantly decreases when compared with a group of healthy people.When studying the effect of radiation therapy on the structural and functional state of serum albumin in cancer patients, the following was determined: in 57 % of cases, the values of the IT indicator increase after a course of radiotherapy, and in 43 % − decrease;after the 1st session of radiotherapy, further dynamics of IT after treatment is determined: if after 2 Gy the values of the IT indicator increase, then by the end of therapy this indicator will be higher than that when entering treatment, and, conversely, if after 2 Gy the values of the IT indicator decrease, then after the course of radiotherapy this indicator will be less than that when entering treatment;it is possible that the patient’s place of residence is a determining factor in the development of an individual reaction of the serum albumin transport system to the effect of therapeutic doses of ionizing radiation.The determination of albumin indicators characterizing the structural and functional state of serum albumin, in particular, the index of toxicity in patients with cervical cancer should be used as an individual diagnostic and prognostic criterion in the dynamics of observation of patients undergoing radiation therapy.

Outcomes of Isocitrate Dehydrogenase Wild Type Glioblastoma after Re-irradiation.

Glioblastomas (GBM) are the most common malignant primary brain tumors in adults and have a dismal prognosis. Patients frequently suffer from local tumor recurrences, with limited therapeutic options. Re-irradiation represents a possible intervention, but given the recent 5th edition of the World Health Organization classification of central nervous system tumors, studies in isocitrate dehydrogenase wild type (IDH-wt) cohorts undergoing a second course of radiotherapy remain limited. Herein, we sought to describe our institutional experience and outcomes after GBM IDH-wt re-irradiation. GBM patients with confirmed IDH-wt status undergoing re-irradiation were included in this single-center, retrospective analysis. A total of 88 patients were analyzed. The median clinical and radiographic follow-up periods were 4.6months and 4.4months, respectively. Most patients had a Karnofsky performance status of at least 80% (n=57). The median biologically effective dose and 2Gy equivalent dose (EQD2) for re-irradiations, assuming an α/β ratio of 10Gy for GBM, were 51.4 and 42.8Gy, respectively. In total, 71 deaths were recorded. The median overall survival (OS) was 8.0months. Multivariable Cox regression of OS revealed a positive influence of gross total resection vs. biopsy or no resection (hazard ratio: 0.43, p=0.02). The median progression-free survival (PFS) was 5.9months. The multivariable Cox regression for PFS did not detect any significant factors. No clear evidence of radiation necrosis was recorded during the available follow-up. However, only a minority (n=4) of patients underwent surgery after re-irradiation, none showing histopathological proof of radiation necrosis. The prognosis for recurrent IDH-wt GBM after re-irradiation is poor. Patients who are amenable and able to undergo re-resection may have a favorable OS. A second course of radiotherapy with a moderate cumulative EQD2 and small- to medium-sized planning target volumes appeared safe regarding the occurrence of radiation necrosis.

A Prospective Study Demonstrating Early Prediction of Skin Toxicity From Radiation Therapy Using Radiomic Features From Optical and Infrared Images

Approximately 90% of patients undergoing breast cancer radiation therapyexperience skin toxicities that are difficult to classify and predict ahead of time. A prediction oftoxicityat the early stages of the treatment would provide clinicians with a prompt to intervene. The objectives of this study were to evaluate the correlation between skin toxicity and radiomic features extracted from optical and infrared (thermal) images of skin, and to develop a model for predicting a patient's skin response to radiation. Optical and infrared breast and chest-wall images were acquired daily during the course of radiation therapy, as well as weekly for 3 weeks after the end of treatment for 20 patients with breast cancer. Skin-toxicity assessments were conducted weekly until the patients' finalvisit. Skin color and temperature trends from histogram-based and texture-based radiomic features, extracted from the treatment area, were analyzed, reduced, and used in a cross-validation machine learning model to predict the patients' skin toxicity grades. A set of 9 independent color and temperature features with significant correlation to skin toxicitywere identified from 108 features. The cross-validation accuracy of a cubic Support Vector Machine remained >85% and area under the receiver operating characteristic curve remained>0.75,when reducing the input imaging data to include onlythe sessions with a biologically effective dosenot exceeding30 Gy(approximately the first third to first half of the total treatment dose). The quantitative analysis of radiomic featuresextracted from opticaland infrared (thermal) images of skinwas shown to be promising for predicting skin toxicities.

Distress Scores During Radiotherapy for Lung Cancer: Course and Prognostic Factors.

Cancer treatment can lead to significant distress. We investigated the course of distress during radiotherapy (RT) for lung cancer. Data of 159 patients receiving RT for lung cancer were investigated for change of distress scores during RT. Five characteristics were analyzed including age, sex, Karnofsky performance score, intent of RT, and receipt of previous RT. Additional analyses were performed in patients with pre-RT scores ≤5 points. Mean pre-RT and post-RT distress scores were 5.5 (±2.6) and 4.7 (±2.6), respectively. No characteristic was significantly associated with mean change or increase of distress. In patients with pre-RT scores ≤5 points, non-significantly higher rates of increased distress were found for age ≤64 years, female sex, and Karnofsky performance score 90-100. Distress is reduced during a course of RT for lung cancer. This may reflect a reduction in anticipatory distress after first-hand experience.

Influence of interruptions in radiation therapy on long-term results of treatment of stage I-III head and neck cancers in the absence of surgical and chemoradiotherapy

Despite the fact that head and neck tumors are very sensitive to radiation treatment, patients who have completed a course of radiation therapy have a high rate of recurrence and mortality from the underlying disease.The aim of the study was to analyze the event-free survival of patients who completed a course of radiation therapy for stage I-III head and neck cancer according to a radical program under the influence of a number of independent factors such as age, gender, total focal dose, disease stage, duration of a break in a split course of radiation therapy.The effect of the duration of interruption on survival was assessed by analyzing the treatment regimens for patients who received radiation treatment for stage I-III head and neck cancer according to a radical program from 2016 to 2018 at the Brest Regional Oncological Dispensary. Statistical processing of the obtained data included the analysis by the Cox regression method. Data were analyzed using the Kaplan-Meier method to evaluate the outcome.In the multivariate analysis, it was found that the disease stage has the greatest relationship with event-free survival (p < 0.01). The same trend is observed for the duration of interruption in radiotherapy (p < 0.05). The cumulative survival was significantly higher in the group of patients with treatment interruption of less than 3 weeks compared to the group of patients who completed treatment more than 3 weeks apart (80.00 % vs 49.06 %). If the duration of the break is less than 3 weeks, the clinical stage (T1-T3) is not a factor influencing patient survival.Accounting for the effect of interruptions in the course of radiotherapy and the understanding the influence of controllable factors is essential for optimal treatment strategies.

Endoscopically placed fiducial markers for image-guided radiotherapy in preoperative gastric cancer: Technical feasibility and potential benefit.

Background and study aims Fiducial markers have demonstrated clinical value in radiotherapy in several organs, but little is known about markers in the stomach. Here, we assess the technical feasibility of endoscopic placement of markers in gastric cancer patients and their potential benefit for image-guided radiotherapy (IGRT). Patients and methods In this prospective feasibility study, 14 gastric cancer patients underwent endoscopy-guided gold (all patients) and liquid (7 patients) marker placements distributed throughout the stomach. Technical feasibility, procedure duration, and potential complications were evaluated. Assessed benefit for IGRT comprised marker visibility on acquired imaging (3-4 computed tomography [CT] scans and 19-25 cone-beam CTs [CBCTs] per patient) and lack of migration. Marker visibility was compared per marker type and location (gastroesophageal junction (i.e., junction/cardia), corpus (corpus/antrum/fundus), and pylorus). Results Of the 93 marker implantation attempts, 59 were successful, i.e., marker in stomach wall and present during entire 5-week radiotherapy course (2-6 successfully placed markers per patient), with no significant difference (Fisher's exact test; P >0.05) in success rate between gold (39/66=59%) and liquid (20/27=74%). Average procedure duration was 24.4 min (range 16-38). No procedure-related complications were reported. All successfully placed markers were visible on all CTs, with 81% visible on ≥95% of CBCTs. Five markers were poorly visible (on <75% of CBCTs), possibly due to small marker volume and peristaltic motion since all five were liquid markers located in the corpus. No migration was observed. Conclusions Endoscopic placement of fiducial markers in the stomach is technically feasible and safe. Being well visible and positionally stable, markers provide a potential benefit for IGRT.

Development of Distress During a Radiotherapy Course for Head-and-neck Cancer.

Radiotherapy (RT) is a standard treatment for head-and-neck cancer, which can be associated with patient distress. This study provides data investigating distress during head-and-neck RT. Fifty-six patients completed the Distress Thermometer before and on the last day of their RT-course. Mean changes of distress scores and increase of distress were evaluated. Age, sex, Karnofsky performance score (KPS), tumor type, intent of RT, and previous RT were analyzed for associations with course of distress. Mean pre-RT and post-RT distress scores were 5.1 (±2.6) and 5.0 (±2.7) points, respectively (mean change: ±0.0 points). Mean change of distress scores was significantly associated with age (p=0.042) and KPS (p<0.001). On multivariable analysis, increased distress (by ≥2 points) was associated with KPS 90-100 (p=0.011) and palliative intent of RT (p=0.036). Mean pre-RT and post-RT distress scores were almost identical. Patients with risk factors for increased distress during their RT-course should be offered immediate psychological support.

Stereotactic Body Radiation Therapy for Spine Metastases-Findings from an Australian Population-Based Study.

Background: To evaluate the use of stereotactic body radiation therapy (SBRT) for spine metastases and the associated factors in Australia. Methods: The Victorian Radiotherapy Minimum Dataset, which captures all episodes of radiotherapy delivered in the state of Victoria, was accessed to evaluate the patterns and trends of SBRT for spine metastases. The primary outcome was SBRT use and associated factors. Results: There were 6244 patients who received 8861 courses of radiotherapy for spine metastases between 2012 and 2017. Of these, 277 (3%) courses were SBRT, which increased from 0.4% in 2012 to 5% in 2017 (P-trend < 0.001). There was a higher proportion of SBRT use in patients with prostate cancer (6%) and melanoma (4%) compared to other cancers (2-3%) (p < 0.001). Patients from the highest socioeconomic quintiles (5%) were more likely to be treated with SBRT compared to patients from the lowest socioeconomic quintiles (3%) (p < 0.001). There was a higher proportion of SBRT use in private radiotherapy centres (6%) compared to public radiotherapy centres (1%) (p < 0.001). No spine SBRT was delivered in regional centres. In multivariate analyses, the year of treatment, age, primary cancers and radiotherapy centres were independently associated with SBRT use. Conclusion: This is the first Australian population-based study quantifying the increasing use of spine SBRT; however, the overall use of spine SBRT remains low. We anticipate an ongoing increase in spine SBRT, as spine SBRT gradually becomes the standard-of-care treatment for painful spine metastases.

Impact of multidisciplinary team on the pattern of care for brain metastasis from breast cancer.

The aim of this study was to explore how a multidisciplinary team (MDT) affects patterns of local or systematic treatment. We retrospectively reviewed the data of consecutive patients in the breast cancer with brain metastases (BCBM) database at our institution from January 2011 to April 2021. The patients were divided into an MDT group and a non-MDT group. A total of 208 patients were analyzed, including 104 each in the MDT and non-MDT groups. After MDT, 56 patients (53.8%) were found to have intracranial "diagnosis upgrade". In the matched population, patients in the MDT group recorded a higher proportion of meningeal metastases (14.4% vs. 4.8%, p = 0.02), symptomatic tumor progression (11.5% vs. 5.8%, p = 0.04), and an increased number of occurrences of brain metastases (BM) progression (p < 0.05). Attending MDT was an independent factor associated with ≥2 courses of intracranial radiotherapy (RT) [odds ratio (OR) 5.4, 95% confidence interval (CI): 2.7-10.9, p < 0.001], novel RT technique use (7.0, 95% CI 3.5-14.0, p < 0.001), and prospective clinical research (OR 5.7, 95% CI 2.4-13.4, p < 0.001). Patients with complex conditions are often referred for MDT discussions. An MDT may improve the qualities of intracranial RT and systemic therapy, resulting in benefits of overall survival for BC patients after BM. This encourages the idea that treatment recommendations for patients with BMBC should be discussed within an MDT.

Efficacy of Plantago major leaf extract cream compared to placebo in preventing acute radiodermatitis in breast cancer patients: A randomized clinical trial

IntroductionDermatitis is a common side effect of radiotherapy (RT). Plantago major L. leaves (P. major) exhibit anti-inflammatory and wound-healing activities. This study aimed to evaluate the preventive effect of P. major on acute radiodermatitis in breast cancer patients. MethodsThis randomized controlled trial involved 78 breast cancer patients who had undergone modified radical mastectomy and were scheduled for RT. After random allocation, the control group (n = 39) received a placebo and the intervention (n = 39) group received P. major cream. It was used as an external application twice per day from the first day of RT until two weeks after the completion of the radiation course. The patients were examined weekly by a physician. The primary outcome was the incidence and severity of acute radiodermatitis, graded according to Radiation Therapy Oncology Group and the European Organization for Research and Treatment of Cancer (RTOG/EORTC) and National Center Institute Common Terminology Criteria for Adverse Events, version 5 (NCI-CTCAE) toxicity scoring systems. ResultsRadiodermatitis grades ≥2 according to the RTOG/EORTC and NCI-CTCAE scoring systems developed from the third week of RT, peaking in the sixth week in both groups. The incidence of grades ≥2 acute dermatitis was lower in patients treated with topical P. major than with the placebo (51.3% vs. 66.7%), but this difference was not statistically significant (relative risk = 0.769, 95% confidence interval, 0.429–1.373). Dermatitis grades ≥2 had no relationship with body mass index ≥30 and older age. Itching during the six weeks of follow-up was more common in the P. major group. ConclusionThis study revealed that 7% P. major cream did not significantly decrease the severity of acute radiodermatitis. Conducting multicenter trials with larger sample sizes and using different topical agents based on P. major are recommended for future studies. Trial registrationIRCT20150830023823N4.

Serum-based parameters as distinctive predictive biomarkers in patients with hepatocellular carcinoma undergoing curative radiation therapy.

48 Background: The aim of this study was to investigate whether serum immune and inflammatory parameters can help to predict the clinical outcomes in patients with unresectable hepatocellular carcinoma (HCC) undergoing curative radiation therapy (RT). Methods: A total of 76 RT courses among 71 patients between January 2014 and April 2019 were analyzed. The following variables were included in the analysis: systemic inflammation index, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio (PLR), prognostic nutritional index (PNI), absolute lymphocyte count, lymphocyte-to-monocyte ratio (LMR), albumin, albumin-to-alkaline phosphatase ratio, RT-related parameters, and levels of total protein, hemoglobin, α- fetoprotein, PIVKA-II, and C-reactive protein. Overall survival (OS), local control (LC), distant control (DC), and intrahepatic control (IHC) rates were calculated using the Kaplan-Meier method, and graphs were compared using the log-rank test. The multivariate Cox model was used to identify independent prognostic factors. The optimal cutoff values for survival separation were decided using the maximal chi-square test. Results: The mean age was 61.4 years, and most patients were men (n = 62, 81.6%). Most of the study population underwent pre-RT TACE/HAIC (n = 74, 97.4%). The median RT fraction number, fractional doses, and biologically equivalent doses by α/β=10 were 12 (range, 4–30), 5 (range, 2–12) Gy and 72.6 (range, 51.5–119) Gy, respectively. With a median follow-up of 12 (range, 3.1–56.7) months, the 1-year OS, LC, DC, and IHC rates were 55.2%, 88.2%, 64.4%, and 50.5%, respectively. In the multivariate analysis, significant independent prognostic indicators were the lowest posttreatment PNI for OS ( P &lt; 0.001), lowest pretreatment LMR for LC ( P = 0.03), and highest posttreatment PLR for DC ( P = 0.006). Conclusions: Distinct serum-based parameters predicted OS, LC, and DC rates. Future research is necessary to confirm our findings.

Towards estimating the carbon footprint of external beam radiotherapy

PurposeThe National Health Service (NHS) in the United Kingdom (UK) is aiming to be carbon net zero by 2040 to help limit the dangerous effects of climate change. Radiotherapy contributes to this with potential sources quantified here. MethodActivity data for 42 patients from within the breast IMRT and prostate VMAT pathways were collected. Data for 20 prostate patients was also collected from 3 other centres to enable cross centre comparison. A process-based, bottom-up approach was used to calculate the carbon footprint. Additionally, patients were split into pre-COVID and COVID groups to assess the impact of protocol changes due to the pandemic. ResultsThe calculated carbon footprint for prostate and breast pre-COVID were 148 kgCO2e and 101 kgCO2e respectively, and 226 kgCO2e and 75 kgCO2e respectively during COVID. The energy usage by the linac during treatment for a total course of radiotherapy for prostate treatments was 2–3 kWh and about 1 kWh for breast treatments. Patient travel made up the largest proportion (70–80%) of the calculated carbon footprint, with linac idle power second with ∼ 10% and PPE and SF6 leakage were both between 2 and 4%. ConclusionThese initial findings highlight that the biggest contributor to the external beam radiotherapy carbon footprint was patient travel, which may motivate increased used of hypofractionation. Many assumptions and boundaries have been set on the data gathered, which limit the wider application of these results. However, they provide a useful foundation for future more comprehensive life cycle assessments.

Radiotherapy resources in Brazil (RT2030): a comprehensive analysis and projections for 2030

The demand for radiotherapy in Brazil is unfulfilled, and the scarcity of data on the national network hampers the development of effective policies. We aimed to evaluate the current situation, estimate demands and requirements, and provide an action plan to ensure access to radiotherapy for those in need by 2030. The Brazilian Society for Radiation Oncology created a task force (RT2030) including physicians, medical physicists, policy makers, patient advocates, and suppliers, all of whom were major stakeholders involved in Brazilian radiotherapy care. The group was further divided into seven working groups to address themes associated with radiotherapy care in Brazil. From March 1, 2019, to Aug 3, 2020, there were monthly meetings between the group's leaders and the Central Committee and six general meetings. First, a comprehensive search of all different national databases was done to identify all radiotherapy centres. Questionnaires evaluating radiotherapy infrastructure and human resources and assing the availability, distribution, capacity, and workload of resources were created and sent to the radioprotection supervisor of each centre. Results were analysed nationally and across the country's regions and health-care systems. A pre-planned review of available databases was done to gather data on active radiation oncology centres and the distribution of radiotherapy machines (linear accelerators [LINACs]) across Brazil. We used national population and cancer incidence projections, recommended radiotherapy usage from the medical literature, and national working patterns to project radiotherapy demands in 2030. An action plan was established with suggestions to address the gaps and meet the demands. The database search yielded 279 centres with an active radiotherapy registry. After applying predefined exclusion criteria, 263 centres were identified that provided external beam radiotherapy machines with or without brachytherapy. All 263 operational centres answered the questionnaires sent on Dec 9, 2019, which were then returned between Jan 1 and June 30, 2020. There were 409 therapy machines, 646 radiation oncologists, 533 physicists, and 230 989 patients undergoing radiotherapy (150 628 [65·2%] in the public health-care system and 80 937 [35·0%] in private). The mean annual occupation rate was 566 patients per treatment machine (SD 250). The number of residents per treatment machine ranged from 258 333 to 1 800 000. Technology availability varied considerably among regions and systems. In 2030, 639 994 new cancer cases are expected, which will require 332 797 radiotherapy courses. Therefore, 530 LINACs, 1079 radiation oncologists, and 1060 medical physicists will be needed. The expected increase in cancer incidence in the coming years will probably increase the disparities in cancer care and the burden for Brazilian patients. We provide a roadmap of the current situation and the particularities of the Brazilian radiotherapy network, which can serve as a starting point for cancer policy planning to improve this scenario. Accuray, BRAINLAB, Elekta, IBA, ONE medical solution, SUN NUCLEAR corporation, VARIAN, and ZIGMA.

Post-radiotherapy osteomyelitis of the cervical spine in head and neck cancer patients

Objective To evaluate patient characteristics, risk factors, disease course, and management of cervical vertebral osteomyelitis in patients who had radiation for head and neck cancers. Methods A retrospective cohort study (case series) of patients diagnosed with post-radiation osteomyelitis of the cervical spine between 2012 and 2021. Data were collected from the patient’s medical files. Results Seven patients (71% male) with post-radiation cervical osteomyelitis were reviewed. The median patient age was 64 years. The mean interval between diagnosis of osteomyelitis and the first and last radiotherapy course was 8.3 and 4.0 years, respectively. A medical or surgical event preceded the diagnosis in four patients (57%) by a mean of 46.25 days. Common imaging findings were free air within the cervical structures and fluid collection. Four patients recovered from osteomyelitis during the follow-up within an average of 65 days. Conclusion: Post-radiation osteomyelitis is characterized by a subtle presentation, challenging diagnosis, prolonged treatment, and poor outcome. Clinicians should maintain a high index of suspicion for the long-term after radiotherapy. Multidisciplinary evaluation and management are warranted. Advances in knowledge: The study describes post-radiotherapy osteomyelitis of the cervical spine, a rare and devastating complication. Literature data regarding this complication are sparse.

Proton Beam Therapy in the Reirradiation Setting of Brain and Base of Skull Tumour Recurrences

The therapeutic management of local tumour recurrence after a first course of radical radiotherapy is always complex. Surgery and reirradiation carry increased morbidity due to radiation-induced tissue changes. Proton beam therapy (PBT) might be advantageous in the reirradiation setting, thanks to its distinct physical characteristics. Here we systematically reviewed the use of PBT in the management of recurrent central nervous system (CNS) and base of skull (BoS) tumours, as published in the literature. The research question was framed following the Population, Intervention, Comparison and Outcomes (PICO) criteria: the population of the study was cancer patients with local disease recurrence in the CNS or BoS; the intervention was radiation treatment with PBT; the outcomes of the study focused on the clinical outcomes of PBT in the reirradiation setting of local tumour recurrences of the CNS or BoS. The identification stage resulted in 222 records in Embase and 79 in Medline as of March 2023. Sixty-eight duplicates were excluded at this stage and 56 were excluded after screening as not relevant, not in English or not full-text articles. Twelve full-text articles were included in the review and are presented according to the site of disease, namely BoS, brain or both brain and BoS. This review showed that reirradiation of brain/BoS tumour recurrences with PBT can provide good local control with acceptable toxicity rates. However, reirradiation of tumour recurrences in the CNS or BoS setting needs to consider several factors that can increase the risk of toxicities. Therefore, patient selection is crucial. Randomised evidence is needed to select the best radiation modality in this group of patients.

Experience with intraoperative radiation therapy in an urban cancer center

Background/objectiveIntra-operative radiation therapy (IORT) is a newer partial breast irradiation technique that has been well studied in 2 large randomized trials, the TARGIT-A and ELIOT trials. We initiated our IORT program in 2018 in the context of a registry trial, and aim to report our early results thus far.MethodsWe instituted an IORT practice using Intrabeam® low energy 50kVp x-rays for selected breast cancer cases in 2018. Patients were enrolled on our institutional registry protocol which allowed for IORT in ER + patients with grade 1–2 DCIS ≤ 2.5 cm or invasive disease ≤ 3.5 cm in patients of at least 45 years of age.ResultsBetween January 2018 and December 2021, 181 patients with clinical stage 0-IIA ER + breast cancer were evaluated. One hundred sixty-seven patients ultimately received IORT to 172 sites. The majority of patients received IORT at the time of initial diagnosis and surgery (160/167; 95.8%). Re-excision post IORT occurred in 16/167 patients (9.6%) due to positive margins. Adjuvant RT to the whole breast +/- LN was ultimately given to 23/167 (13.8%) patients mainly due to positive sentinel LN found on final pathology (12/23; 52%); other reasons were close margins for DCIS (3/23; 13%), tumor size (3/23; 4.3%), and multifactorial (5/23; 17.4%). Five patients (3%) had post-operative complications of wound dehiscence. There were 3 local recurrences (1.6%) at a median follow-up of 27.9 months (range: 0.7– 54.8 months).ConclusionsIORT has been proven to be a safe and patient-centered form of local adjuvant RT for our population, in whom compliance with a longer course of external beam radiation can be an issue. Long term efficacy remains to be evaluated through continued follow up. In the era of COVID-19 and beyond, IORT has been an increasingly attractive option, as it greatly minimizes toxicities and patient visits to the clinic.Trial registrationAll patients were prospectively enrolled on an institutional review board-approved registry trial (IRB number: 2018–9409).

Radiation Skin Injury Care in Radiotherapy for Oncology: Mechanisms, Drug Therapy and Novel Biomaterial Application Strategies

AbstractRadiation skin injury (RSI) is a frequent adverse effect of radiation therapy for malignant tumors. It often leads to problems such as decreased quality of life in patients and interferes with the normal course of radiation therapy (RT). With the rising incidence of tumors and the burgeoning number of patients undergoing RT, the care of RSI is of crucial importance in cancer patient treatment. Currently, drugs and biomaterials are widely used in the care of RSI. However, there is no international consensus on the current protocol for the therapeutic care of RSI. Many drugs and biomaterials cannot be applied to the appropriate type of radiation dermatitis, resulting in unfavorable results in the therapeutic care of RSI. The choice of appropriate drugs and biomaterials for the therapeutic care of the different types of RSI is essential to improving the quality of life of patients. This article first reviews the main mechanisms of acute and chronic RSI. Subsequently, the application of drugs and novel biomaterials in the preventive, acute, and chronic phases of the care of RSI is summarized. Finally, the suggestions and protocols for the application of novel biomaterials in the care of RSI are discussed, as are the current challenges and future prospects for the development of combined biomaterials and integrated care solutions.

Serial Changes in Parotid Gland Volume and Symptoms After Radiation Therapy in Oropharyngeal Cancer.

Objective: To evaluate the serial changes in the volume of the parotid gland and clinical symptoms after a course of radiation therapy (RT) in patients with oropharyngeal cancer. Methods: A total of 33 patients who were diagnosed with oropharyngeal cancer and had been treated with RT or concurrent chemoradiation therapy were evaluated. Parotid gland volumes were measured serially by head and neck computed tomography with contrast-enhanced images before RT, and 6 months, 1 year, and 2 years after RT. Patients also filled out EORTC (European Organization for the Research and Treatment of Cancer) QLQ-C30 questionnaires on the quality of life (QOL) at the same time. This questionnaire included questions about salivary gland function: dry mouth, sticky saliva, and taste disorder. Higher scores on EORTC questionnaire translates to worse QOL. Results: All patients received more than 60 Gy irradiation in total. The mean volume of parotid gland decreased from 23.30 mL before RT to 15.80 mL, 15.93 mL, and 16.67 mL after 6 months, 1 year, and 2 years, respectively (P < 0.001 between pre-RT and all other 3 periods). The scores on the QOL questionnaire were higher (worsened QOL) at all 3 times after radiation than in the pre-RT period. The mean score of QOL increased from pre-RT to 2 years post-RT: "dry mouth" from 1.65 to 2.70, "sticky saliva" from 1.19 to 2.00, and "taste disorder" from 1.12 to 1.94. All 3 of these parameters were correlated with the volume of the parotid gland (P < 0.005 each). Conclusions: The volume of the parotid gland decreases significantly after RT for oropharyngeal cancer and does not recover significantly for at least 2 years. There was a significant correlation between decreased parotid volume and a lower QOL involving salivation.

30 GY IN 4 STEREOTACTIC BODY RADIOTHERAPY (SBRT) FRACTIONS FOR COMPLEX SPINAL METASTASES: MATURE OUTCOMES SUPPORTING THIS NOVEL REGIMEN

Abstract We designed a 30 Gy in 4 fractions stereotactic body radiotherapy (SBRT) protocol, as an alternative option to our standard 2-fraction approach, for primarily large volume, multilevel, or previously radiated spinal metastases. We report imaging-based outcomes of this novel fractionation scheme. MATERIALS AND METHODS: Retrospective analysis of all patients who underwent 30 Gy/4 fractions from 2010-2021 identified from an institutional database. Primary outcomes were magnetic resonance-based vertebral compression fracture (VCF) and local failure (LF). RESULTS: We reviewed 245 treated segments in 116 patients. The median number of consecutive segments within the treatment volume was 2 (range, 1-6) and clinical target volume (CTV) was 126.2 cc (range, 10.4-863.5). Fifty-four percent had received at least one prior course of radiotherapy. The cumulative incidence of LF was 10.7% (95% CI 7.1-15.2) at 1 year and 16% (95% CI 11.5-21.2) at 2 years. The cumulative incidence of VCF was 7.3% (95% CI 4.4-11.2) at 1 and 11.2% (95% CI 7.5-15.8) at 2 years. On multivariable analysis, age ≥68 years (p=0.038), CTV volume ≥72 cc (p=0.021), and no prior surgery (p=0.021) predicted for VCF. The risk of VCF for CTV volumes &amp;lt;72 cc/≥72 cc was 1.8%/14.6% at 2 years. No case of radiation-induced myelopathy was observed. CONCLUSION: 30 Gy in 4 fractions was safe and efficacious despite a population at increased risk of toxicity. The lower risk of VCF in previously stabilized segments highlights the potential for a multi-modal treatment approach for complex metastases, especially for those with CTV volume ≥72 cc.