Palliative Radiotherapy in Non-small Cell Lung Cancer: Patterns of Use and Predictors of 30-Day Mortality in End-of-Life Care.

Introduction Lung cancer is the leading cause of cancer-related deaths worldwide, with non-small cell lung cancer (NSCLC) being the most common type. More than half of patients require radiotherapy throughout their treatment. Palliative radiotherapy (PRT) is an important tool for symptom control and quality of life improvement in advanced NSCLC patients. However, the benefits of PRT must be balanced against possible disadvantages, especially in end-of-life (EOL) care. This study aims to describe the profile of PRT-treated deceased NSCLC patients, quantify the proportion of PRT recipients in the last 30 days of life and identify short-term survival prognostic factors in this group. Materials and methods This retrospective analysis was performed at two radiotherapy facilities within the Kent Oncology Centre, UK, for two years, running from January 1, 2022, to January 1, 2024. Data were collected from 857 deceased NSCLC patients who received PRT. Demographics, cancer diagnosis, histology, tumour, node, metastasis (TNM) staging, radiotherapy details, recent treatments, performance status (PS) and comorbidities were analysed. Patients have been stratified as long-term survivors (more than 30 days after PRT initiation, LTS group) along with short-term survivors (STS) (died within 30 days, STS group). Descriptive statistics, chi-squared tests, t-tests and multivariable logistic regression have been used in the data analysis. Results Out of 857 patients, 148 (17.3%) died within 30 days of PRT initiation. PS was considerably worse (p = 0.027), Adult Comorbidity Evaluation 27 (ACE-27) scores were higher (p = 0.018), and metastatic disease was more prevalent (60.1% vs. 47.5%, p = 0.02) in STS group patients. Fewer patients in the STS group completed their treatment compared to the LTS group (63.5% vs. 82.8%, p < 0.001). The STS group also received lower mean radiation dose (17.7 Gy vs. 19.6 Gy, p = 0.022) and fewer fractions (4.4 vs. 5.2, p = 0.019). The most common RT regimen in both cohorts was 20 Gy in five fractions, used in 55.4% of STS and 49.8% of LTS patients, with no significant difference in single fraction RT use between groups (33.1% in STS vs. 36.8% in LTS, p = 0.401). Multivariate logistic regression identified significant predictors of 30-day mortality: poorer PS (adjusted OR: 1.981, 95% CI: 1.33-3.12, p = 0.001), metastatic disease (adjusted OR: 2.02, 95% CI: 1.246-3.571, p = 0.002), incomplete PRT (adjusted OR: 0.337, 95% CI: 0.21-0.514, p < 0.001) and no recent chemotherapy (adjusted OR: 0.542, 95% CI: 0.342-0.941, p = 0.044). Conclusion This study demonstrated that compared with previous reports, a higher proportion of NSCLC patients who received PRT died within 30 days of treatment initiation, and low treatment adherence rates highlight challenges in EOL settings. Identification of poor PS and metastatic disease as predictors of short-term mortality would help inform PRT decision-making. The underutilisation of single-fraction radiotherapy and the link between recent chemotherapy and lower 30-day mortality warrant further study. These results highlight the need for better prognostic tools and more selective use of PRT, including increased consideration of single-fraction radiotherapy, in NSCLC patients approaching end of life and emphasise the importance of balancing benefit against treatment burden in this vulnerable population.

Comparative efficacy of palliative radiotherapy dose schedules in advanced bladder cancer-associated gross hematuria.

Introduction: Gross hematuria (GH) in advanced/inoperable bladder cancer patients causes significant morbidity. Patients frequently need multiple transfusions. Hypofractionated radiotherapy (RT) has been shown to be effective in symptom palliation. In this study, we explore the efficacy of various fractionation regimens in these patients. Methods: This single institute retrospective analysis was conducted on 60 consecutive patients treated with palliative RT. Fractionation (single versus multiple) and biologically equivalent doses (BED; high ≥36 Gy versus low <36 Gy) were used to compare the efficacy of various fractionation regimens. The primary outcome was the difference in objective response rate (ORR) between various strata at 2, 4, 8 and 12 weeks. Major secondary outcomes were differences in ORR according to Eastern Cooperative Oncology Group (ECOG) performance status (PS) and tumour node metastases (TNM) stage, and the proportion of patients requiring re-transfusion(s) at 12 weeks. Data were analysed using SPSS 23. Results: Overall ORR at 2, 4, 8 and 12 weeks was 86%, 77%, 67% and 55%, respectively. There was no statistically significant difference in response rates between single or multi-fraction, or high versus low BED groups (All p = >0.05). Moreover, ECOG PS (p = 0.11) or TNM stage (p = 0.58) also had no impact on the response rate at 12 weeks. Nearly one-third (31%) of patients required further transfusions at 12 weeks. Conclusion: RT is an effective modality to control GH. No difference in ORR was found between single fractions versus multiple fractions, or high versus low BED regimens. Single fraction RT can be offered to these patients considering low cost, patient convenience and minimal side effects.

Determinants of cerebral radionecrosis in animal models: A systematic review.

BACKGROUND: Radionecrosis is a common complication in radiation oncology, while mechanisms and risk factors have yet to be fully explored. We therefore conducted a systematic review to understand the pathogenesis and identify factors that significantly affect the development. METHODS: We performed a systematic literature search based on the PRISMA guidelines using PubMed, Ovid, and Web of Science databases. The complete search strategy can be found as a preregistered protocol on PROSPERO (CRD42023361662). RESULTS: We included 83 studies, most involving healthy animals (n = 72, 86.75 %). High doses of hemispherical irradiation of 30 Gy in rats and 50 Gy in mice led repeatedly to radionecrosis among different studies and set-ups. Higher dose and larger irradiated volume were associated with earlier onset. Fractionated schedules showed limited effectiveness in the prevention of radionecrosis. Distinct anatomical brain structures respond to irradiation in various ways. White matter appears to be more vulnerable than gray matter. Younger age, more evolved animal species, and genetic background were also significant factors, whereas sex was irrelevant. Only 13.25 % of the studies were performed on primary brain tumor bearing animals, no studies on brain metastases are currently available. CONCLUSION: This systematic review identified various factors that significantly affect the induction of radionecrosis. The current state of research neglects the utilization of animal models of brain tumors, even though patients with brain malignancies constitute the largest group receiving brain irradiation. This latter aspect should be primarily addressed when developing an experimental radionecrosis model for translational implementation.

Self-Shielding Gyroscopic Radiosurgery for Uveal Melanoma: A First Case Report.

Stereotactic radiosurgery (SRS) is a well-established treatment modality for the management of uveal melanoma, achieving high tumor control and eye retention rates. There are several SRS treatment platforms available, including the recently developed self-shielding gyroscopic radiosurgery (GRS) system. We report the first use of GRS in the treatment of uveal melanoma. We report the treatment of a 63-year-old female patient with a left-sided uveal melanoma. Akinesia of the ocular globe in the orbit was achieved by retrobulbar anesthesia. The treatment plan used six isocenters (three with the 10 mm and three with the 7.5 mm apertures) and 140 beams to cover 99.2% of the planning target volume (PTV) with 21 Gy at the 54% isodose line. Treatment was delivered in a single session with the GRS device. The total workflow time from retrobulbar anesthesia to completion of treatment was 122 minutes. The procedure was flawless, clinically well tolerated by the patient, and reliably performed in an outpatient setting, thus comparable to our published experience with robotic SRS. The evaluation of new radiosurgery treatment platforms is critical to maintaining quality standards and refining future treatments.

Pain response in single-fraction 8-Gy radiotherapy for painful non-bone-metastasis tumors: a single-center retrospective study.

The effectiveness of single-fraction 8-Gy radiotherapy for painful bone metastases has been verified in numerous randomized controlled trials. However, few reports have described the effectiveness of single-fraction 8-Gy radiotherapy in painful tumors other than bone metastases. We conducted a retrospective analysis to evaluate the pain response to single-fraction 8-Gy radiotherapy in painful non-bone-metastasis tumors. We included patients who had received single-fraction 8-Gy radiotherapy for such tumors between January 2017 and December 2022, excluding those with brain metastases, hematological tumors and those who received re-irradiation. Pain response assessment was based on the best responses documented in the medical records and conducted by two radiation oncologists. A total of 36 eligible patients were included in this study. The irradiation sites included primary lesions in eight patients, lymph node metastases in eight, muscle metastases in seven, pleural dissemination in four, skin/subcutaneous metastases in four and other sites in five. Pain response was assessed in 24 patients after radiotherapy. Pain response rate was 88% in evaluable patients; 21 of the 24 patients experienced response. The median assessment date for pain response was 37 days (range: 8-156 days) after radiotherapy. Re-irradiation was performed in four patients (11%). Single-fraction 8-Gy radiotherapy seemed to be a promising treatment option for painful non-bone-metastasis tumors and warrants further investigation.

21 Gy single fraction prostate HDR brachytherapy: 5-year results of a single institution prospective pilot study.

PURPOSE: To present the outcome and toxicity results of a prospective trial of 21 Gy single fraction high-dose-rate (HDR) brachytherapy for men with low- or intermediate-risk prostate cancer. METHODS AND MATERIALS: Patients were treated according to an IRB-approved prospective study of single fraction HDR brachytherapy. Eligible patients had low- or intermediate-risk prostate cancer with tumor stage ≤ T2b, PSA ≤ 15, and Gleason score ≤ 7. Patients underwent trans-rectal ultrasound-guided trans-perineal implant of the prostate followed by single fraction HDR brachytherapy to a dose of 21 Gy. The primary endpoint was grade ≥ 2 urinary/GI toxicity rates. RESULTS: Twenty-six patients were enrolled with a median follow up of 5.1 years and median age of 64 years. 88.5% of patients had T1 disease, 15.4% had Gleason score 6 (84.6% Gleason 7), and median pre-treatment PSA was 5.0 ng/mL. Acute and chronic grade ≥ 2 urinary toxicity rates were 38.5% and 38.5%, respectively. There were no grade ≥ 2 acute or chronic GI toxicities. Six (23.1%) patients experienced biochemical failure, six (23.1%) patients experienced radiographic local failure, and five (19.2%) patients had biopsy-proven local failure. No patients developed regional lymph node recurrence or distant metastasis. 5-year overall survival and cause-specific survival were 96.2% and 100%, respectively. CONCLUSIONS: 21 Gy single fraction HDR brachytherapy was associated with modestly higher-than-anticipated chronic urinary toxicity, as well as high biochemical and local failure rates. The results from this prospective pilot study do not support the use of this regimen in standard clinical practice.

Evaluation of Different Regimens of Palliative Radiation Therapy for Symptomatic Bone Metastases: An Audit From a Tertiary Care Hospital in Jharkhand, India.

Background This study aimed to assess the efficacy of different radiation therapy regimens in treating patients with symptomatic bone metastases. Methodology A retrospective study was conducted by assigning patients with symptomatic bone metastases from different primary cancers into three groups, namely, Arms A, B, and C. The radiation dose delivered in each arm was as follows: 8 Gray (Gy) in a single fraction for Arm A, 20 Gy in five fractions at the rate of 4 Gy per fraction for Arm B, and 30 Gy in 10 fractions at the rate of 3 Gy per fraction for Arm C. Each arm consisted of 15 patients. A comparison was conducted across all three arms to evaluate pain relief based on the Visual Analog Scale (VAS), performance score improvement based on the Eastern Cooperative Oncology Group (ECOG), and analgesic requirement based on the World Health Organization (WHO) step ladder at one week, one month, and three months. Results The pain relief was measured using the VAS in three different arms, i.e., Arm A, B, and C. After one week, the pain relief was 66.67%, 60%, and 60%, respectively. After one month, it was 73.33% in all three arms. At three months, it was 80%, 86.67%, and 86.67%, respectively. The study also measured the improvement in the ECOG performance score. The improvement in all three arms was 60% after one week and 66.67% in Arm A and 73.33% in Arms B and C after one month. After three months, the improvement was 73.33%, 80%, and 80% in Arms A, B, and C, respectively. The decrease in analgesic usage was also measured in all three arms. After one week, it was 60% in all three arms. After one month, it was 66.67%, 73.33%, and 73.33% in Arms A, B, and C, respectively. At three months, it was 73.33%, 80%, and 80% in Arms A, B, and C, respectively. No significant statistical difference was found between the three arms. Conclusions The efficacy of a single 8 Gy arm was almost equivalent to that of other arms of multifractionated regimens in terms of improvement in pain and performance score and decreased use of analgesics for a short duration of follow-up. For high-volume cancer centers and patients with economic constraints, a single-fraction regime provides effective palliation for painful bone metastases.

ONE SHOT - single shot radiotherapy for localized prostate cancer: 18-month results of a single arm, multicenter phase I/II trial.

PURPOSE: To assess in a prospective, multicenter, single-arm phase I/II study the early safety and efficacy profile of single fraction urethra-sparing stereotactic body radiotherapy (SBRT) for men with localized prostate cancer. MATERIAL AND METHODS: Patients with low- and intermediate-risk localized prostate cancer without significant tumor in the transitional zone were recruited. A single-fraction of 19 Gy was delivered to the prostate, with 17 Gy dose-reduction to the urethra. Intrafraction motion was monitored using intraprostatic electromagnetic transponders with intra-fraction correction of displacements exceeding 3 mm. Genitourinary (GU), gastrointestinal (GI), and sexual toxicity during the first 18 months were evaluated using the CTCAE v4.0 grading scale. Quality of life was assessed using the International Prostate Symptom Score, the Expanded Prostate Cancer Index composite 26 score, and the International Index of Erectile Function score. RESULTS: Among the 45 patients recruited in 5 centers between 2017 and 2022, 43 received the single fraction without protocol deviations, and 34 had a minimal follow-up of 18 months. The worst GU toxicity was observed at day-5 after SBRT (42.5 % and 20 % with grade 1 and 2, respectively), returning to baseline at week-12 and month-6 (<3% with grade 2), with a 12 % grade 2 flare at month 18. Gl toxicity was mild in the acute phase, with no grade ≥ 2 events (12 % grade 1 at month 6). Grade-3 proctitis was observed in one patient at month 12, with < 3 % grade 2 toxicity at month 18. Mean GU and GI bother scores showed a decline at day 5, a complete recovery at month 6, and a flare between month 12 and 18. Mean PSA dropped from 6.2 ng/ml to 1.2 ng/ml at month 18 and 0.7 ng/ml at month 24. After a median follow-up time of 26 months, 3 biochemical failures (7 %) were observed at month 17, 21 and 30. CONCLUSIONS: In this multicenter phase I/II trial, we demonstrated that a 19 Gy single-fraction urethra-sparing SBRT is feasible and associated with an acceptable toxicity rate, mostly returning to the baseline at week-12 and with a symptoms flare between months 12 and 18. Longer follow-up is needed to assess the potential long-term adverse effects and the disease control efficacy.

Single vs. multiple fraction non-inferiority trial of stereotactic ablative radiotherapy for the comprehensive treatment of oligo-metastases/progression: SIMPLIFY-SABR-COMET.

BACKGROUND: Radiotherapy delivery regimens can vary between a single fraction (SF) and multiple fractions (MF) given daily for up to several weeks depending on the location of the cancer or metastases. With limited evidence comparing fractionation regimens for oligometastases, there is support to explore toxicity levels to nearby organs at risk as a primary outcome while using SF and MF stereotactic ablative radiotherapy (SABR) as well as explore differences in patient-reported quality of life and experience. METHODS: This study will randomize 598 patients in a 1:1 ratio between the standard arm (MF SABR) and the experimental arm (SF SABR). This trial is designed as two randomized controlled trials within one patient population for resource efficiency. The primary objective of the first randomization is to determine if SF SABR is non-inferior to MF SABR, with respect to healthcare provider (HCP)-reported grade 3-5 adverse events (AEs) that are related to SABR. Primary endpoint is toxicity while secondary endpoints include lesional control rate (LCR), and progression-free survival (PFS). The second randomization (BC Cancer sites only) will allocate participants to either complete quality of life (QoL) questionnaires only; or QoL questionnaires and a symptom-specific survey with symptom-guided HCP intervention. The primary objective of the second randomization is to determine if radiation-related symptom questionnaire-guided HCP intervention results in improved reported QoL as measured by the EuroQoL-5-dimensions-5levels (EQ-5D-5L) instrument. The primary endpoint is patient-reported QoL and secondary endpoints include: persistence/resolution of symptom reporting, QoL, intervention cost effectiveness, resource utilization, and overall survival. DISCUSSION: This study will compare SF and MF SABR in the treatment of oligometastases and oligoprogression to determine if there is non-inferior toxicity for SF SABR in selected participants with 1-5 oligometastatic lesions. This study will also compare patient-reported QoL between participants who receive radiation-related symptom-guided HCP intervention and those who complete questionnaires alone. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT05784428. Date of Registration: 23 March 2023.

Outcomes of omega variant keystone flap in conjunction with single fraction radiotherapy for helical keloids: A comprehensive one-year follow-up study.

BACKGROUND: Achieving esthetically pleasing results for helical keloids can be challenging. This study aims to share the results of a treatment approach for helical keloids, which involves complete excision and reconstruction using an omega variant keystone flap, followed by a single fractional radiotherapy. METHODS: The current study is a retrospective review of 25 helical keloids in 21 patients from May 2021 to March 2023. All keloid cases were excised entirely. We covered the defect with an omega variant keystone flap followed by a single fraction of 9.5 or 10 Gy radiotherapy within 24 h after surgery. The mean follow-up period was 12 months. The primary outcome was recorded as recurrence versus non-recurrence. The secondary outcome was scores assessed by the Patient and Observer Scar Assessment Scale. RESULTS: All 25 keloids in 21 patients completed the treatment protocol, with a follow-up interval of 12 months. Of these patients, 100% had successful treatment of their keloids without any keloid recurrence. The postoperative course was uneventful except for one case of early postoperative flap congestion, which was spontaneously healed without any interventions. Scores obtained from the Patient and Observer Scar Assessment Scale showed that pain, itchiness, color, stiffness, thickness, irregularity, vascularity, pigmentation, thickness, relief, and pliability significantly improved. (p < 0.001). CONCLUSIONS: We successfully reconstructed helical keloids using an omega variant keystone flap after keloid removal followed by 9.5 or 10 Gy single fractional radiotherapy without any keloid recurrence in one-year follow-ups.

Thirty-day Mortality in Palliative Radiotherapy: A Retrospective Cohort Analysis in a Single Center.

Background/Aim: Palliative radiotherapy is a critical component of cancer care aimed at symptom management and enhancing the quality of life of patients with advanced cancer. Balancing symptom relief and potential risks is pivotal in clinical decision-making. This study explored the 30-day mortality (30-DM) rate after palliative radiotherapy in a single-center setting to shed light on potential prognostic factors and safety considerations. Patients and Methods: This retrospective cohort study included patients who underwent palliative radiotherapy for various indications between March 2020 and February 2023. Data were retrieved from electronic medical records and analyzed according to ethical guidelines. The primary outcome measure was 30-DM rate, and multivariate logistic regression analysis was conducted to identify the independent predictors of 30-DM. Results: A total of 931 palliative radiotherapy sessions were administered to 601 patients, with a median of one session per patient. The cohort had a median age of 70 years, predominantly men (58%), and featured diverse primary cancer types, with lung cancer being the most prevalent (15.8%). The 30-DM rate was 12.9%. Multivariate analysis identified Karnofsky Performance Status (KPS) as the sole independent prognostic factor significantly associated with 30-DM. Conclusion: This study provides valuable insights into 30-DM rates following palliative radiotherapy. Future research should focus on prospective multicenter investigations with larger cohorts and comprehensive data collection, ultimately leading to improved risk prediction models for personalized treatment decisions in palliative radiotherapy.

Single-Fraction Stereotactic Ablative Body Radiotherapy for Primary and Extracranial Oligometastatic Cancers.

Stereotactic ablative body radiotherapy (SABR) consists of delivering high doses of ionising radiation, typically across three to eight fractions with high precision and conformity. SABR has become increasingly commonplace throughout the last quarter of a century and is offered for the treatment of various primary and metastatic tumour types. Delivering SABR in a single fraction has arisen as an appealing possibility for several reasons. These include fewer hospital visits, greater patient convenience, improved sustainability and lower costs. However, these factors must be balanced against considerations such as toxicity, side-effects and, most importantly, progression-free and overall survival. In this review we seek to analyse the results of studies looking at the efficacy of single-fraction SABR for lung, prostate, renal and pancreas primary tumours, as well as oligometastases. The tumour type to be most widely treated with single-fraction SABR is lung, but its remit continues to expand. We also look at the biological rationale underpinning SABR and how this can be extended to single-fraction regimens. Finally, we turn our attention towards the future directions of SABR and specifically single-fraction regimens. These include the possibility of combining SABR with immunotherapy and technological advances in the field, which could serve to expand the scope of SABR. We conclude by summarising the current clinical studies of single-fraction SABR.

Salvage Radiosurgery for Recurrent Cardiac Sarcoma: A Case Report.

Primary cardiac sarcoma is a rare malignant tumor that arises from the cardiac myocardium. Surgical resection is the standard of care, and median survival ranges from 6 to 12 months. The role of salvage chemotherapy and radiation is not well defined. A 53-year-old female presented with acute congestive heart failure and underwent complete surgical resection of an undifferentiated pleomorphic sarcoma of the left atrium, followed by six cycles of adjuvant doxorubicin/hydroxydaunorubicin and ifosfamide. An MRI scan demonstrated an asymptomatic, 24 mm, recurrent atrial mass. The patient was treated with frameless robotic radiation therapy over three weeks. The tumor was treated with a dose of 72 Gy in 15 fractions to the 84% isodose line. A repeat cardiac MRI at four weeks showed in-field local progression with greater protrusion into the left atrium and invasion of the left ventricle. The patient therefore elected to proceed with salvage single-fraction frameless robotic radiosurgery. 25 Gy in one fraction was prescribed to the 76% isodose line. She tolerated treatment well without any acute toxicity and was subsequently treated with a variety of chemotherapy regimens, including tyrosine kinase inhibitors (TKIs) and immunotherapy. Unfortunately, the patient relapsed with metastases in the spine and pelvis. She underwent palliative radiation therapy at multiple bony sites with a partial response. She resumed chemotherapy treatment with TKIs but passed away due to septic shock without evidence of local failure. Fractionated SBRT was ineffective at controlling our patient's cardiac sarcoma. Our patient demonstrated local control of disease at 12 months after salvage of 25 Gy in one fraction of radiosurgery without any evidence of cardiac toxicity. High-dose single-fraction radiosurgery is a reasonable palliative option for long-term local control of unresectable cardiac sarcomas.

Local control and toxicity after magnetic resonance imaging (MR)-guided single fraction lung stereotactic ablative radiotherapy.

PURPOSE: Magnetic resonance imaging (MR)-guided radiotherapy permits continuous intrafraction visualization and use of automatic triggered beam delivery, with use of smaller planning target volumes (PTV). We report on long-term clinical outcomes following MR-guided single fraction (SF) lung SABR on a 0.35 T linac. MATERIALS AND METHODS: Details of patients treated with SF-SABR for lung tumors were accessed from an ethics approved institutional database. A breath-hold 3D MR simulation scan was performed using a true FISP sequence, followed by a breath-hold 3D CT scan. The gross tumor volume (GTV) was first contoured on the breath-hold CT scan, which was then compared with contours on the 3D MR scan, before the GTV was finalized. SABR plans used step-and-shoot IMRT beams to a PTV derived by adding a 5 mm margin to the breath-hold GTV, and a 3 mm gating window was used. SABR was delivered during repeated breath-holds, using automatic beam gating with continuous visualization of the GTV in a sagittal MR plane. RESULTS: Between 2018-2022, 50 consecutive patients were treated, and 69% had a primary non-small cell lung cancer. Median PTV was 11.2 cc (range 3.9-53.5); 80% of GTV's were located ≤2.5 cm from the chest wall. Prescribed doses were 34 Gy (in 58%), 30 Gy (32%), or between 20-28 Gy (10%). After a median follow-up of 18.1 months (95% CI 12.8-23.5), the 2-year survival was 82% (89% for primary NSCLC and 62% for metastases). After a median follow-up of 16.1 months (95% CI 11.2-21.1), local recurrences developed in 2 patients (4%). The 3-year local control rate was 97%, and just 1 patient developed grade ≥3 toxicity (chest wall pain). CONCLUSION: MR-guided SF-SABR delivery to lung tumors on a 0.35 T linac, using repeated breath-holds with automatic beam gating, achieves good tumor control and low toxicity.

Assessing the impact of intrafraction motion correction on PTV margins and target and OAR dosimetry for single-fraction free-breathing lung stereotactic body radiation therapy.

The objective of this research is to investigate intrafraction motion correction on planning target volume (PTV) margin requirements and target and organ-at-risk (OAR) dosimetry in single-fraction lung stereotactic body radiation therapy (SBRT). Sixteen patients (15 with upper lobe lesions, 1 with a middle lobe lesion) were treated with single-fraction lung SBRT. Cone-beam computed tomography (CBCT) images were acquired before the treatment, between the arcs, and after the delivery of the treatment fraction. Shifts from the reference images were recorded in anterior-posterior (AP), superior-inferior (SI), and lateral (LAT) dimensions. The deviations from the reference image were calculated for 3 clinical scenarios: not applying intratreatment couch shifts and not correcting for pretreatment deviations < 3 mm ( scenario 1), not applying intratreatment couch shifts and correcting for pretreatment deviations < 3 mm ( scenario 2), and applying all pre- and intratreatment couch shifts (scenario 3). PTV margins were determined using the van Herk formalism for each scenario and maximum and average deviations were assessed. The clinical scenarios were modelled in the treatment planning system based on each patient dataset to assess target and OAR dosimetry. Calculated lower-bound PTV margins in the AP, SI, and LAT dimensions were [4.6, 3.5, 2.3] mm in scenario 1, [4.6, 2.4, 2.2] mm in scenario 2, and [1.7, 1.2, 1.0] mm in scenario 3. The margins are lower bounds because they do not include contributions from nonmotion related errors. Average and maximum intrafraction deviations were larger in the AP dimension compared to the SI and LAT dimensions for all scenarios. A unidimensional movement (several mm) in the negative AP dimension was observed in clinical scenarios 1 and 2 but not scenario 3. Average intrafraction deviation vectors were 1.2, 1.1, and 0.3 mm for scenarios 1, 2, and 3, respectively. Modelled clinical scenarios revealed that using scenario 3 yields significantly fewer treatment plan objective failures compared to scenarios 1 and 2 using a Wilcoxon signed-rank test. Intratreatment motion correction between each arc may enable reductions PTV margin requirements. It may also compensate for unidimensional negative AP movement, and improve target and OAR dosimetry.

Workflow optimization of brachytherapy-based very accelerated partial breast irradiation.

PURPOSE: For low-risk breast cancer, accelerated partial breast irradiation (APBI) is a level 1 evidence procedure. Brachytherapy based very APBI (vAPBI) makes it possible to perform adjuvant irradiation in 4 to 1 fraction. However, vAPBI organization is critical. The aim of this technical note is to report on its optimization. METHODS AND MATERIALS: To offer to low-risk breast cancer patient an efficient, simple, rapid adjuvant irradiation with a reduced number of hospital visits, a new organization of vAPBI based on a single fraction was established, merging all the different steps (from first consultation to irradiation) into a 4-5-consecutive-hour period. This therapeutic program was developed in strong collaboration with radiation oncologists, medical physicists, radiation therapists, and the medical secretary. RESULTS: After the validation of adjuvant breast irradiation, the patient was offered a telemedicine consultation with the radiation oncologist. Then, the day of vAPBI, the patient arrived at the brachytherapy unit at 08:00 AM for an in-person consultation followed by a preimplant CT scan (defining catheter number and position). After breast local anesthesia, catheter placement was performed followed by a postimplant CT scan for planning purposes. A total dose of 16 Gy in 1 fraction was delivered before removing the catheters. The patient was discharged from the brachytherapy unit around 12:30 PM with an upcoming surveillance consultation date. CONCLUSIONS: VAPBI organization optimization makes it possible to propose a short 5-h procedure from medical consultation to treatment with only one round trip. Strict organization among staff is required.

Five-Year Sustained Complete Remission With Minimal Adverse Effects Following Radiosurgery for 2-cm Brain Metastasis With Deep Eloquent Location From Lung Adenocarcinoma Despite Low Marginal Dose and High 12 Gy Volume.

In single-fraction (sf) stereotactic radiosurgery (SRS) for brain metastases (BM) from lung adenocarcinoma (LAC), a marginal dose of ≥22-24 Gy is generally deemed desirable for achieving long-term local tumor control, whereas symptomatic brain radionecrosis significantly increases when the surrounding brain volume receiving ≥12 Gy (V12 Gy) exceeds >5-10 cm3, especially in a deep location. Here, we describe a 75-year-old male with a single LAC-BM of 20 mm in diameter, with a deep eloquent location, which was treated with sfSRS followed by erlotinib, resulting in sustained local complete remission (CR) with minimal adverse radiation effect at nearly five years after sfSRS. The LAC harbored epidermal growth factor receptor (EGFR) mutation. The gross tumor volume (GTV) was defined based on contrast-enhanced computed tomography (CECT) alone. sfSRS was implemented 11 days after planning CECT acquisition. The original GTV had some under- and over-coverage of the enhancing lesion. The D98% values of corrected GTV (cGTV) (3.08 cm3) and 2-mm outside the cGTV were 18.0 Gy with 55% isodose and 14.8 Gy, respectively. The irradiated isodose volumes, including the GTV, receiving ≥22 Gy and ≥12 Gy were 2.18 cm3 and 14.32 cm3, respectively. Erlotinib was administered 13 days after sfSRS with subsequent dose adjustments over 22 months. There was a remarkable tumor response and subsequent nearly CR of the BM were observed at 2.7 and 6.3 months, respectively, with the tumor remnant being visible as a tiny cavitary lesion located in the cortex of the post-central gyrus at 56.4 months. The present case suggests the existence of: (i) extremely radio- and tyrosine kinase inhibitor (TKI)-sensitive LAC-BM for which sfSRS of ≤18 Gy combined with EGFR-TKI is sufficient for attaining long-term CR; and (ii) long-term brain tolerance following sfSRS despite high 12 Gy volume and deep eloquent location in the late 70s The moderate marginal dose of the GTV, the main location of the BM in the cerebral cortex, and the excellent tumor responses with sufficient extrication from the mass effect may render the BM immune to late adverse radiation effect.

Appropriateness of the 30-day expected mortality metric in palliative radiation treatment: a narrative review.

BACKGROUND AND OBJECTIVE: The 30-day expected mortality rate is frequently used as a metric to determine which patients benefit from palliative radiation treatment (RT). We conducted a narrative review to examine whether its use as a metric might be appropriate for patient selection. METHODS: A literature review was conducted to identify relevant studies that highlight the benefits of palliative RT in timely symptom management among patients with a poor performance status, the accuracy of predicting survival near the end of life and ways to speed up the process of RT administration through rapid response clinics. KEY CONTENT AND FINDINGS: Several trials have demonstrated substantial response rates for pain and/or bleeding by four weeks and sometimes within the first two weeks after RT. Models of patient survival have limited accuracy, particularly for predicting whether patients will die within the next 30 days. Dedicated Rapid Access Palliative RT (RAPRT) clinics, in which patients are assessed, simulated and treated on the same day, reduce the number of patient visits to the radiation oncology department and hence the burden on the patient as well as costs. CONCLUSIONS: Single-fraction palliative RT should be offered to eligible patients if they are able to attend treatment and could potentially benefit from symptom palliation, irrespective of predicted life expectancy. We discourage the routine use of the 30-day mortality as the only metric to decide whether to offer RT. More common implementation of RAPRT clinics could result in a significant benefit for patients of all life expectancies, but particularly those having short ones.

Comparison of Survival Outcomes of Single- and Five-Fraction Schedules of Stereotactic Body Radiation Therapy for Early-Stage Central or Peripheral NSCLC.

BACKGROUND: The treatment of early-stage non-small cell lung cancer (NSCLC) with stereotactic body radiation therapy (SBRT) frequently involves different fractionation schemes for peripheral and central tumors due to concerns with toxicity. We performed an observational cohort study to determine survival outcomes for patients with peripheral and central NSCLC treated with SBRT. METHODS: A single-institutional database of patients with early-stage NSCLC treated with SBRT from September 2008 to December 2018 was evaluated. Outcomes were progression-free survival (PFS), overall survival (OS), local failure (LF), nodal failure (NF), and distant failure (DF). Cox multivariable analysis (MVA), Kaplan-Meier plotting, Fine-Gray competing risk MVA, and propensity score matching were performed. RESULTS: A total of 265 patients were included with a median follow-up of 44.2 months. There were 191 (72%) and 74 (28%) patients with peripheral and central tumors treated with single-fraction SBRT to a dose of 27 Gy and five-fraction SBRT to a dose of 50 Gy, respectively. On Cox MVA, there was no difference in OS (adjusted hazards ratio (aHR) of 1.04, 95% CI of 0.74-1.46) or PFS (aHR of 1.05, 95% CI of 0.76-1.45). On Fine-Gray competing risk MVA, there were no differences in LF, NF, or DF. Propensity matching confirmed these findings. CONCLUSION: The survival outcomes of patients treated with SBRT for early-stage NSCLC were equivalent for central and peripheral tumors.

Single-fraction high-dose-rate brachytherapy: a scoping review on outcomes and toxicities for all disease sites.

Purpose: Brachytherapy is well positioned to safely deliver highly conformal single-fraction doses of radiation, which can lower costs and improve efficiency. Traditionally, high-dose-rate brachytherapy (HDR-BT) has been delivered over multiple treatments. A scoping literature review was conducted to better understand the available literature on single-fraction HDR-BT for all disease sites. Material and methods: According to preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, PubMed database was queried from 1994-2021 using the following search terms: 'brachytherapy', 'high-dose-rate', and 'single-fraction'. A total of 53 studies met our exclusion criteria. Results: Liver had the highest number of studies, with a total of 618 patients treated with doses ranging from 8 to 25 Gy. Median follow-up ranged from 11-33 months. Local control (LC) rates ranged from 37% to 98%. G3 acute/late toxicities or higher were reported in 3 patients. Prostate cancer included a total of 1,474 patients treated with doses ranging from 19 to 21 Gy. Median follow-up ranged from 20 to 72 months. Prostate specific antigen (PSA) control outcomes after definitive treatment ranged from 65% to 94%, and salvage treatments from 5% to 84%. G3 acute/late toxicities or higher ranged from 0 to 6%. Breast cancer included a total of 268 patients treated with doses ranging from 16 to 20 Gy. Median follow-up ranged from 24 to 72 months. LC rates were 100%. G3 acute toxicities or higher ranged from 0 to 6%. Regarding other cancers, conclusions were limited given the small number of patients within each respective site. Conclusions: Currently used regimens appear safe, but efficacy vary by different disease sites. Outcomes are more promising for breast and liver, while are less encouraging for prostate. Additional prospective evaluation of single-fraction HDR-BT regimens are warranted.