Effect of Prior Transurethral Prostate Resection (TURP) or Laser Enucleation (ThuLEP) on Radiotherapy-Induced Toxicity and Quality of Life in Prostate Cancer Patients Undergoing Definitive Radiotherapy.

In our study, the post-radiotherapy quality of life of prostate cancer patients who previously underwent transurethral resection of the prostate (TURP) is compared to those who had thulium laser enucleation of the prostate (ThuLEP) and those who had no prior surgery. It also aims to identify and assess risk factors affecting therapy tolerance in this patient group. We analyzed 132 patients with localized prostate cancer treated with definitive radiotherapy (RT), including 23 who had prior TURP and 19 who previously underwent ThuLEP. A total of 62% of patients underwent irradiation within 12 months after surgery. We included only patients treated with radiotherapy using the IMRT technique. Changes in patient-reported urinary toxicity were evaluated using the International Prostate Syndrome Score (IPSS) and the quality of life index of the World Health Organization (QoL/WHO-PSS) over a three-year post-radiotherapy period. Patients with prior TURP experienced significant deterioration in QoL and IPSS immediately after irradiation (p < 0.001), whereas those without previous surgery showed both less significant differences in IPSS and QoL scores. In conclusion, patients with previous TURP/ThuLEP differ from those without previous surgery in urinary quality of life and acute and chronic urinary symptom profiles after RT. The surgical technique (ThuLEP vs. TURP) and the time interval to irradiation are crucial factors affecting RT tolerance in acute and late settings. The previously operated patient group reported a significantly longer period of increased symptom burden.

A Four-dimensional Computed Tomography Generated Internal Target Volume Approach to Paediatric High Risk Neuroblastoma to Reduce Organ at Risk and Normal Tissue Irradiation.

AIMS: The magnitude of upper abdominal organ motion in children may be overestimated by current planning target volumes (PTV). A four-dimensional computed tomography (4DCT) - derived internal target volume (ITV) is frequently used in adult radiotherapy to take respiratory-related organ motion into account. In this study, the dosimetric consequences for target coverage and organs at risk from the use of an ITV approach compared to standard PTV margins in children with high-risk neuroblastoma were investigated. MATERIALS AND METHODS: 14 patients, median age 4.1 years, range 1.5 - 18.9 years, (9 midline targets, 5 lateralised) each had two dual arc volumetric modulated arc therapy (VMAT) plans (14 ×1.5 Gy) generated. One used an ITV-approach; motion information derived from 4DCT (PTV_itv) with a 5mm ITV to PTV expansion, and the other a PTV margin of 10mm from CTV to PTV (PTV_standard). Differences in absolute PTV volume and organ at risk doses are described. RESULTS: The ITV approach resulted in a highly significant reduction in PTV size of 38% (p<0.0001). For midline targets, an ITV approach resulted in a small but statistically significant reduction in combined mean kidney dose of 0.8Gy, p 0.01. Mean heart and lung dose were reduced by an average of 1 Gy with an ITV approach. Non-PTV integral dose from 30.4 Gy L to 27.8 Gy L using an ITV approach. CONCLUSION: An ITV-approach to respiratory related organ motion management in children can significantly reduce absolute PTV volumes, maintain target coverage and reduce dose delivered to normal tissue in proximity to the target. This is an essential step to maximising the benefits of highly conformal radiotherapy techniques including VMAT for this patient group, and in the future with Proton Therapy.

Stereotactic Radiation Therapy Planning, Dose Prescription and Delivery in Veterinary Medicine: A Systematic Review on Completeness of Reporting and Proposed Reporting Items.

Increasing numbers of dogs and cats with cancer are treated with stereotactic radiosurgery, stereotactic radiation therapy or stereotactic body radiotherapy (SRS, SRT or SBRT). We provide a systematic review of the current data landscape with a focus on technical and dosimetric data of stereotactic radiotherapy in veterinary oncology. Original peer-reviewed articles on dogs and cats with cancer treated with SRT were included. The systematic search included Medline via PubMed and EMBASE. The study was performed according to the Preferred Reporting Items for Systematic Reviews (PRISMA) statement. We assessed the manuscripts regarding outcome reporting, treatment planning, dose prescription, -delivery and -reporting as well as quality assurance. As of February 2024, there are 80 peer-reviewed publications on various disease entities on SRS, SRT and SBRT in veterinary medicine. Overall, we found often insufficient or highly variable technical data, with incomplete information to reproduce these treatments. While in some instances, technical factors may not impact clinical outcome, the variability found in protocols, outcome and toxicity assessments precludes accurate and reliable conclusions for a benefit of stereotactic radiotherapy for many of the treated diseases. In line with the extensive recommendations from human stereotactic radiotherapy practise, we propose a draft of reporting items for future stereotactic radiation treatments in veterinary medicine. SRS, SRT and SBRT have specific clinical and technological requirements that differ from those of standard radiation therapy. Therefore, a deep understanding of the methodologies, as well as the quality and precision of dose delivery, is essential for effective clinical knowledge transfer.

Volumetric modulated arc therapy total body irradiation improves toxicity outcomes compared to 2D total body irradiation.

Introduction: Volumetric modulated arc therapy (VMAT) total body irradiation (TBI) allows for greater organ sparing with improved target coverage compared to 2D-TBI. However, there is limited evidence of whether improved organ sparing translates to decreases in toxicities and how its toxicities compare to those of the 2D technique. We aimed to compare differences in toxicities among patients treated with TBI utilizing VMAT and 2D techniques. Methods/materials: A matched-pair single-institution retrospective analysis of 200 patients treated with TBI from 2014 to 2023 was performed. Overall survival (OS) and progression-free survival (PFS) were analyzed using the Kaplan-Meier method and compared using log-rank tests. Differences in characteristics and toxicities between the VMAT and 2D cohorts were compared using Fisher's exact test. Results: Of the 200 patients analyzed, 100 underwent VMAT-TBI, and 100 underwent 2D-TBI. The median age for VMAT-TBI and 2D-TBI patients was 13.7 years and 16.2 years, respectively (p = 0.25). In each cohort, 53 patients were treated with myeloablative regimens (8-13.76 Gy), and 47 were treated with non-myeloablative regimens (2-4 Gy). For the entire VMAT-TBI cohort, lung Dmean, kidney Dmean, and lens Dmax were spared to 60.6% ± 5.0%, 71.0% ± 8.5%, and 90.1% ± 3.5% of prescription, respectively. For the non-myeloablative VMAT-TBI cohort, testis/ovary Dmax, brain, and thyroid Dmean were spared to 33.4% ± 7.3%, 75.4% ± 7.0%, and 76.1% ± 10.5%, respectively. For 2D-TBI, lungs were spared using partial-transmission lung blocks for myeloablative regimens. The VMAT-TBI cohort experienced significantly lower rates of any grade of pneumonitis (2% vs. 12%), nephrotoxicity (7% vs. 34%), nausea (68% vs. 81%), skin (16% vs. 35%), and graft versus host disease (GVHD) (42% vs. 62%) compared to 2D-TBI patients. For myeloablative regimen patients, rates of pneumonitis (0% vs. 17%) and nephrotoxicity (9% vs. 36%) were significantly lower with VMAT-TBI versus 2D-TBI (p < 0.01). Median follow-up was 14.3 months, and neither median OS nor PFS for the entire cohort was reached. In the VMAT versus 2D-TBI cohort, the 1-year OS was 86.0% versus 83.0% (p = 0.26), and the 1-year PFS was 86.6% and 80.0% (p = 0.36), respectively. Conclusion: Normal tissue sparing with VMAT-TBI compared to the 2D-TBI translated to significantly lower rates of pneumonitis, renal toxicity, nausea, skin toxicity, and GVHD in patients, while maintaining excellent disease control.

Advanced-technique radiation therapy for nasopharyngeal carcinoma in a low resource setting: a review of treatment-related quality of life.

Background: Nasopharyngeal carcinoma (NPC) is a rare but significant public health concern, especially in Africa, with a rising global incidence. This study aimed to investigate the pattern of presentation, treatment outcomes and impact on health-related quality of life (HRQOL) of NPC patients at a tertiary institution in Lagos, Nigeria. Methodology: A retrospective review of all nasopharyngeal cancer patients (n = 125) treated at a tertiary centre in Lagos, Nigeria, from May 2019 to 2022 was done. The European Organisation for Research and Treatment of Cancer (EORTC) H&N 35 questionnaire was used to assess HRQOL at 1-year post treatment and the data were analysed using a statistical package for the social sciences v26.0. Results: Among 125 patients, the mean age was 46.21 ± 17.82 years with 76% male. Comorbidities were reported in 34 patients (27.2%), smoking history in 18 patients (14.4%) and 50 patients (40%) reported alcohol consumption. Environmental risk factors were identified in six patients (4.8%). The most prevalent histology was squamous cell carcinoma (92.8%), and stage IV was the most common stage (42.4%). Chemoradiation was the primary treatment (63.2%), with intensity-modulated radiotherapy being the most utilised approach (51.2%). Among 125 patients, 51 completed the EORTC questionnaire. Weight loss, sticky saliva, dry mouth, difficulties in swallowing and problems with the sense of taste and smell were the most severe symptoms reported by patients. In the follow-up, 79.2% of patients were reached (50.4% alive, 28.8% deceased). Mortality was significantly associated with age >65 years, weight loss at presentation and consumption of grilled/smoked food. Conclusion: The study highlights key aspects of NPC in our region including the predominance in males, advanced disease stage at presentation and persistent symptoms post-treatment. Our findings point to the need for targeted initiatives to improve early detection and quality of life for nasopharyngeal patients in the country.

Four Cases of Single-Fraction Stereotactic Body Radiation Therapy for Prostate Cancer.

Hypofractionated radiotherapy for prostate cancer has been reported to date. Here, we report on four patients with prostate cancer who were treated with single-fraction stereotactic body radiation therapy. It was conducted with reference to some previous clinical trials. The median age of the patients was 76.5 years (range: 72-89 years). All except one patient with low-risk prostate cancer received androgen deprivation therapy (ADT) before irradiation. All patients received a dose of 24 Gy in one fraction using X-ray photon beams when prostate-specific antigen (PSA) fell to low levels due to ADT. After irradiation, all patients had a gradual decline in PSA, and so far none has had a PSA recurrence. Although Grade 1-2 adverse events occurred in all cases, none of the patients showed adverse events of Grade 3 or over during the observation period.

Identifying dose constraints for the parotid ducts to minimize patient-reported xerostomia: Is conventional mean dose sparing of the parotid glands sufficient?

BACKGROUND AND PURPOSE: The aim of this study was to identify dose constraints for the parotid ducts that limit patient-reported xerostomia and estimate whether these constraints are achieved during conventional parotid gland sparing radiation therapy (PGS-RT). METHODS AND MATERIALS: Thirty-eight oropharyngeal squamous cell carcinoma patients were treated prospectively on trial with MRI sialography-guided parotid duct sparing radiation therapy (PDS-RT). PDS-RT explicitly minimizes dose to the parotid ducts in addition to PGS-RT. Parotid duct dose constraints were identified that distinguished patients reporting high and low rates of xerostomia. Atlas-based parotid duct contours were generated on a retrospective cohort of similar patients where the parotid ducts were not contoured nor explicitly spared to estimate the dose received by the parotid ducts during PGS-RT. RESULTS: Patients whose intraglandular parotid ducts or total parotid ducts were planned for a mean dose < 14 Gy and < 12 Gy, respectively, reported significantly (p < 0.01) lower rates of xerostomia at 6 and 12 months post-RT. Patients receiving PDS-RT had average total and intraglandular duct doses of 11.6  and 13.6 Gy, respectively, compared to an estimated 23.8  and 22.1 Gy, for those receiving PGS-RT (p < 0.01). Only 6% (6/108) and 20% (22/108) of patients receiving PGS-RT were estimated to meet the dose constraints for the total ducts and intraglandular ducts, respectively. CONCLUSION: Parotid duct dose thresholds exist that appear to distinguish patients with and without xerostomia. The identified dose thresholds are frequently not met in PGS-RT plans. In addition to reducing the dose to the parotid gland(s), parotid duct sparing may also further reduce xerostomia.

A Retrospective Study Evaluating the Outcomes of Conventionally Fractionated Radiation Therapy as a Treatment for Infiltrative Lipomas in Twenty-One Dogs.

Infiltrative lipomas represent a subcategorisation of rarer, potentially more aggressive, lipoma-related neoplasms. Twenty-one dogs treated with conventionally fractionated radiotherapy (CFRT) for infiltrative lipomas were included in this retrospective study. One patient had no prior surgical excision, 11 patients had one prior surgery and 9 patients had two or more surgeries prior to CFRT. Five patients (24%) had microscopic disease and 16 patients (76%) had macroscopic disease prior to treatment. A complete response or no regrowth was seen in 10 patients (48%), stable disease in 6 patients (29%) and progressive disease or regrowth in 5 patients (24%). Response to treatment of macroscopic tumours was significantly different between dogs that had one prior surgery versus two or more (p = 0.01). Dogs with a single surgery were most likely to result in stable disease compared with dogs with two or more surgeries resulting in a complete response. The dog without surgery developed progressive disease at 211 days, dogs with one surgery had a median progression or recurrence at 1369 days and dogs with two or more surgeries developed progression or recurrence at 826 days (p = 0.04). Twelve dogs were alive at the time of analysis. Overall median survival time (MST) was 1694 days. The prior number of surgeries did not significantly affect MST. While survival time is comparable to previous reports, the number of patients with progressive disease or recurrence of previous microscopic disease requires more investigation into the most appropriate protocol, dose and treated field size.

Recent developments in the field of radiotherapy for the management of lung cancer.

Lung cancer has a poor prognosis, and further improvements in outcomes are needed. Radiotherapy plays an important role in the treatment of unresectable lung cancer, and there have been recent developments in the field of radiotherapy for the management of lung cancer. However, to date, there have been few reviews on the improvement in treatment outcomes associated with high precision radiotherapy for lung cancer. Thus, this review aimed to summarize the recent developments in radiotherapy techniques and indicate the future directions in the use of radiotherapy for lung cancer. Stereotactic body radiotherapy (SBRT) for unresectable stage I lung cancer has been reported to improve local control rates without severe adverse events, such as radiation pneumonitis. For locally advanced lung cancer, a combination of chemoradiotherapy and adjuvant immune checkpoint inhibitors dramatically improves treatment outcomes, and intensity-modulated radiotherapy (IMRT) enables safer radiation therapy with less frequent pneumonitis. Particle beam therapy, such as carbon-ion radiotherapy and proton beam therapy, has been administered as advanced medical care for patients with lung cancer. Since 2024, it has been covered under insurance for early stage lung cancer with tumors ≤ 5 cm in size in Japan. In addition to chemotherapy, local ablative radiotherapy improves treatment outcomes in patients with oligometastatic stage IV lung cancer. A particular problem with radiotherapy for lung cancer is that the target location changes with respiratory motion, and various physical methods have been used to control respiratory motion. Recently, coronavirus disease has had a major impact on lung cancer treatment, and cancer treatment during situations, such as the coronavirus pandemic, must be performed carefully. To improve treatment outcomes for lung cancer, it is necessary to fully utilize evolving radiotherapy modalities, and the role of radiotherapy in lung cancer treatment is expected to increase.

Prognostic implications of HIF-1α expression in anal squamous cell carcinoma treated with intensity-modulated radiotherapy (IMRT).

Background: Hypoxia-inducible factor-1α (HIF-1α) is a crucial transcription factor activated under hypoxic conditions, known to regulate genes associated with tumor survival, progression, and response to therapy. This study aimed to evaluate the prognostic significance of HIF-1α expression in patients with anal squamous cell carcinoma (ASCC) undergoing chemoradiation therapy. Methods: We conducted a retrospective analysis of 28 ASCC patients treated with intensity-modulated radiotherapy (IMRT) at our center from 2009 to 2022. HIF-1α expression was assessed via immunohistochemistry on formalin-fixed paraffin-embedded tissue specimens. Quantitative analysis of HIF-1α expression was performed, and its relationship with clinical outcomes, including disease-free survival (DFS), locoregional relapse-free survival (LRRFS), and overall survival (OS), was examined using Cox regression models. Furthermore, ASCC tissue specimens from 17 patients were analyzed for potential PIK3CA mutations using Sanger sequencing. Results: High HIF-1α expression was significantly associated with poorer DFS (p = 0.005), LRRFS (p = 0.012), and OS (p = 0.009). HIF1α expression was marginally significantly higher in males compared to females (p = 0.056) while there was no significant difference found based on tumor stage or p16 status. However, a positive correlation was identified between BMI and HIF-1α levels (Pearson correlation r = 0.5, p = 0.0084), suggesting a link between metabolic status and tumor hypoxia. Only one patient exhibited a PIK3CA mutation, preventing a reliable assessment of its correlation with HIF-1α expression. Conclusion: Our findings underscore the importance of HIF-1α as a potential biomarker for predicting survival outcomes in ASCC patients treated with chemoradiation. The association between higher BMI and increased HIF-1α expression may provide insights into the interplay between metabolic health and tumor biology in ASCC. Further studies with larger cohorts are needed to validate these findings and explore targeted therapies focusing on HIF-1α modulation.

Half body irradiation (HBI) for bone metastases in the modern radiotherapy technique era - A systematic review.

Bone metastases (BMs) are the most common cause of cancer-related pain and radiation therapy plays a key role in treating pain caused by it. The half-body irradiation (HBI) is a modality that can be used to treat patients with multiple painful BMs. In the modern era, concerns about toxicity and the availability of new agents requiring robust bone marrow function have limited the use of HBI in advanced cancer. Concerns about HBI toxicity stem from outdated techniques; modern methods like volumetric modulated arc therapy (VMAT) and helical tomotherapy now allow safer irradiation of complex target volumes. We conducted a systematic review to present updated information about HBI efficacy and potential toxicity. Pain relief usually occurs very quickly 2-3 weeks after HBI. The overall pain response rate was high in all the series, accounting for a median of 84 % (75.6-89 %), with a median of 36 % complete pain response. The toxicity is usually limited to G1/G2, with very rare G3 cases. More than 50 % of patients can reduce analgesic intake after HBI. Additionally, with modern radiotherapy techniques, quality of life is improved in most patients. HBI is a safe and effective method and should once again be reconsidered for more frequent use.

High buttocks supine position to reduce small bowel exposure in gynecological radiotherapy.

PURPOSE: To minimize radiation exposure to the small bowel (SB) in patients undergoing treatment for gynecological tumors by adopting a comfortable positioning method. METHODS AND PATIENTS: All 76 women undergoing Intensity-Modulated Radiation Therapy (IMRT) were included in this study. Patients were immobilized in a supine position using a vacuum bag and thermoplastic cast formation. In the trial group (n = 36), patients raised their buttocks and a solid foam pad was placed under the sacral tail before immobilization. The control group (n = 40) received treatment in the standard supine position. The SB was delineated from the pubic symphysis to the total iliac bifurcation in computed tomography (CT) scans. RESULT: In the trial group, a significant reduction in SB volume within the pelvic cavity was observed (mean 399.17 ± 158.7 cc) compared to the control group (mean 547.48 ± 166.9 cc), with a p-value less than 0.001. The trial group showed a statistically significant reduction in the absolute volume of irradiated SB at each dose, ranging from the low dose (10 Gy) to the high dose (45 Gy). In the control group, a negative correlation was found between SB and bladder volumes (R = -0.411, P = 0.008), whereas in the trial group, this correlation was weaker (R = -0.286, P = 0.091), with no significant relationship observed between bladder volume and SB. CONCLUSION: The high buttocks supine position effectively reduces SB radiation exposure without the need for bladder distension. This positioning method holds promise for reducing SB irradiation in various pelvic tumors.

Comparing Dosimetry of Heart and Left Anterior Descending Artery Exposure in Carcinoma Esophagus Patients: Volumetric Arc Therapy Versus Intensity-Modulated Radiotherapy.

Introduction Esophageal cancer remains a leading cause of cancer-related mortality worldwide, with chemoradiotherapy being a cornerstone of its treatment. Ensuring precise radiation delivery is critical, as it minimizes exposure to surrounding healthy tissues, particularly vital structures like the heart and the left anterior descending artery (LAD). Volumetric arc therapy (VMAT) and intensity-modulated radiotherapy (IMRT) are two advanced radiotherapy techniques that offer enhanced dose conformity and reduced toxicity. This study conducts a retrospective dosimetric analysis to compare the effectiveness of VMAT and IMRT in sparing cardiac substructures and the LAD in patients with carcinoma of the esophagus. Methods Ten patients with middle-third esophageal cancer were treated using the VMAT technique with two coplanar arcs. These patients were retrospectively re-planned with IMRT using 7-9 fields on the Varian TrueBeam linear accelerator between June 2023 and December 2023. VMAT planning involved a two-phase approach: 45 Gy in 25 fractions followed by a boost of 5.4 Gy in three fractions. Dose-volume histograms were analyzed and compared for the planning target volume (PTV), heart and its substructures (including the right atrium, right ventricle, left atrium, and left ventricle), and the LAD. Statistical significance was determined using paired t-tests with a significance level set at P < 0.05. Results PTV coverage was comparable between VMAT and IMRT. VMAT resulted in higher low-dose exposure (V5 and V10) but offered better sparing at moderate doses (V20 and V40) for the heart. The LAD benefited from reduced high-dose exposure with VMAT. For other cardiac substructures, VMAT generally showed higher low-dose exposure but provided superior sparing at moderate doses compared to IMRT. Conclusions VMAT offers notable dosimetric advantages in sparing critical cardiac structures compared to IMRT for treating patients with middle third esophageal cancer. Long-term follow-up studies are needed to assess how these dosimetric benefits influence coronary artery disease and other cardiac complications.

Portability of IMRT QA between matched linear accelerators.

PURPOSE: To determine if patient-specific IMRT quality assurance can be measured on any matched treatment delivery system (TDS) for patient treatment delivery on another. METHODS: Three VMAT plans of varying complexity were created for each available energy for head and neck, SBRT lung, and right chestwall anatomical sites. Each plan was delivered on three matched Varian TrueBeam TDSs to the same Scandidos Delta4 Phantom+ diode array with only energy-specific device calibrations. Dose distributions were corrected for TDS output and then compared to TPS calculations using gamma analysis. Round-robin comparisons between measurements from each TDS were also performed using point-by-point dose difference, median dose difference, and the percent of point dose differences within 2% of the mean metrics. RESULTS: All plans had more than 95% of points passing a gamma analysis using 3%/3 mm criteria with global normalization and a 20% threshold when comparing measurements to calculations. The tightest gamma analysis criteria where a plan still passed > 95% were similar across delivery systems-within 0.5%/0.5 mm for all but three plan/energy combinations. Median dose deviations in measurement-to-measurement comparisons were within 0.7% and 1.0% for global and local normalization, respectively. More than 90% of the point differences were within 2%. CONCLUSION: A set of plans spanning available energies and complexity levels were delivered by three matched TDSs. Comparisons to calculations and between measurements showed dose distributions delivered by each TDS using the same DICOM RT-plan file meet tolerances much smaller than typical clinical IMRT QA criteria. This demonstrates each TDS is modeled to a similar accuracy by a common class (shared) beam model. Additionally, it demonstrates that dose distributions from one TDS show small differences in median dose to the others. This is an important validation component of the common beam model approach, allowing for operational improvements in the clinic.

Comparing long-term efficacy and safety of GP versus TPF sequential chemoradiotherapy for locoregionally advanced nasopharyngeal carcinoma: a propensity score-matched analysis.

PURPOSE: To evaluate the long-term efficacy and safety of GP and TPF sequential chemotherapy regimens in patients with locoregionally advanced nasopharyngeal carcinoma (LA-NPC). METHODS: From 2005 to 2016, a total of 408 LA-NPC patients treated with GP or TPF sequential chemoradiotherapy were retrospectively included. Propensity Score Matching (PSM) was employed to balance the baseline variables. Survival outcomes and acute toxicities were compared between both groups. RESULTS: A total of 230 patients were selected by 1:1 PSM. At a median follow-up of 91 months, no significant differences were observed between the matched GP and TPF groups regarding 5-year overall survival, progression-free survival, distant metastasis-free survival, and locoregionally relapse-free survival (83.4% vs. 83.4%, P = 0.796; 75.6% vs. 68.6%, P = 0.301; 86.7% vs. 81.1%, P = 0.096; and 87.4% vs. 87.2%, P = 0.721). Notable disparities in adverse effects were identified, with higher incidences of grade 3/4 thrombocytopenia in the GP group while grade 3/4 leukopenia and neutropenia in the TPF group. Though not recorded in our cohort, combined with the FAERS database, thrombotic adverse reactions are a concern for the GP regimen, while the TPF regimen requires vigilance for life-threatening adverse reactions such as septic shock, acute respiratory distress syndrome, and laryngeal edema. CONCLUSION: No significant difference in long-term outcomes was observed between the GP and TPF sequential chemotherapy regimens for LA-NPC. Differences in adverse effects should be noted when choosing the regimen.

Circulating M-MDSC Levels as an Assessment Marker for Post-Treatment Tumor Progression in Recurrent HNC Patients Following Radiation Therapy: A Case Series.

Background: In advanced head and neck cancer (HNC) patients, 50-60% experience loco-regional relapse and distant metastasis. Boron neutron capture therapy (BNCT) has shown remarkable therapeutic response in recurrent HNC, but there is still a 70% chance of local recurrence. This study aimed to identify a suitable liquid biomarker to assess patient response following BNCT. Myeloid-derived suppressor cells (MDSCs) are immune-suppressive cells that inhibit cytotoxic T cells. Circulating MDSC levels have been linked to the clinical stage and prognosis in HNSCC. Methods: Five patients with recurrent head and neck cancer underwent a treatment regimen that commenced with BNCT, followed by fractionated image-guided intensity-modulated radiotherapy (IG-IMRT). Liquid biopsy analysis via flow cytometry and tumor volume analysis by clinical imaging were conducted at three stages: before BNCT, before the first fraction of IG-IMRT, and one month after the last fraction of IG-IMRT. Results: Compared to other MDSC subtypes, monocytic MDSCs (M-MDSCs) exhibited a notable correlation with tumor volume. This strong correlation was observed at all testing time points except one month after BNCT treatment. Conclusions: This case series highlights a strong link between tumor size and circulating M-MDSC levels before BNCT and one month after the last IG-IMRT treatment in recurrent head and neck cancer patients. These results suggest that the level of circulating M-MDSCs could be a marker for monitoring tumor progression in recurrent HNC patients following radiation therapy, including BNCT.

Is clinical target volume necessary for locally advanced non-small cell lung cancer treated with 4D-CT intensity-modulated radiation therapy.

BACKGROUND: A dosimetric evaluation is still lacking in terms of clinical target volume (CTV) omission in stage III patients treated with 4D-CT Intensity-Modulated Radiation Therapy (IMRT). METHODS: 49 stage III NSCLC patients received 4D-CT IMRT were reviewed. Target volumes and organs at risk (OARs) were re-delineated. Four IMRT plans were conducted retrospectively to deliver different prescribed dose (74 Gy-60 Gy), and with or without CTV implementation. Dose and volume histogram (DVH) parameters were collected and compared. RESULTS: In the PTV-g 60 Gy plan (PTV-g refers to the PTV generated from the internal gross tumor volume), only 5 of 49 patients had the isodose ≥ 50 Gy line covering at least 95% of the PTV-c (PTV-c refers to the PTV generated from the internal CTV) volume. When the prescribed dose was elevated to 74 Gy to the PTV-g, 33 of 49 patients could have the isodose ≥ 50 Gy line covering at least 95% of the PTV-c volume. In terms of OARs protection, the SIB-IMRT plan showed the lowest value of V5, V20, and mean dose of lung, had the lowest V55 of esophagus, and the lowest estimated radiation doses to immune cells (EDIC). The V20, V30, and mean dose of heart was lower in the simultaneous integrated boost (SIB) IMRT (SIB-IMRT) plan than that of the PTV-c 60 Gy plan. CONCLUSIONS: CTV omission was not suitable for stage III patients when the prescribed dose to PTV-g was 60 Gy in the era of 4D-CT IMRT. CTV omission plus high dose to PTV-g (74 Gy for example) warranted further exploration. The SIB-IMRT plan had the best protection to normal tissue including lymphocytes, and might be the optimal choice.

Long-term Results of Hypofractionated Radiotherapy With Intra-prostatic Boosts in Men With Intermediate- and High-risk Prostate Cancer: A Phase II Trial.

AIMS: In the conventionally fractionated phase III FLAME prostate trial, focal boosts improved local control and biochemical disease-free survival (bDFS). We explored the toxicity and effectiveness of a moderately hypofractionated schedule with focal boosts. MATERIAL AND METHODS: BIOPROP20 is a phase II single-arm non-randomised trial for intermediate- to very high-risk localised prostate cancer patients with bulky tumour volumes. Multi-parametric magnetic resonance imaging (MRI) and 18F-choline positron emission tomography-computed tomography (PET-CT) scans were used for staging and boost volume definition. Patients were treated with 60Gy in 20 fractions with a boost dose up to 68Gy. Five patients with positive lymph nodes on the PET-CT scan received radiotherapy to pelvic lymph nodes (45Gy to elective nodes, boosted up to 50Gy to involved nodes). Primary outcomes were acute (≤18 weeks) and late urinary and gastrointestinal toxicity, prospectively recorded up to 5 years with Common Terminology Criteria for Adverse Events v4 (CTCAE). Secondary outcomes were biochemical or clinical progression, metastasis-free survival (MFS), and overall survival (OS). RESULTS: 61 patients completed radiotherapy with hormone therapy (range: 6-36 months). Cumulative acute and late gastrointestinal toxicity was low at 6.6% and 5.0%, respectively. Cumulative acute and late urinary toxicity was 49.2% and 30.1%, respectively; the prevalence reduced to 5.9% at 5 years. At 5 years: 6 patients had biochemical progression (bDFS: 88.5%; 95% CI: 80.2-97.6%), the MFS was 82.4% (95% CI: 73.0-92.9%), 5 patients died (OS: 91.2%; 95% CI: 84.1-98.9%), one with prostate cancer. The prostate, boost, nodal planning volumes, and the organs at risk (rectum, bowel, urethra, and bladder) met the optimal protocol dose constraints. There was a trend to increased urinary toxicity with increasing urethral (RR: 1.95, 95% CI: 0.73-5.22, p = 0.18), but not bladder dose. CONCLUSION: Focal boosts with a 20 fraction hypofractionated prostate radiotherapy schedule are associated with an acceptable risk of gastrointestinal and urinary toxicity and achieve good cancer control. GOV IDENTIFIER: NCT02125175.

Innovative regression model-based decision support tool for optimizing radiotherapy techniques in thoracic esophageal cancer.

Background: Modern radiotherapy exemplified by intensity-modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT), has transformed esophageal cancer treatment. Facing challenges in treating thoracic esophageal cancer near vital organs, this study introduces a regression model-based decision support tool for the optimal selection of radiotherapy techniques. Methods: We enrolled 106 patients diagnosed with locally advanced thoracic esophageal cancer in this study and designed individualized IMRT and VMAT radiotherapy plans for each patient. Detailed dosimetric analysis was performed to evaluate the differences in dose distribution between the two radiotherapy techniques across various thoracic regions. Single-factor and multifactorial logistic regression analyses were employed to establish predictive models (P1 and P2) and factors such as TLV/PTV ratio. These models were used to predict the compliance and potential advantages of IMRT and VMAT plans. External validation was performed in a validation group of 30 patients. Results: Using predictive models, we developed a data-driven decision support tool. For upper thoracic cases, VMAT plans were recommended; for middle/lower thoracic cases, the tool guided VMAT/IMRT choices based on TLV/PTV ratio. Models P1 and P2 assessed IMRT and VMAT compliance. In validation, the tool showed high specificity (90.91%) and sensitivity (78.95%), differentiating IMRT and VMAT plans. Balanced performance in compliance assessment demonstrated tool reliability. Conclusion: In summary, our regression model-based decision support tool provides practical guidance for selecting optimal radiotherapy techniques for thoracic esophageal cancer patients. Despite a limited sample size, the tool demonstrates potential clinical benefits, alleviating manual planning burdens and ensuring precise, individualized treatment decisions for patients.

A retrospective study on the effectiveness of intensity modulated radiation therapy for thyroid associated ophthalmopathy at a single institute.

Thyroid-associated ophthalmopathy (TAO) is a hallmark autoimmune condition, and the treatment of TAO requires a multidisciplinary approach. Radiation therapy (RT) is a viable treatment option for active TAO, IMRT is a more precise technology in radiation oncology. This study aims to evaluate the efficacy, feasibility, and safety of orbital intensity-modulated radiation therapy (IMRT) in the treatment of TAO. A single-center retrospective analysis was conducted, including patients diagnosed with moderate to severe active TAO at the Department of Radiation Oncology, Peking University Third Hospital, from October 2020 to October 2023, who had poor responses to corticosteroid treatment. These patients subsequently received IMRT treatment, followed by a period of follow-up and retrospective analysis. The study focused on the outcomes of treatment efficacy, safety, and acute toxic reactions induced by radiation therapy. Improvements in clinical activity score (CAS) at 4 and 12 months were considered as primary and secondary study endpoints, respectively, along with the incidence rate of adverse events. The median follow-up period was 12 months. The median follow-up time after radiation therapy was 12 months. There was no statistically significant difference in CAS between before and 4 months after radiation therapy (CAS: 5.53 ± 2.07 vs.4.68 ± 2.62; R squared: 0.21; 95% CI: - 1.01-0.02; P = 0.054). However, there was a significant reduction in CAS 12 months post-treatment compared to pre-treatment (CAS: 5.53 ± 2.07 vs. 3.06 ± 2.38; R squared: 0.66; 95% CI: 3.42 - 1.52; P < 0.001). The CAS showed a progressively decreasing trend at both 4 months and 12 months post-treatment. In the combined radiotherapy with glucocorticoid treatment group, a statistically significant difference was found between the CAS before treatment and 12 months after radiotherapy (CAS: 6.38 ± 2.00 vs. 3.88 ± 2.85; R squared: 0.66; 95% CI - 4.11 to 0.89; P = 0.008). In the radiotherapy alone group, a statistically significant difference was found between the CAS before treatment and 12 months after radiotherapy (CAS: 4.78 ± 1.92 vs. 2.33 ± 1.73; R squared: 0.66; 95% CI - 3.89 to 1.00; P = 0.005). A few patients experienced Grade I periorbital edema, conjunctival congestion, and dry eye syndrome, but no adverse events such as cataracts, radiation retinopathy, or radiation-induced optic neuropathy were observed by the end of the follow-up period. Orbital IMRT is an effective treatment modality for moderate to severe active TAO, demonstrating significant efficacy even in patients who had not achieved success with previous treatments such as corticosteroids. This retrospective study was approved by the Ethics Committee of Peking University Third Hospital. The permit number was M2024220 and data of registration was April I, 2024.