UNASSIGNED:
UNASSIGNED: This multicenter study aimed to retrospectively evaluate the impact of high boost simultaneous integrated boost (SIB) to pathologic lymph nodes compared to Sequential boost (Seq) in patients with locally advanced cervical cancer (LACC).
UNASSIGNED: 97 patients with pelvic and/or para-aortic (PAo) node-positive LACC treated by definitive chemoradiation were included. Two groups were analyzed: Sequential boost group and simultaneous integrated boost (SIB) group. Endpoints were Distant Recurrence Free Survival (DRFS), Recurrence Free Survival (RFS), Overall Survival (OS), locoregional pelvic and PAo control and toxicities.
UNASSIGNED: 3-years DRFS in SIB and Seq groups was 65% and 31% respectively (log-rank p < 0.001). 3-years RFS was 58% and 26% respectively (log-rank p = 0.009). DRFS prognostic factors in multivariable analysis were SIB, PAo involvement and maximum pelvic node diameter ≥ 2cm. Adenocarcinoma histology and absence of brachytherapy tended to be prognostic factors. SIB provided the best pelvic control at first imaging with 97%. There was no significant difference in terms of toxicities between groups.
UNASSIGNED: Nodal SIB seems to be unavoidable in the treatment of node-positive LACC. It provides the best DRFS, RFS and pelvic control without additional toxicity, with a shortened treatment duration.

UNASSIGNED: Severe lymphopenia (SLP) has emerged as a significant prognostic factor in glioblastoma. Intensity-modulated radiation therapy (IMRT)-based radiation therapy (RT) is suggested to minimize the risk of SLP. This study aimed to evaluate SLP incidence based on multi-institutional database in patients with GBM treated with IMRT and develop a predictive nomogram.
UNASSIGNED: This retrospective study reviewed data from 348 patients treated with IMRT-based concurrent chemoradiation therapy (CCRT) at two major hospitals from 2016 to 2021. After multivariate regression analysis, a nomogram was developed and internally validated to predict SLP risk.
UNASSIGNED: During treatment course, 21.0% of patients developed SLP and SLP was associated with poor overall survival outcomes in patients with GBM. A newly developed nomogram, incorporating gender, pre-CCRT absolute lymphocyte count, and brain mean dose, demonstrated fair predictive accuracy (AUC 0.723).
UNASSIGNED: This study provides the first nomogram for predicting SLP in patients with GBM treated with IMRT-based CCRT, with acceptable predictive accuracy. The findings underscore the need for dose optimization and radiation planning to minimize SLP risk. Further external validation is crucial for adopting this nomogram in clinical practice.

Patients with pediatric cancer receive radiotherapy to cure several types of cancer, requiring computed tomography simulation (CT sim) for precise treatment. However, there is currently no suitable framework to reduce the inherent delays in CT sim. The present study aimed to identify the underlying causes of the delays in CT sim regarding three different time periods (duration of patient admission to CT sim, diagnosis to treatment and CT sim to treatment) among patients with pediatric cancer. A total of 58 patients with pediatric cancer who received radiation therapy under anesthesia at King Abdulaziz University Hospital (Jeddah, Saudi Arabia) between 2016 and 2021 (60 months) were included in the current study. The underlying cause of delays regarding three separate time periods was determined according to patient type, diagnosis, therapy type and year of diagnosis. The CT sim processing time averaged 73 days and was received by patients after 28.96±28.5 days. The major delays in terms of frequency and length of duration between different time points such as patient admission and CT sim, interval between diagnosis and treatment, and duration between CT sim and therapy were (mean±SD) 37.13±29.9, 58.08±24.9 and 28.15±7.9 days, respectively. Machine availability, instability of the patients\' medical condition and intensity-modulated radiation therapy (IMRT) caused 66.6% of the delays. In conclusion, outpatients may experience CT sim delays. Machine availability, conditions of patients and IMRT treatment were the major reasons to cause the delay in CT sim. Strategies should be employed to prevent CT sim delays and improve patient experience.

BACKGROUND: Classical radiation protocols are guided by physical dose delivered homogeneously over the target. Protocols are chosen to keep normal tissue complication probability (NTCP) at an acceptable level. Organs at risk (OAR) adjacent to the target volume could lead to underdosage of the tumor and a decrease of tumor control probability (TCP). The intent of our study was to explore a biology-based dose escalation: by keeping NTCP for OAR constant, radiation dose was to be maximized, allowing to result in heterogeneous dose distributions.
METHODS: We used computed tomography datasets of 25 dogs with brain tumors, previously treated with 10x4 Gy (40 Gy to PTV D50). We generated 3 plans for each patient: A) original treatment plan with homogeneous dose distribution, B) heterogeneous dose distribution with strict adherence to the same NTCPs as in A), and C) heterogeneous dose distribution with adherence to NTCP <5%. For plan comparison, TCPs and TCP equivalent doses (homogenous target dose which results in the same TCP) were calculated. To enable the use of the generalized equivalent uniform dose (gEUD) metric of the tumor target in plan optimization, the calculated TCP values were used to obtain the volume effect parameter a.
RESULTS: As intended, NTCPs for all OARs did not differ from plan A) to B). In plan C), however, NTCPs were significantly higher for brain (mean 2.5% (SD±1.9, 95%CI: 1.7,3.3), p<0.001), optic chiasm (mean 2.0% (SD±2.2, 95%CI: 1.0,2.8), p=0.010) compared to plan A), but no significant increase was found for the brainstem. For 24 of 25 of the evaluated patients, the heterogenous plans B) and C) led to an increase in target dose and projected increase in TCP compared to the homogenous plan A). Furthermore, the distribution of the projected individual TCP values as a function of the dose was found to be in good agreement with the population TCP model.
CONCLUSIONS: Our study is a first step towards risk-adaptive radiation dose optimization. This strategy utilizes a biologic objective function based on TCP and NTCP instead of an objective function based on physical dose constraints.

Self-care demonstrated efficacy in preventing severe acute radiation dermatitis among patients with head and neck squamous cell carcinoma undergoing chemoradiotherapy (CRT). This prospective trial aimed to confirm the feasibility and safety of transcutaneous electrical sensory stimulation while examining the relationship between changes in self-care behavior through supportive care interventions and the severity of acute radiation dermatitis during CRT. Patients underwent assessments for dermatitis grading (Grades 1 to ≥3) and were interviewed regarding self-care practices. The self-care questionnaires comprised six items, and a point was deducted for each task that the patient could not perform independently. Statistical analysis was performed to determine the association between G3 radiation dermatitis and the lowest self-care behavior scores. Of the 10 patients enrolled, three experienced G3 dermatitis. During CRT, six patients maintained their initial scores and did not develop ≥G3 dermatitis. Meanwhile, three of four patients with decreased scores exhibited ≥G3 dermatitis. The group with ≥G3 dermatitis had significantly lower scores than those with ≤G2 dermatitis, suggesting that the inability of patients to perform self-care routinely may lead to severe acute radiation dermatitis. Further prospective studies are needed to confirm the potential of self-care interventions in preventing severe dermatitis.

UNASSIGNED: The relationship among body mass index (BMI), setup error and radiation pneumonitis is not clearly illustrated.
UNASSIGNED: The present study aimed to investigate the role of BMI in non-small cell lung cancer (NSCLC) patients\' radiation treatment, focusing on its relationship with setup error of patient positioning, the dosimetric parameters of intensity-modulated radiation therapy (IMRT) and the incidence of radiation pneumonitis.
UNASSIGNED: This prospective observational study included 523 cases of NSCLC patients during 2020-2022. Patients were divided into different groups by different BMI. The setup error was obtained by cone beam CT (CBCT) at three positions, lateral (LAT), longitudinal (LNG) and vertical (VRT). IMRT dosimetric parameters of V5, V20, and mean dose were collected.
UNASSIGNED: Patients with BMI ≥28 kg/m2 showed significantly higher absolute values of LAT, LNG and VRT, higher V5, V20, mean dose, as well as higher total incidence of radiation pneumonitis and grade III radiation pneumonitis compared with patients with BMI <24 kg/m2 or 24-28 kg/m2. Spearman\'s analysis demonstrated that the absolute values of LAT, LNG and VRT were positively correlated with BMI, and positive correlation existed among BMI, dosimetric parameters and setup errors. ROC curves showed that LAT in setup errors and V5 in dosimetric parameters had the best diagnostic value for prediction of radiation pneumonitis. Only BMI, LAT, V5 and V20 were the independent risk factors for radiation pneumonitis.
UNASSIGNED: Setup error caused by higher BMI might be associated with the dosimetric parameters, as well as the incidence of radiation pneumonitis in NSCLC patients.

UNASSIGNED: To compare the incidence of grade ≥2 gastrointestinal (GI) or genitourinary (GU) toxicity for patients undergoing 3DRT versus IMRT in the postoperative setting for endometrial cancer.
UNASSIGNED: Eligible patients were post-operatively randomly assigned to one of two parallel groups in a 1:1 ratio, to have their RT delivered using either a 3DRT technique or using IMRT. The prescription dose was 45 Gy in 25 fractions over 5 weeks followed by vaginal vault brachytherapy. Toxicity was graded according to National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) version (v) 3.0. Fisher\'s exact tests were used to test for associations between toxicity and arm. Differences in dosimetric parameters for patients with or without toxicity were tested using Mann-Whitney U-tests.
UNASSIGNED: 84 patients with a median age of 62 were evaluable for primary outcome. The median follow-up was 52 months. 14 (35%) participants from the 3DRT arm and 15 (34%) from the IMRT arm experienced acute grade ≥2 GI toxicity with older patients having a statistically higher risk of grade ≥2 acute GI toxicity. 20 (50%) participants from the 3DRT arm and 25 (57%) from the IMRT arm experienced acute grade ≥2 GI or GU toxicity (p = .662). 12 (30%) patients from the 3DRT arm and 17 (39%) from the IMRT arm experienced acute grade ≥2 GU toxicity (p = .493).
UNASSIGNED: Although IMRT can reduce dose to normal tissue, in this study no benefit in acute GI or GU toxicity outcome was seen.

OBJECTIVE: In this paper, we compare four novel knowledge-based planning (KBP) algorithms using deep learning to predict three-dimensional (3D) dose distributions of head and neck plans using the same patients\' dataset and quantitative assessment metrics.
METHODS: A dataset of 340 oropharyngeal cancer patients treated with intensity-modulated radiation therapy was used in this study, which represents the AAPM OpenKBP - 2020 Grand Challenge dataset. Four 3D convolutional neural network architectures were built. The models were trained on 64% of the data set and validated on 16% for voxel-wise dose predictions: U-Net, attention U-Net, residual U-Net (Res U-Net), and attention Res U-Net. The trained models were then evaluated for their performance on a test data set (20% of the data) by comparing the predicted dose distributions against the ground-truth using dose statistics and dose-volume indices.
RESULTS: The four KBP dose prediction models exhibited promising performance with an averaged mean absolute dose error within the body contour <3 Gy on 68 plans in the test set. The average difference in predicting the D99 index for all targets was 0.92 Gy (p = 0.51) for attention Res U-Net, 0.94 Gy (p = 0.40) for Res U-Net, 2.94 Gy (p = 0.09) for attention U-Net, and 3.51 Gy (p = 0.08) for U-Net. For the OARs, the values for the D m a x ${D_{max}}$ and D m e a n ${D_{mean}}$ indices were 2.72 Gy (p < 0.01) for attention Res U-Net, 2.94 Gy (p < 0.01) for Res U-Net, 1.10 Gy (p < 0.01) for attention U-Net, 0.84 Gy (p < 0.29) for U-Net.
CONCLUSIONS: All models demonstrated almost comparable performance for voxel-wise dose prediction. KBP models that employ 3D U-Net architecture as a base could be deployed for clinical use to improve cancer patient treatment by creating plans with consistent quality and making the radiotherapy workflow more efficient.

UNASSIGNED: This study aims to compare the efficacy and safety of neoadjuvant chemoradiotherapy (nCRT) with different radiotherapy doses (45Gy and 50.4Gy) in patients with locally advanced rectal cancer (LARC).
UNASSIGNED: Herein, 120 patients with LARC were retrospectively enrolled between January 2016 and June 2021. All patients underwent two courses of induction chemotherapy (XELOX), chemoradiotherapy, and total mesorectum excision (TME). A total of 72 patients received a radiotherapy dose of 50.4 Gy, while 48 patients received a dose of 45 Gy. Surgery was then performed within 5-12 weeks following nCRT.
UNASSIGNED: There was no statistically significant difference between the baseline characteristics of the two groups. The rate of good pathological response in the 50.4Gy group was 59.72% (43/72), while in the 45Gy group achieved 64.58% (31/48) (P>0.05). The disease control rate (DCR) in the 50.4Gy group was 88.89% (64/72), compared to 89.58% (43/48) in the 45Gy group (P>0.05). The incidence of adverse reactions for radioactive proctitis, myelosuppression, and intestinal obstruction or perforation differed significantly between the two groups (P<0.05). The anal retention rate in the 50.4Gy group was significantly higher in contrast to the 45Gy group (P<0.05).
UNASSIGNED: Patients receiving a radiotherapy dose of 50.4Gy have a better anal retention rate but also a higher incidence of adverse events such as radioactive proctitis, myelosuppression, and intestinal obstruction or perforation, and a comparable prognosis to patients treated with a radiotherapy dose of 45Gy.

OBJECTIVE: This study introduces innovative strategies, the doublet regimen of concurrent chemoradiotherapy, to ensure longer survival for locoregionally advanced nasopharyngeal carcinoma.
METHODS: We retrospectively reviewed 104 locoregionally advanced nasopharyngeal carcinoma patients who underwent taxane combined platinum-based concurrent chemoradiotherapy in our center between January 2013 and December 2018. All statistical analyses were performed using the Kaplan-Meier method (SPSS 23.0). Different groups were compared with the Wilcoxon rank-sum test.
RESULTS: Ultimately, 104 patients were selected for this study, including 18 and 86 who received either concurrent chemoradiation therapy alone or concurrent chemoradiation therapy plus adjuvant chemotherapy, respectively. The median follow-up time for progression free survival was 53.0 months (IQR 48.5-57.5). The 3-years progression-free survival (PFS), overall survival (OS), local-regional recurrence-free survival (LRRFS) and distant metastasis-free survival (DMFS) rates of the doublet regimen of concurrent chemotherapy for locoregionally advanced nasopharyngeal carcinoma were 85.9%, 96.0%, 96.0% and 90.8%, respectively. Additionally, we analyzed the subgroups and found that the 3-years PFS, OS, LRRFS and DMFS rates for stage III versus stage IVa were 97.8% versus 75.5% (P = 0.000), 100% versus 92.5% (P = 0.004), 100% versus 92.4% (P = 0.015) and 97.8% versus 82.8% (P = 0.002), respectively. During concurrent chemotherapy, acute chemotherapy adverse events of grade 3 or 4 was only 18.3%. Leukopenia was the most common acute chemotherapy adverse event (in 10 patients [9.6%]), followed by neutropenia (in 8 patients [7.6%]).
CONCLUSIONS: The doublet regimen of taxane plus platinum concurrent chemoradiotherapy resulted in improved long-term survival of locoregionally advanced nasopharyngeal carcinoma patients, especially for local control rate and warrants further prospective evaluation.