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To accurately capture crack trajectory and failure morphology with continuum mesoscopic model-based methods in three-dimensional space, conventional global uniform refinement schemes may incur significant computational cost. This paper first presents a three-dimensional structured mesh refinement strategy to achieve the hierarchical discretization for the focused region. To deal with the mismatching problem caused by different-sized meshes, a coupling interface technique based on the discontinuous Galerkin framework is proposed. The validity and advantages of the present strategy are first verified by a benchmark example for elastic analysis. By strongly collaborating with the statistical meso-damage smear method, we further simulate the spatial crack growth (including a through-thickness crack, an embedded crack, and a surface crack) and the local failure process of a D-shaped tunnel. Great agreements between the simulation results and the available experiment or numerical reference results demonstrate that the present method can effectively simulate the rock fracturing process as well as save considerable computational time and memory storage. Highlights: A three-dimensional structured mesh refinement strategy is presented for the geometric and scale restrictions of rock meso-fracturing simulations. An effective coupling interface technique is introduced to accurately capture the interface effects and couple different-sized meshes. Different crack configurations, including a through-thickness crack, an embedded crack, and a surface crack are simulated. The present method can achieve an ideal trade-off between accuracy and computing effort. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to analyse the independent prognostic significance of perineural invasion (PNI) on local recurrence (LR) in patients with oral squamous cell carcinoma (OSCC) managed primarily with surgery. Subjects and Methods: Clinical and histopathological data of 195 patients with OSCC were analysed retrospectively to identify risk factors associated with PNI and to evaluate its significant correlation with local recurrence, overall survival (OS) and recurrence free survival (RFS). Results: Patients were followed for a mean period of 39.5 ± 1.376 months and median 35 months. PNI was found in 57 patients (29.2%). PNI correlated with tongue subsite (p = 0.001), nodal metastasis (p < 0.000), depth of invasion (DOI) (p = 0.002), stage (p = 0.013) and adjuvant therapy (p < 0.001). Mean time to recurrence with PNI was significantly shorter (p = 0.002).Multivariate analysis did not establish significant relationship between PNI and LR. Kaplan–Meier curve did not show statistical significance with OS (p = 0.085) or RFS (p = 0.110). Conclusion: PNI remains an aggressive factor for nodal metastasis mandating neck management for regional control. Though PNI showed no statistical significance with LR, time to recurrence in PNI positive patients were significantly shorter. Hence, close follow-up regimen becomes necessary. [ABSTRACT FROM AUTHOR]

Introduction: This study compares four management paradigms for large brain metastasis (LMB): fractionated SRS (FSRS), staged SRS (SSRS), resection and postoperative-FSRS (postop-FSRS) or preoperative-SRS (preop-SRS). Methods: Patients with LBM (≥ 2 cm) between July 2017 and January 2022 at a single tertiary institution were evaluated. Primary endpoints were local failure (LF), radiation necrosis (RN), leptomeningeal disease (LMD), a composite of these variables, and distant intracranial failure (DIF). Gray's test compared cumulative incidence, treating death as a competing risk with a random survival forests (RSF) machine-learning model also used to evaluate the data. Results: 183 patients were treated to 234 LBMs: 31.6% for postop-FSRS, 28.2% for SSRS, 20.1% for FSRS, and 20.1% for preop-SRS. The overall 1-year composite endpoint rates were comparable (21 vs 20%) between nonoperative and operative strategies, but 1-year RN rate was 8 vs 4% (p = 0.012), 1-year overall survival (OS) was 48 vs. 69% (p = 0.001), and 1-year LMD rate was 5 vs 10% (p = 0.052). There were differences in the 1-year RN rates (7% FSRS, 3% postop-FSRS, 5% preop-SRS, 10% SSRS, p = 0.037). With RSF analysis, the out-of-bag error rate for the composite endpoint was 47%, with identified top-risk factors including widespread extracranial disease, > 5 total lesions, and breast cancer histology. Conclusion: This is the first study to conduct a head-to-head retrospective comparison of four SRS methods, addressing the lack of randomized data in LBM literature amongst treatment paradigms. Despite patient characteristic trends, no significant differences were found in LF, composite endpoint, and DIF rates between non-operative and operative approaches. [ABSTRACT FROM AUTHOR]

Purpose: Local recurrences after radical prostatectomy (RP) and postoperative radiotherapy (RT) are challenging for salvage treatment. Retrospective analysis of own experiences with salvage re-irradiation was performed. Methods: The study included all consecutive patients treated with salvage stereotactic body radiotherapy (sSBRT) for prostate bed recurrence following RP and postoperative RT at a single tertiary center between 2014 and 2021. Treatment toxicity defined as the occurrence of CTCAE grade ≥ 2 genito-urinary (GU) or gastro-intestinal (GI) adverse events (AEs) was assessed. A PSA response, biochemical control (BC) and overall survival (OS) were also evaluated. Results: The study group included 32 patients with a median age of 68 years and a median follow-up of 41 months, treated with CyberKnife (53%) or Linac (47%) sSBRT. Total dose of 33.75–36.25 Gy in five fractions (72%) was applied in the majority of them. Approximately 19% patients reported grade ≥ 2 GU AEs both at baseline and at three months, and grade ≥ 2 GI toxicity increased from 0% at baseline to 6% at three months after sSBRT. There was some clinically relevant increase in late toxicity with 31% patients reporting late ≥ 2 GU, and 12.5% late ≥ 2 GI AEs. Two grade 3 AEs were recorded: recto-urinary fistulas. The majority of patients showed a PSA response (91% at one year post-sSBRT). The 3‑year BC was 40% and 3‑year OS was 87%. Conclusions: Manageable toxicity profile and satisfactory biochemical response suggest that SBRT in patients with local recurrence following RP and postoperative RT might be a salvage option for selected patients. [ABSTRACT FROM AUTHOR]

Nasopharyngeal carcinoma (NPC) is a radiotherapy-sensitive tumor, but local recurrence still exists in part of the patients after receiving radiotherapy. The location of local recurrence of NPC is usually "in-field" and cases of parotid and mastoid recurrences have been reported. We report a fifty-nine-year-old female patient who presented with maxillary sinus anterior wall recurrence seven months after intensitymodulated radiotherapy (IMRT). Magnetic resonance imaging (MRI) showed a soft tissue mass in the anterior wall of the right maxillary sinus and the recurrence of NPC was confirmed by histopathology after biopsy. To date, the patient is alive with disease without distant metastasis. To our knowledge, this is the first report of maxillary Sinus anterior wall recurrence after IMRT for NPC. [ABSTRACT FROM AUTHOR]

The latticed dunes in the Tengger Desert are widely distributed, and the sand-blocking fence placed here are highly susceptible to local failure due to complex wind-sand activities, posing a serious threat to the safe operation of the highway. To explore the local failure mechanism of sand-blocking fence in the latticed dune area, the local failure of sand-blocking fence in the latticed dune areas along the Wuhai-Maqin Highway in China was observed. Taking the first main ridge of the latticed dune as the placement location, the structure of the wind-sand flow field of sand-blocking fence placed at top, the bottom and the middle of windward slope was analyzed by Computational Fluid Dynamics (CFD). The results show that when placed at top of the first main ridge, the wind speed near the sand-blocking fence is the highest, up to 15.23 m/s. Therefore, the wind load strength on the sand barrier is correspondingly larger, up to 232.61 N·m−2. As the strength of material continues to decrease, the nylon net is prone to breakage. The roots of the angle steel posts are susceptible to hollowing by vortex action, which can cause sand-blocking fence to fall over in strong wind conditions. When placed at the bottom of windward slope, wind speed drop near sand-blocking fence is greatest, with the decrease of 12.48–14.32 m/s compared to the original wind speed. This is highly likely to lead to large-scale deposition of sand particles and burial of the sand-blocking fence. When placed in the middle of windward slope, sand-blocking fence is subjected to less wind load strength (168.61N·m−2) and sand particles are mostly deposited at the bottom of windward slope, with only a small amount of sand accumulating at the root of sand-blocking fence. Based on field observations and numerical modelling results, when the sand-blocking fence is placed in latticed dune area, it should be placed in the middle of the windward slope of the first main ridge as a matter of priority. Besides the sand-blocking fence should be placed at the top of the first main ridge, and sand fixing measures should be added. [ABSTRACT FROM AUTHOR]

Pultruded GFRP (glass fiber-reinforced polymer) materials are widely used in structural engineering because of their lightweight, corrosion immunity, and electromagnetic transparency. However, the design of load-bearing components facing substantial compressive stresses, e.g., columns, must be more stringent than steel structures due to excessive deformability, material heterogeneity, and vulnerability to stress concentration. This manuscript investigates the failure performance of locally produced GFRP materials, focusing on the material heterogeneity effect on the mechanical resistance of a support joint of a pultruded tubular GFRP column. This experimental campaign employs relatively short rectangular profile fragments to isolate the support behavior and verify a simplified numerical finite element model, which neglects the nonlinearity of GFRP material. This work determines the material failure mechanisms behind the mechanical performance of pultruded profiles subjected to longitudinal compression for various column lengths. [ABSTRACT FROM AUTHOR]

Objective: To develop a Multi-Feature-Combined (MFC) model for proof-ofconcept in predicting local failure (LR) in NSCLC patients after surgery or SBRT using pre-treatment CT images. This MFC model combines handcrafted radiomic features, deep radiomic features, and patient demographic information in an integrated machine learning workflow. Methods: The MFC model comprised three key steps. (1) Extraction of 92 handcrafted radiomic features from the GTV segmented on pre-treatment CT images. (2) Extraction of 512 deep radiomic features from pre-trained U-Net encoder. (3) The extracted handcrafted radiomic features, deep radiomic features, along with 4 patient demographic information (i.e., gender, age, tumor volume, and Charlson comorbidity index), were concatenated as a multi-dimensional input to the classifiers for LR prediction. Two NSCLC patient cohorts from our institution were investigated: (1) the surgery cohort includes 83 patients with segmentectomy or wedge resection (7 LR), and (2) the SBRT cohort includes 84 patients with lung SBRT (9 LR). The MFC model was developed and evaluated independently for both cohorts, and was subsequently compared against the prediction models based on only handcrafted radiomic features (R models), patient demographic information (PI models), and deep learning modeling (DL models). ROC with AUC was adopted to evaluate model performance with leave-one-out cross-validation (LOOCV) and 100-fold Monte Carlo random validation (MCRV). The t-test was performed to identify the statistically significant differences. Results: In LOOCV, the AUC range (surgery/SBRT) of the MFC model was 0.858-0.895/0.868-0.913, which was higher than the three other models: 0.356-0.480/0.322-0.650 for PI models, 0.559-0.618/0.639-0.682 for R models, and 0.809/0.843 for DL models. In 100-fold MCRV, the MFC model again showed the highest AUC results (surgery/SBRT): 0.742-0.825/0.888-0.920, which were significantly higher than PI models: 0.464-0.564/0.538-0.628, R models: 0.557-0.652/0.551-0.732, and DL models: 0.702/0.791. Conclusion: We successfully developed an MFC model that combines feature information from multiple sources for proof-of-concept prediction of LR in patients with surgical and SBRT early-stage NSCLC. Initial results suggested that incorporating pre-treatment patient information from multiple sources improves the ability to predict the risk of local failure. [ABSTRACT FROM AUTHOR]

Tensile tests were conducted for notched round-bar specimens to acquire the limit conditions of local failure, which is ductile failure after large local deformation for three types of steel, SGV480, SPV490 and SGV410, for nuclear containment structures. The notch deformation was monitored using a profile projector. The notch’s cross-section radius and the curvature radius of the notched profile were continuously measured by image analysis in the tensile test. From those measurements, the stress and strain at the notch’s cross-section center were determined by Bridgman’s approximate solution and the elastoplastic FEM analysis. The true stress-true strain curve for the elastoplastic FEM was identified a priori by an optimization program that searches for the good curve in the exponential form applicable to large strain regions. No cracks were observed at the notch bottom surface in all specimens until the final rupture. The failure at the notch’s cross-section center was detected from the inflection point of the load-displacement curve. The limit strain diagrams were compared with those of ASME Sec. VIII-2 and its conservatism were discussed. Further, small-size notched round-bar specimens were sampled from the weld joints of SGV480 and SPV490 to determine the limit strain diagrams and true stress-true strain curves of the base metal, HAZ, and weld metal. The limit strain diagrams at each material of the weld joints were as high as or higher than the base metal, except for the weld metal of SPV490. The authors discussed the optical micrographs for fracture surfaces of specimens, the fracture morphology of weld joints, and the modified expression of a limit failure stress index regarded as the stress indication of the limit strain diagram in the high-stress triaxiality region.

Radiotherapy (RT) or chemoradiotherapy (CRT) are frequently selected as treatments for esophageal squamous cell carcinoma (ESCC). However, salvage treatment remains challenging when endoscopic resection is not indicated for residual or recurrent ESCC following RT or CRT. Recently, owing to the emergence of second-generation photodynamic therapy (PDT) using talaporfin sodium, PDT can be performed with less phototoxicity and therefore has regained popularity in the treatment of ESCC. In this study, the effectiveness and safety of second-generation PDT in patients with residual or recurrent ESCC following RT or CRT were examined. Local complete response (L-CR) rates, procedure-related adverse events, and prognosis were evaluated. In 12 patients with 20 ESCC lesions, the L-CR rates were 95.0%. Perforation, postoperative bleeding, and photosensitivity were not observed. Esophageal stricture following PDT developed in one patient, but this could be addressed using balloon dilation. During a median follow-up period of 12 (range, 3–42) months, the 3-year cause-specific survival rate was 85.7%. Even in patients with a Charlson comorbidity index score ≥ 3, the 2-year overall survival rates were 100%. In conclusion, PDT was an efficacious and a safe salvage treatment in patients with local residual or recurrent ESCC following RT or CRT. [ABSTRACT FROM AUTHOR]

BackgroundThe importance of local failure (LF) after treatment of high-grade prostate cancer (PCa) with definitive radiotherapy (RT) remains unknown.ObjectiveTo evaluate the clinical implications of LF after definitive RT.Design, setting, and participantsIndividual patient data meta-analysis of 992 patients (593 Gleason grade group [GG] 4 and 399 GG 5) enrolled in six randomized clinical trials.Outcome measurements and statistical analysisMultivariable Cox proportional hazard models were developed to evaluate the relationship between overall survival (OS), PCa-specific survival (PCSS), and distant metastasis (DM)-free survival (DMFS) and LF as a time-dependent covariate. Markov proportional hazard models were developed to evaluate the impact of specific transitions between disease states on these endpoints.Results and limitationsMedian follow-up was 6.4 yr overall and 7.2 yr for surviving patients. LF was significantly associated with OS (hazard ratio [HR] 1.70 [95% confidence interval {CI} 1.37-2.10]), PCSS (3.10 [95% CI 2.33-4.12]), and DMFS (HR 1.92 [95% CI 1.54-2.39]), p

Many previous accidents have indicated that a small local failure in a shield tunnel might induce progressive failure of the tunnel structure, and the underlying mechanisms are still unclear. Before the study of the progressive failure of shield tunnels, the response of the tunnel structure adjacent to the local failure zone should be first clarified because it could help explain how progressive failure is triggered by a small local failure. In this article, physical model tests were reviewed briefly and reproduced by numerical modelling based on the coupled Eulerian–Lagrangian (CEL) method. Good agreement was achieved between the results of the numerical models and physical model tests, which showed the reliability of the numerical models. Then, a full-scale simulation was conducted to quantitatively investigate the impact of local failure on adjacent structures (segments and bolts) in practical engineering. It was shown that the torsions and shear forces of the adjacent segments would increase and exceed the bearing capacities. Parametric analyses were also performed to investigate the effect of the assembly method, cover depth and number of initial dismantled segments (IDSs) on the safety of adjacent tunnel structures. The results indicated that 1) the impact of the local failure in a straight-jointed tunnel was smaller than that in a stagger-jointed tunnel; 2) when the cover depth of the tunnel was greater, the number of unsafe structures and the maximum of state evaluation factor (SEF) were also greater; and 3) when the number of IDSs was greater, the impact of the local failure was much larger. [ABSTRACT FROM AUTHOR]

A series of tensile tests were conducted for notched plate specimens whose shapes are similar to the pressure shell to clarify the local failure characteristics for the steel nuclear containment. The specimens included the full or partial-width notched plate specimens of 10 mm thickness, and full-width notched thick plate specimens of 34 mm thickness the same as the actual pressure shell. In the full-width notched plate specimens with a small curvature notch, the cracking occurred on the notch bottom, and the crack propagated and finally ruptured. The plate specimens with a large curvature notch failed in shear suddenly without notch bottom cracking. Those failure modes were very unlike notched round-bar specimens, in which failure always starts at the notch section center. In the case of partial-width notch plate specimens, the notch bottom cracking also occurred for a small curvature notch, and the notch section failure happened before the specimen’s rupture for a large curvature notch. The limit strain diagrams were 40% to 50% lower than those of the notched round-bar specimens. The limit failure stress indexes, which correspond to the stress indications for the limit strain diagrams, could be applied to the shear failure of notched plate specimens. The indexes of the notched plate specimens were approximately 10% lower than those of the round-bar specimens. The crack initiation points for small curvature notch specimens were concentrated in the range of stress triaxiality 0.6 and equivalent plastic strain 0.5 to 0.8. In the full-width notched thick plate specimens, notch bottom cracking occurred for all specimens, and the cracking conditions were almost the same as the full and partial notched plate specimens. However, the maximum nominal stress exceeded 2/3 of the design tensile strength, and it was concluded that local failure occurs at more than twice the design pressure.

Pultruded GFRP (glass fiber-reinforced polymer) materials are widely used in structural engineering because of their lightweight, corrosion immunity, and electromagnetic transparency. However, the design of load-bearing components facing substantial compressive stresses, e.g., columns, must be more stringent than steel structures due to excessive deformability, material heterogeneity, and vulnerability to stress concentration. This manuscript investigates the failure performance of locally produced GFRP materials, focusing on the material heterogeneity effect on the mechanical resistance of a support joint of a pultruded tubular GFRP column. This experimental campaign employs relatively short rectangular profile fragments to isolate the support behavior and verify a simplified numerical finite element model, which neglects the nonlinearity of GFRP material. This work determines the material failure mechanisms behind the mechanical performance of pultruded profiles subjected to longitudinal compression for various column lengths.

Background: To assess the pattern of response of presumed local lesions at dynamic contrast enhancement magnetic resonance imaging (DCE-MRI) after salvage radiotherapy (sRT). Methods: This is a prospective study conducted at a single Institution accruing patients with one or more local failures at DCE-MRI after radical prostatectomy between August 2017 and June 2020. Patients underwent exclusive sRT delivering 66–69 Gy and 73.5 Gy in 30 fractions to the whole prostatic fossa and to the local failure(s) seen at DCE-MRI, respectively.Patients were offered DCE-MRI at 3 months intervals after sRT until complete disappearance (CR) of the lesion(s) or up to a maximum of 4 revaluations. Results: 62 patients with 72 nodules were enrolled. All patients underwent the 1st revaluation, and 33 patients (53.2%) showed a CR. The median time to CR was 4.7 months. Four patients did not undergo further testing before achieving a CR and even considering these patients as no responses, the vast majority (87.1%, 95%CI: 78.5–94.4%) of lesions would have completely disappeared by 12 months from the end of sRT.The volume of the lesion at pre-sRT DCE-MRI was an independent predictor of CR at the 1st revaluation (OR: 0.076, 95%CI: 0.009–0.667; p = 0.020) along with time elapsed from sRT (OR: 3.399, 95% CI: 1.156–9.993, p = 0.026). Conclusions: The present study documents the complete disappearance of the vast majority of local lesions after dose-escalated sRT though this requires several months after sRT; timing of CR is at least in part predictable based on the volume of the lesion.Trial registration: Clinicaltrials.gov NCT04703543, registered July 15 2020, retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT04703543.

Simple Summary: The role of restaging before salvage radiotherapy (sRT) for prostate cancer is still controversial. The aim of the present retrospective study was to investigate the predictive value of dynamic contrast-enhanced-magnetic resonance imaging (DCE-MRI) findings, including the volume and the subsite of the presumed local failure. We found that DCE-MRI at restaging for biochemical failure after radical prostatectomy seems to provide both predictive and therapeutic information. Patients with small lesions at the vesico-urethral anastomosis have an excellent prognosis after sRT. Background: To investigate the predictive role of dynamic contrast-enhanced-magnetic resonance imaging (DCE-MRI) findings before salvage radiotherapy after radical prostatectomy (RP). Methods: This retrospective study selected patients with biochemical failure (BF) after RP restaged with DCE-MRI. Patients underwent sRT in 30 fractions delivering 66–69 Gy and 73.5 Gy to the prostatic fossa and to the local failure as per DCE-MRI, respectively. Pelvic nodes were treated to 54 Gy in selected patients. The endpoint was BF after sRT. Results: In total, 236 patients were analyzed and 146 (61.9%) had presumed local failure at DCE-MRI: 54.8%, 23.8% and 21.4% were found at the vesico-urethral anastomosis (VUA), the bladder neck and the retro-vesical space, respectively. The presence of a local failure at DCE-MRI halved the risk of BF; VUA-only location and lesion volume were independently correlated with survival without evidence of biochemical failure (bNED) at multivariable analysis. For patients with VUA-only disease up to 0.4 cc, the 4-year-bNED was 94.6% (95%CI: 80.2–98.6%) as opposed to 80.9% (95%CI: 71.6–87.4%) and 73.7% (95%CI: 63.1–81.8%) for other lesions and no macrodisease, respectively. Conclusions: DCE-MRI at restaging for BF after RP provides predictive and therapeutic information. Patients with small lesions at the VUA have an excellent prognosis after sRT. [ABSTRACT FROM AUTHOR]

Excavation collapses of brace-row pile supporting system occur frequently, aiming at the structural safety problems caused by the brace local failure, using the method of indoor model test and numerical simulation, the influences on excavation was revealed by comparing the changes of excavation deformation and structural internal force before and after component failure. The results show that the wall deformation caused by brace failure is most obvious in the middle and lower parts above the excavation surface. The impact of load on surface settlement is greater than brace failure. Compared with the upper brace, the lower brace failure is more unfavorable to the supporting system. After the brace failure, the wall deformation diffused around the position to the vicinity of the adjacent brace, which will limit the further diffusion of this displacement. After the failure of the lowest brace, the impact on the intact brace in the vertical direction is greater than that on the horizontal direction. With the decrease of the depth of the failed brace, the impact in the vertical direction gradually decreases and the impact in the horizontal direction gradually increases. After the local failure of brace, the load transfer has an obviously nearby phenomenon, and the load transfer coefficient increases with the increase of the failed brace number. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to identify whether the platelet-to-lymphocyte ratio (PLR) correlated with the prognosis of patients with locally advanced hypopharyngeal squamous cell carcinoma (LA-HPSCC) undergoing radiotherapy combined with chemotherapy. Methods: This study enrolled 103 patients diagnosed with LA-HPSCC and treated with radiotherapy combined with chemotherapy between 2008 and 2021. The optimal PLR cut-off value was chosen from the receiver operating characteristic (ROC) curve analysis. According to the cut-off value of PLR, patients were divided into two groups: a low PLR group (< 133.06) and a high PLR group (≥ 133.06). Propensity score matching (PSM) was used to balance the confounding factors between the two PLR groups. Univariate and multivariate Cox proportional hazard regression models, the Kaplan–Meier curve by the log-rank test, and univariate and multivariate Fine-Gray competing risk models were all used for assessment. Results: After PSM, 27 pairs were left, and the high PLR group correlated with higher local failure (sHR 6.91, 95% CI 2.14–22.35, p = 0.001) in the multivariate Fine-Gray competing risk model. Moreover, the low PLR group had a significantly longer 3-year progression-free survival (43.7% vs. 29.2%, p = 0.038) and overall survival (55.1% vs. 32.1%, p = 0.034) than the high PLR group had. Multivariate Cox analysis showed that a low PLR was an independent protective factor for PFS (HR 0.43, 95% CI 0.21–0.92, p = 0.019) and OS (HR 0.46, 95% CI 0.22–0.96, p = 0.039) in patients with LA-HPSCC. Conclusion: Pretherapy PLR might be a factor in predicting the risk of local failure and survival in LA-HPSCC patients undergoing radiotherapy combined with chemotherapy. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to evaluate the efficacy of radiation therapy (RT) for recurrent or residual pituitary macroadenoma (PMA) invading extrasellar regions. Materials and Methods: Patients from 2000 to 2020 who received RT with conventional fractionation for recurrent or residual PMA were included. The patients were divided according to the type of tumor [functioning (fx) or non-fx] and the aim of RT (salvage RT alone, immediate postoperative RT, delayed postoperative RT). Local and biochemical failure-free rates (FFR) were calculated using the Kaplan-Meier method. Results: With a median follow up of 82 months (IQR; 42-132 months), 36 patients treated with conventional RT (total 45-54 Gy in 1.8 or 2 Gy per fraction) for recurrent or residual PMA were analyzed. The 10-year local FFRs after RT for non-fx and fx tumor were 100% and 74.4%, respectively (p=0.047). In the immediate postoperative RT group, the 10-year local FFR was 100%, which was higher than the 90% FFR for salvage RT alone or 80% FFR for the delayed postoperative RT group (overall p=0.043, immediate vs. salvage; p=0.312, immediate vs. delayed; p=0.072). The local FFR was compared according to size of tumor with a cut-off value of 4 cm, and there was no significant difference (10-year local FFR 100% vs. 84.7% for >4 cm vs. <4 cm, p=0.320). The extents of extrasellar region invasion were not predictive of local failure after RT. We found no grade =3 acute toxicities or newly developed visual impairments as a late toxicity of RT. Conclusion: Conventional RT is safe and effective for the local control of recurrent or residual PMA. Our data suggest that immediate postoperative RT can be beneficial in recurrent or residual PMA, although further studies to evaluate risk factors of treatment failure in terms of treatment and disease characteristics are required. [ABSTRACT FROM AUTHOR]

The benefit of breast magnetic resonance imaging (MRI) in breast-conserving surgery (BCS) is unclear. Our study compared breast cancer patients with and without preoperative breast MRI and their long-term oncologic outcomes are reported. A total of 1378 BCS cases with early breast cancer between 1996 and 2017 were reviewed. Patients with carcinoma in situ or neoadjuvant treatment or having breast MRI after tumor excision were excluded. Of 1378 patients, 270 (19.5%) had preoperative MRI. There were no significant differences regarding T and N stage and molecular subtypes between the groups. Surgical margins were significantly wider in the breast MRI group. Five-year overall survival (OS) was 96.9% in the MRI group and 94.3% in the control group, and this difference was not significant (p=0.11). Five-year local-regional recurrence-free survival (LRFS) was not significantly different either (98.8% and 96.5%, respectively, p=0.41). When analyses were repeated only for patients with hormone receptor-negative or triple-negative breast cancer, there was still no significant difference in OS, LRFS, or disease-free survival. In conclusion, MRI does not seem necessary in all patients undergoing BCS. New prospective randomized controlled trials are needed to determine appropriate use of preoperative MRI and its effects on oncologic outcomes in early breast cancer patients.

We provide the strongest evidence to date that local failure is an independent prognosticator of outcomes in high- and intermediate-risk prostate cancer patients treated with definitive radiation therapy. Distant metastasis predominantly develops from a clinical relapse-free state; however, a second wave of distant metastasis occurs subsequent to local failure, albeit less commonly. The prognostic importance of local failure after definitive radiotherapy (RT) in National Comprehensive Cancer Network intermediate- and high-risk prostate cancer (PCa) patients remains unclear. To evaluate the prognostic impact of local failure and the kinetics of distant metastasis following RT. A pooled analysis was performed on individual patient data of 12 533 PCa (6288 high-risk and 6245 intermediate-risk) patients enrolled in 18 randomized trials (conducted between 1985 and 2015) within the Meta-analysis of Randomized Trials in Cancer of the Prostate Consortium. Multivariable Cox proportional hazard (PH) models were developed to evaluate the relationship between overall survival (OS), PCa-specific survival (PCSS), distant metastasis-free survival (DMFS), and local failure as a time-dependent covariate. Markov PH models were developed to evaluate the impact of specific transition states. The median follow-up was 11 yr. There were 795 (13%) local failure events and 1288 (21%) distant metastases for high-risk patients and 449 (7.2%) and 451 (7.2%) for intermediate-risk patients, respectively. For both groups, 81% of distant metastases developed from a clinically relapse-free state (cRF state). Local failure was significantly associated with OS (hazard ratio [HR] 1.17, 95% confidence interval [CI] 1.06–1.30), PCSS (HR 2.02, 95% CI 1.75–2.33), and DMFS (HR 1.94, 95% CI 1.75–2.15, p < 0.01 for all) in high-risk patients. Local failure was also significantly associated with DMFS (HR 1.57, 95% CI 1.36–1.81) but not with OS in intermediate-risk patients. Patients without local failure had a significantly lower HR of transitioning to a PCa-specific death state than those who had local failure (HR 0.32, 95% CI 0.21–0.50, p < 0.001). At later time points, more distant metastases emerged after a local failure event for both groups. Local failure is an independent prognosticator of OS, PCSS, and DMFS in high-risk and of DMFS in intermediate-risk PCa. Distant metastasis predominantly developed from the cRF state, underscoring the importance of addressing occult microscopic disease. However a "second wave" of distant metastases occurs subsequent to local failure events, and optimization of local control may reduce the risk of distant metastasis. Among men receiving definitive radiation therapy for high- and intermediate-risk prostate cancer, about 10% experience local recurrence, and they are at significantly increased risks of further disease progression. About 80% of patients who develop distant metastasis do not have a detectable local recurrence preceding it. [ABSTRACT FROM AUTHOR]

Verrucous carcinoma (VC) is a locally invasive uncommon histopathological variant of oral squamous cell cancer. There is paucity of literature regarding control rates in these cases. We intend to report the outcomes in terms of administered treatment and control rates. 28 patients of oral cavity verrucous carcinomas treated at our institute from March 2014 to December 2018 were reviewed retrospectively. Demographic profile, histopathological features and clinical outcomes were analyzed. Statistical analysis was performed with SPSS for Mac (version 23.0). Median age was 54 years (range 31–75) with M:F ratio of 25:3. Buccal mucosa was the most common site. All patients underwent surgical resection except one. Of these, 24 had neck dissection; 12 had supra-omohyoid neck dissection, eleven had modified neck dissection and one patient underwent radical neck dissection. Three patients had their histology upgraded to squamous cell carcinomas in the post-operative histopathology. The post-operative staging was as follows: 21% stage I and 35% stage II. One patient opted for non-surgical approach and received radical concurrent chemoradiotherapy. Median follow up was 12 months (range 6–36). Two patients had local failures and one had a regional failure. No distant metastasis was found. There was one death. 14-Months survival rate was 92%. Estimated 18 month loco-regional control rate was 92%. Curative surgical resection remains the cornerstone for VC of oral cavity. Any change of histopathology post-operatively to squamous cell carcinoma is a poor prognostic sign and needs appropriate adjuvant treatment. [ABSTRACT FROM AUTHOR]

Local failure of non-small cell lung cancer (NSCLC) treated with stereotactic body radiation therapy (SBRT) often occurs within 2 years and delayed local failure is uncommon. In the present study, features of late local failure (LLF; >2 years after SBRT) after SBRT were investigated and compared with those of early local failure (ELF; ≤2 years after SBRT) to explore whether these two local recurrence features have different prognostic implications. Patients who underwent SBRT for stage I-IIA NSCLC between July 2006 and March 2014 were retrospectively reviewed. Overall, 173 patients underwent SBRT for NSCLC. The median follow-up times after SBRT were 50 and 31 months for survival and computed tomography (CT) follow-up, respectively. LLF and ELF occurred in 7 and 13 patients, respectively. The median times to LLF and ELF were 42 months (range, 31-61 months) and 13 months (range, 4-16 months), respectively. Local-only failure occurred in 14% (1/7) of LLF cases and 77% (10/13) of ELF cases, which was significantly different (Fisher's exact test, P=0.02). Curative-intent salvage treatment was impossible in all of the LLF cases and 69% (9/13) of the ELF cases, which was significantly different (Fisher's exact test, P<0.01). The median survival times after local failure were 9 and 25 months for patients with LLF and ELF, respectively. Additionally, the 1-year overall survival rates after local failure were 29 and 83% in the LLF and ELF groups, respectively, which was significantly different (log-rank test, P<0.01 at 1-year). In summary, the prognosis after LLF was significantly unfavorable compared with after ELF. Curative-intent salvage treatment is often difficult for LLF due to metastases. Therefore, it seems reasonable to decrease the frequency of follow-up CT for detecting tumor recurrence after the first 2 years post-SBRT., Competing Interests: The authors declare that they have no competing interests., (Copyright: © 2024 Makita et al.)

Surgery is standard of care for oral cavity cancer (OCC). We provide a single-institution experience using definitive radiotherapy (RT) with or without concurrent systemic therapy for primary unresectable OCC.

To determine the factors associated with a positive post-treatment prostate biopsy (PB) and the effects of local failure on biochemical control and cause-specific survival (CSS) in men receiving prostate brachytherapy. Of 545 men with post-implant PB, 484 were routine (median 24 months) while 61 (median 55 months) were for cause. 114 had a repeat PB for rising PSA. Initial mean PSA was 10.5 ng/ml (±13.9) while 244 (44.8%), 202 (37.1%) and 99 (18.2%) had low, intermediate or high-risk disease. Treatments were implant only in 287 (52.7%), and implant with androgen deprivation therapy (ADT) ± external beam in 258. Radiation doses were converted to the biologically equivalent dose (BED). Final biopsy results were the last biopsy performed on that patient. Associations for the first and final biopsies with PSA, clinical stage (CS), Gleason grade group, time on hormone therapy (ADT) and BED were determined by ANOVA, chi-square and binary linear regression. Freedom from Phoenix failure (FFPF) and cause-specific survival were estimated by Kaplan Meier method and Cox proportions hazards. After a median of 11.4 years the first and final biopsy were positive in 10.8% and 8.8%, respectively. Significant linear regression associations with first positive PB were ADT (p = 0.005), CS (p = 0.044) and BED (p = 0.030) while only BED (p < 0.001) was significant for the final PB. Positive biopsy occurred in 21/112 (18.8%), 16/230 (7.0%) and 3/182 (1.6%) for BED ≤150, >150–200 and >200 Gy (p < 0.001), and in 29/261 (11.1%) for BED (median) ≤185 Gy vs. 5/263 (1.9%) for > 185 Gy (OR 4.2, p < 0.001). 15-year FFPF was 75.6 vs. 17.5% and cause-specific survival was 94.2 vs. 75.5% for negative vs. positive biopsy. Higher radiation doses are associated with 1.9% late local failure following prostate brachytherapy. A negative post-implant PB is associated with superior FFPF and decreased prostate cancer mortality. [ABSTRACT FROM AUTHOR]

The design philosophy of fail-safe structures was first proposed in the aerospace industry to provide redundant load paths as back-ups when local damage happens. Most fail-safe topology optimization methods paid more attention to minimizing compliance of the worst failure case. However, the stress concentration due to local failure may lead to secondary damage and further destroy the structure. In the current work, the von Mises stress of damaged structures is considered as the optimization objective, to alleviate the stress concentration caused by possible local failures. Two sorts of topology optimization objectives are investigated: (1) the worst-case formulation; (2) the mean-performance formulation. To avoid the ‘singularity’ problem, the stress is penalized through the RAMP interpolation scheme. The Kreisselmeier-Steinhauser (KS) aggregation function is used to approximate the global stress level. Concerning the highly nonlinear stress behavior, the Method of Moving Asymptotes (MMA) solver is adopted. Finally, the benefits and drawbacks of these two objective functions are systematically compared and discussed through several numerical examples. [ABSTRACT FROM AUTHOR]

The analytical method for slope stability analysis requires a collapse mechanism in advance. The collapse mechanism for a multi-staged slope is generally assumed to be overall failure, whereas this kind of slope may suffer from local failure. However, a local failure is rarely reported in the previous research for multi-staged slopes, which may result in an overestimate for slope stability. To this end, local failure is incorporated into the collapse mechanism for the first time, so as to develop a complete approach to assess the stability of multi-stage slopes. The modified pseudo-dynamic method is conducted to properly account for seismic effects. Thanks to the limit analysis method and strength reduction technique, the safety factor of a multi-stage slope is obtained. The result obtained by the presented approach shows a good agreement with that of previous literature and numerical calculations. The collapse mechanism of multi-stage slopes is studied, and the safety factor is presented schematically for a wide range of parameters. The results show that the local failure for a multi-stage slope often manifests under the intense seismic effects.

Radiotherapy (RT) or chemoradiotherapy (CRT) are frequently selected as treatments for esophageal squamous cell carcinoma (ESCC). However, salvage treatment remains challenging when endoscopic resection is not indicated for residual or recurrent ESCC following RT or CRT. Recently, owing to the emergence of second-generation photodynamic therapy (PDT) using talaporfin sodium, PDT can be performed with less phototoxicity and therefore has regained popularity in the treatment of ESCC. In this study, the effectiveness and safety of second-generation PDT in patients with residual or recurrent ESCC following RT or CRT were examined. Local complete response (L-CR) rates, procedure-related adverse events, and prognosis were evaluated. In 12 patients with 20 ESCC lesions, the L-CR rates were 95.0%. Perforation, postoperative bleeding, and photosensitivity were not observed. Esophageal stricture following PDT developed in one patient, but this could be addressed using balloon dilation. During a median follow-up period of 12 (range, 3–42) months, the 3-year cause-specific survival rate was 85.7%. Even in patients with a Charlson comorbidity index score ≥ 3, the 2-year overall survival rates were 100%. In conclusion, PDT was an efficacious and a safe salvage treatment in patients with local residual or recurrent ESCC following RT or CRT.

The construction and maintenance of a railway track is an expensive process. Therefore, nowadays, except for advanced countries, considerable attention must be paid to apply the optimal maintenance of railway lines. In Hungary, until 2020 nearly 11% of railway tracks were renewed and rehabilitated from EU support, which means millions of Euros, i.e. billions of Hungarian Forints. It also follows from the support that planned preventive maintenance works must be performed on the renewed and rehabilitated lines. On the other hand, it takes away significant costs from the non-renewed (non-rehabilitated) lines maintenance works, but naturally, less money does not mean less failures, so cost-effective technologies are needed. A segment of maintenance is the local substructure problem(s). In this article, this segment will be mentioned from the development of the failures, through the applied technologies, to the possible new solutions like injection and the using of geosynthetic cementitious composite mats (so called GCCMs).

Context: Cancer Radiomics is an emerging field in medical imaging and refers to the process of converting routine radiological images that are typically qualitatively interpreted to quantifiable descriptions of the tumor phenotypes and when combined with statistical analytics can improve the accuracy of clinical outcome prediction models. However, to understand the radiomic features and their correlation to molecular changes in the tumor, first, there is a need for the development of robust image analysis methods, software tools and statistical prediction models which is often limited in low- and middle-income countries (LMIC). Aims: The aim is to build a framework for machine learning of radiomic features of planning computed tomography (CT) and positron emission tomography (PET) using open source radiomics and data analytics platforms to make it widely accessible to clinical groups. The framework is tested in a small cohort to predict local disease failure following radiation treatment for head-and-neck cancer (HNC). The predictors were also compared with the existing Aerts HNC radiomics signature. Settings and Design: Retrospective analysis of patients with locally advanced HNC between 2017 and 2018 and 31 patients with both pre- and post-radiation CT and evaluation PET were selected. Subjects and Methods: Tumor volumes were delineated on baseline PET using the semi-automatic adaptive-threshold algorithm and propagated to CT; PyRadiomics features (total of 110 under shape/intensity/texture classes) were extracted. Two feature-selection methods were tested for model stability. Models were built based on least absolute shrinkage and selection operator-logistic and Ridge regression of the top pretreatment radiomic features and compared to Aerts' HNC-signature. Average model performance across all internal validation test folds was summarized by the area under the receiver operator curve (ROC). Results: Both feature selection methods selected CT features MCC (GLCM), SumEntropy (GLCM) and Sphericity (Shape) that could predict the binary failure status in the cross-validated group and achieved an AUC >0.7. However, models using Aerts' signature features (Energy, Compactness, GLRLM-GrayLevelNonUniformity and GrayLevelNonUniformity-HLH wavelet) could not achieve a clear separation between outcomes (AUC = 0.51–0.54). Conclusions: Radiomics pipeline included open-source workflows which makes it adoptable in LMIC countries. Additional independent validation of data is crucial for the implementation of radiomic models for clinical risk stratification.

Cr–Mo steel is often used as the material of the hydrogen storage vessel, but its ductility can be deteriorated by high pressure hydrogen, which makes it possible that the local area of strain concentration on the hydrogen storage vessel made of Cr–Mo steel may fail due to excessive plastic deformation. The limit criterion of local strain established according to the study of the fracture strain is the basis for local failure assessment of the vessel. However, the correlation between the fracture strain and the stress state of Cr–Mo steel in high pressure hydrogen is still unclear, so the limit criterion of local strain for hydrogen storage vessel made of Cr–Mo steel has not been established. In this paper, the slow strain rate tensile test (SSRT) of notched specimens with different notch sizes was carried out in air, 45 MPa hydrogen and 100 MPa hydrogen, respectively. Based on the test results, the whole process from tensile to fracture of the specimens was simulated by finite element method. The distribution of stress triaxiality and plastic strain during the tensile process was analyzed, and the correlations between the stress triaxiality and the fracture strain in different environments were obtained. Finally, the limit criterion of local strain for local failure assessment of 4130X hydrogen storage vessel was established. • SSRT of notched specimens made of 4130X steel were carried out in hydrogen. • The whole process from tensile to fracture of the specimens was simulated. • The correlations between the stress triaxiality and fracture strain were obtained. [ABSTRACT FROM AUTHOR]

Purpose: Stereotactic radiosurgery (SRS) has become an important modality in the treatment of brain metastases. The purpose of this study is to investigate the potential of radiomic features from planning magnetic resonance (MR) images and dose maps to predict local failure after SRS for brain metastases. Materials/Methods: Twenty‐eight patients who received Gamma Knife (GK) radiosurgery for brain metastases were retrospectively reviewed in this IRB‐approved study. 179 irradiated tumors included 42 that locally failed within one‐year follow‐up. Using SRS tumor volumes, radiomic features were calculated on T1‐weighted contrast‐enhanced MR images acquired for treatment planning and planned dose maps. 125 radiomic features regarding tumor shape, dose distribution, MR intensities and textures were extracted for each tumor. Logistic regression with automatic feature selection was built to predict tumor progression from local control after SRS. Feature selection and model evaluation using receiver operating characteristic (ROC) curves were performed in a nested cross validation (CV) scheme. The associations between selected radiomic features and treatment outcomes were statistically assessed by univariate analysis. Results: The logistic model with feature selection achieved ROC AUC of 0.82 ± 0.09 on 5‐fold CV, providing 83% sensitivity and 70% specificity for predicting local failure. A total of 10 radiomic features including 1 shape feature, 6 MR images and 3 dose distribution features were selected. These features were significantly associated with treatment outcomes (p < 0.05). The model was validated on independent holdout data with an AUC of 0.78. Conclusions: Radiomic features from planning MR images and dose maps provided prognostic information in SRS for brain metastases. A model built on the radiomic features shows promise for early prediction of tumor local failure after treatment, potentially aiding in personalized care for brain metastases. [ABSTRACT FROM AUTHOR]

Context: Cancer Radiomics is an emerging field in medical imaging and refers to the process of converting routine radiological images that are typically qualitatively interpreted to quantifiable descriptions of the tumor phenotypes and when combined with statistical analytics can improve the accuracy of clinical outcome prediction models. However, to understand the radiomic features and their correlation to molecular changes in the tumor, first, there is a need for the development of robust image analysis methods, software tools and statistical prediction models which is often limited in low- and middle-income countries (LMIC). Aims: The aim is to build a framework for machine learning of radiomic features of planning computed tomography (CT) and positron emission tomography (PET) using open source radiomics and data analytics platforms to make it widely accessible to clinical groups. The framework is tested in a small cohort to predict local disease failure following radiation treatment for head-and-neck cancer (HNC). The predictors were also compared with the existing Aerts HNC radiomics signature. Settings and Design: Retrospective analysis of patients with locally advanced HNC between 2017 and 2018 and 31 patients with both pre- and post-radiation CT and evaluation PET were selected. Subjects and Methods: Tumor volumes were delineated on baseline PET using the semi-automatic adaptive-threshold algorithm and propagated to CT; PyRadiomics features (total of 110 under shape/intensity/texture classes) were extracted. Two feature-selection methods were tested for model stability. Models were built based on least absolute shrinkage and selection operator-logistic and Ridge regression of the top pretreatment radiomic features and compared to Aerts' HNC-signature. Average model performance across all internal validation test folds was summarized by the area under the receiver operator curve (ROC). Results: Both feature selection methods selected CT features MCC (GLCM), SumEntropy (GLCM) and Sphericity (Shape) that could predict the binary failure status in the cross-validated group and achieved an AUC >0.7. However, models using Aerts' signature features (Energy, Compactness, GLRLM-GrayLevelNonUniformity and GrayLevelNonUniformity-HLH wavelet) could not achieve a clear separation between outcomes (AUC = 0.51-0.54). Conclusions: Radiomics pipeline included open-source workflows which makes it adoptable in LMIC countries. Additional independent validation of data is crucial for the implementation of radiomic models for clinical risk stratification. [ABSTRACT FROM AUTHOR]

Objectives: Due to a steadily growing use of stereotactic radiotherapy (SRT) for treatment of brain metastases (BMs), the in-field failure after an initial stereotaxy is an increasingly frequent problem. Repeat stereotactic radiotherapy (re-SRT) shows encouraging results in terms of local control. However, the evidence on prognostic factors limiting the overall survival (OS) of re-treated patients is scarce. Here, we sought to analyze the patients' and treatment characteristics influencing the survival outcomes after re-SRT. Methods: Data of all patients with local failure of initial SRT treated from 2012 to 2019 were retrospectively reviewed and cases treated with salvage SRT were analyzed. We analyzed the impact of patients' and treatment characteristics on overall survival after re-SRT by Kaplan–Meier method and Cox regression models. Local and distant brain control, cause of death, and radionecrosis rate were also assessed. Results: Forty-seven patients with 55 BMs treated with re-SRT were evaluated. Median OS after re-SRT was 9.2 months and the overall local control was 83.6%. Nine BMs (16.4%) presented local relapse (LR), 12 (21.8%) radionecrosis, while 21 patients (44.7%) developed new BMs. Only absence of extracranial metastases at BMs diagnosis (HR 0.42, CI 95%; 0.18–0.97), extracranial disease progression (HR 2.39, CI 95%; 1.06–5.38) and distant brain failure (HR 3.94, CI 95%; 1.68–9.24) after re-SRT were significantly associated with patients' survival. Extracranial progression following re-SRT was an independent prognosticator of worse OS. Conclusion: Re-SRT after LR presented excellent local control with acceptable RN rate and improved patients' survival, limited mainly by extracranial and distant brain progression. [ABSTRACT FROM AUTHOR]

Introduction: Stereotactic radiosurgery (SRS) has been increasingly employed to treat patients with intracranial metastasis, both as a salvage treatment after failed whole brain radiation therapy (WBRT) and as an initial treatment. "Several studies have shown that SRS may be as effective as WBRT with the added benefit of preserving neuro-cognition". However, some patients may have local failure following SRS for intracranial metastasis, defined as increase in total lesion volume by 25% after at least 3 months of follow up. Methods: The SRS registry, established by the Neuro point alliance (NPA) under the auspices of the American Association of Neurological Surgeons (AANS), was queried for patients with intracranial metastasis receiving SRS at the participating sites. Demographic, clinical symptoms, tumor, and treatment characteristics as well as follow up status were summarized for the cohort. A multivariable explanatory cox- regression was performed to evaluate the impact of each of the factors on time to local failure.at last follow-up. Results: A total of 441 patients with 1255 intracranial metastatic lesions undergoing SRS were identified. The most common primary cancer histology was non-small cell lung cancer (43.8%, n = 193). More than half of the cohort had more than 1 metastatic lesion (2–3 lesions: 29.5%, n = 130; more than 3 lesions: 25.2% (n = 111). The average duration of follow-up for the cohort was found to be 8.4 months (SD = 7.61). The mean clinical treatment volume (CTV), after adding together the volume of each lesion for each patient was 5.39 cc (SD = 7.6) at baseline. A total of 20.2% (n = 89) had local failure (increase in volume by > 25%) with a mean time to progression of 7.719 months (SD = 6.09). The progression free survival (PFS) for the cohort at 3, 6 and 12 months were found to be 94.9%, 84.3%, and 69.4%, respectively. On multivariable cox regression analysis, factors associated with increased hazard of local failure included male gender (HR 1.65, 95% CI 1.03–2.66, p = 0.037), chemotherapy at or before SRS (HR = 2.39, 95% CI 1.41–4.05, p = 0.001), WBRT at or before SRS (HR = 2.21, 95% CI 1.16- 4.22, p = 0.017), while surgical resection (HR 0.45, 95% CI 0.21–0. 97, p = 0.04) and immunotherapy (0.34, 95% CI 0.16–0.50, p = 0.014) were associated with lower hazard of local failure. Conclusion: Factors found to be predictive of local failure included higher RPA score and those receiving chemotherapy, while patients undergoing surgical resection and those with occipital lobe lesions were less likely to experience local failure. Our analyses not only corroborate those previously reported but also demonstrate the utility of a multi-institutional registry to advance real-world SRS research for patients with intracranial metastatic lesions. [ABSTRACT FROM AUTHOR]

Background and purpose(1) To establish a method to evaluate dosimetry at the time of primary prostate permanent implant (pPPI) using MRI of the shrunken prostate at the time of failure (tf). (2) To compare cold spot mapping with sextant-biopsy mapping at tf.Material and methodsTwenty-four patients were referred for biopsy-proven local failure (LF) after pPPI. Multiparametric MRI and combined-sextant biopsy with a central review of the pathology at tf were systematically performed. A model of the shrinking pattern was defined as a Volumetric Change Factor (VCF) as a function of time from time of pPPI (t0). An isotropic expansion to both prostate volume (PV) and seed position (SP) coordinates determined at tf was performed using a validated algorithm using the VCF.ResultspPPI CT-based evaluation (at 4weeks) vs. MR-based evaluation: Mean D90% was 145.23±19.16Gy [100.0-167.5] vs. 85.28±27.36Gy [39-139] (p=0.001), respectively. Mean V100% was 91.6±7.9% [70-100%] vs. 73.1±13.8% [55-98%] (p=0.0006), respectively. Seventy-seven per cent of the pathologically positive sextants were classified as cold.ConclusionsPatients with biopsy-proven LF had poorer implantation quality when evaluated by MRI several years after implantation. There is a strong relationship between microscopic involvement at tf and cold spots.

In the past, selection of intermediate clinical endpoints (ICEs) in prostate cancer (PCa) trials largely depended on qualitative assessments; however, the advancing quality of research necessitates a robust correlation with overall survival (OS). This review summarises the results from several high-quality meta-analyses that explored the validity of ICEs as surrogates for OS. We found strong evidence that metastasis-free survival can serve as an ICE in localized PCa. In advanced disease, valid ICEs were identified only within the context of metastatic hormone-sensitive PCa, including radiological and clinical progression-free survival; however, concerns remain regarding their use owing to the limited generalisability of the data used to validate their surrogacy. PATIENT SUMMARY: Intermediate clinical endpoints can reduce the costs of trials and allow earlier introduction of new treatment methods. This article summarises results from studies verifying the validity of these endpoints as surrogates for overall survival., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

A methodology for the probabilistic evaluation of slope stability, capable of disclosing local reliability levels for a certain failure mode of an excavated slope, is proposed in the present work. Probabilistic slope evaluation is conducted upon a deterministically defined slip surface, exposed by the strength reduction method. Computations are performed by combining the probabilistic point estimate method with finite elements. Soil shear strength parameters, φ′ and c′, are treated as random variables of assumed constant variation, following normal distributions. The disclosure of remarkable variation of local slope reliability levels along its critical slip surface, highlights the potential for occurrence of local overstress, in cases where global slope stability is secured. High local probabilities of failure in the overstressed areas of the slope are manifested, despite its low global slope probability of failure. The noteworthy influence of cross-correlation between shear strength parameters, as well as the impact of their uncertainty level on the local probability of failure is discussed. The updated local and global reliability levels, during progressive failure propagation, are also obtained by the model. [ABSTRACT FROM AUTHOR]

• A post-treatment FDG-PET-scan at 4 weeks after concurrent chemoradiotherapy in locally advanced NSCLC-patients was beneficial in response evaluation. • Local and regional treatment response were separately analyzed. • Associations were found amongst post-treatment and relative response metrics with local/regional/distant failure and overall survival. • The associations to these outcomes were mostly observed with the primary tumor. • No preference was found between volumetric and intensity PET-metrics in association to local/regional/distant failure and overall survival. To investigate associations of early post-treatment 18Fluorodeoxyglucose-positron-emission-tomography (FDG-PET)-scans with local (LF), regional (RF), distant failure (DF) and overall survival (OS) in locally advanced non-small cell lung cancer (LA-NSCLC)-patients treated with concurrent chemoradiotherapy. Forty-seven stage IIIA-B NSCLC-patients included in a randomized phase II-trial (NTR2230) received 66 Gy (24x2.75 Gy) with low dose Cisplatin +/− Cetuximab. FDG-PET-scans were performed at baseline and 4 weeks post-treatment (range, 1.6–10.1). SUV max , SUV mean , metabolic tumor volume (MTV), total lesion glycolysis (TLG) and gross tumor volume were calculated separately for the primary tumor and the involved lymph nodes to generate baseline, post-treatment, and relative response metrics defined as (metric pre -metric post)/metric pre. Univariable cox regression analyses were performed to investigate associations between PET-metrics and outcomes. Metrics resulted from the post-treatment scan and relative response were associated with outcome, but baseline metrics were not. Primary tumor metrics were stronger associated with all outcomes than lymph node metrics. Both the volumetric (TLG/MTV) and intensity (SUV max /SUV mean) PET-metrics were associated with OS. The intensity metrics were associated with LF, while the volumetric PET-metrics were associated with RF/DF. This was in contrast to the nodal metrics, demonstrating only an association between RF and the relative response of TLG/MTV. No preference was found between PET volumetric and intensity metrics associated with outcome. Early post-treatment PET-metrics are associated with treatment outcome in LA-NSCLC patients treated with chemoradiotherapy. Both volumetric and intensity PET-metrics are useful, but more for the primary tumor than for lymph nodes. [ABSTRACT FROM AUTHOR]

Objectives/hypothesis: Squamous cell carcinoma originating in the buccal mucosa and retromolar trigone (RMT) have historically poor outcomes. Difficulties in discriminating tumor origin often result in these subsites being combined in surgical and pathological reports. We aimed to determine if making this anatomical distinction has implications for treatment design and clinical outcomes.Study Design: Retrospective case series.Methods: We identified 27 tumors from either the buccal mucosa patients or RMT patients who underwent surgery followed by radiation. For patients who developed a local failure, we fused the pretreatment imaging, simulation computed tomography, and follow-up imaging to determine the location of failures relative to the radiation field. We calculated the 2-year locoregional control and 2-year disease-free survival.Results: The median time from surgery to radiation was 50 days (range, 32-133 days). The 2-year locoregional control for buccal mucosa versus RMT, respectively, were 35.9% versus 68.4% (P = .252). The 2-year disease-free survival rates were 32.7% versus 68.4%, respectively (P = .196). The median times to failure were 12.00 months (range, 4.9-115.0 months) versus 18.5 months (range, 4.5-61.0 months), respectively. All buccal mucosa failures occurred within the high-dose planning target volume, with a median dose of 60 Gy within the failure region. Following locoregional failure, 10 of the 12 patients have died, with a median time from local failure to death of 3.6 months (range, 1-17.6 months).Conclusions: Squamous cell carcinomas of the buccal mucosa appear to have a poor prognosis characterized by rapid in-field failure. Therefore, differentiating tumor origin may be important for prognostication and treatment.Level Of Evidence: 3 Laryngoscope, 130:413-417, 2020. [ABSTRACT FROM AUTHOR]

Embedding single-row piles is often adopted to stabilize slopes in engineering practice. However, for large-scale and complex slopes, single-row piles might not be able to stabilize the slope; rather, double-row piles, even multirow piles, should be adopted. Currently, the optimal locations of double-row stabilizing piles considering local instability of the slope have rarely been studied. In this paper, a simplified analytical model used to analyze double-row pile stabilized slopes is proposed, where the local failure of the slope above the first row of piles is considered. Through the kinematic approach of limit analysis combined with the strength reduction technique, the required resistance forces provided by double-row piles respectively are derived for different pile locations denoted by the rotational angle. Moreover, a framework is developed for analyzing the optimal locations of multirow piles considering multistage potential slip surfaces. The results of an illustrative example are presented, and the reasonableness of the proposed method is verified. It is concluded that the optimal locations of double-row piles lie within middle-lower part of the corresponding stabilized part of the slope. Finally, discussion illustrates the influences of the seismic effects and soil shear strength parameters on the derived optimal pile locations. This study provides novel scientific insight into the optimized design of stabilizing pile locations in engineering practice. [ABSTRACT FROM AUTHOR]

• Local recurrences occur in 10–15% of early stage NSCLC after definitive SBRT. • Salvage SBRT safety and efficacy for local recurrence after initial SBRT is unknown. • Median overall survival after salvage SBRT was 39 months in 21 patients. • Primary tumor and distant control at 2 years were 81% and 75% after salvage. • We observed no grade 3+ AEs, with grade 1–2 pneumonitis in 10% and CW pain in 19% Optimal management of isolated local recurrences after stereotactic body radiation therapy (SBRT) for early non-small cell lung cancer (NSCLC) is unknown and literature describing repeat SBRT for in-field recurrences after initial SBRT are sparse. We investigate the safety and efficacy of salvage SBRT for isolated local failures after initial SBRT for NSCLC. Patients receiving SBRT for isolated local recurrence after initial SBRT for early NSCLC were identified using a prospective registry. Both courses were 3–5 fractions with a biologically effective dose (BED10) of ≥100 Gy. Local failure was defined as within 1 cm of the initial planning target volume (PTV) or an overlap of the ≥25% isodose lines of the first and second treatments. Failures >1 cm beyond the PTV and without ≥25% overlap, or with additional recurrence sites were excluded. Kaplan-Meier analysis was used to estimate survival. A total 21 patients receiving salvage SBRT from 2008 to 2017 were identified. Median interval from initial SBRT to salvage SBRT was 23 months (7–52). Six patients (29%) had central tumors. Median follow-up time from salvage SBRT was 24 months (3–60). Median overall survival after salvage was 39 months. After reirradiation, two-year primary tumor control was 81%, regional nodal control was 89%, distant control was 75% and overall survival was 68%. Grade 2 pneumonitis occurred in 2 patients (10%) and grade 2 chest wall toxicity in 4 patients (19%). No grade 3+ toxicity was observed. Salvage SBRT for isolated local failures after initial SBRT appears safe, with low treatment-related toxicity and encouraging rates of tumor control. [ABSTRACT FROM AUTHOR]

Local instability of a slope widely exists in practice, especially in compound slopes. Based on the deformation energy principle, a new method without any presumption about the shape of the slip surface is proposed for the stability analysis of compound slopes. First, the expression of the safety factor applicable to an arbitrary slope is derived. Then, the stability analysis process/procedure of the slope is given considering local and global instability. Three typical slope examples are studied to verify the efficiency and accuracy of the present method compared with previous methods. Compared with other methods, the proposed method shows good consistency both in terms of the slip surface and safety factor. To investigate the effects of the elastic modulus, Poisson's ratio, internal friction angle, slope angle, step width and depth coefficient on the slope stability and failure mode, a systematic parameter study is carried out. The proposed method in this paper provides a new efficient assessment for slope stability and a reference for the local reinforcement of compound slopes. [ABSTRACT FROM AUTHOR]