Treatment Outcomes of Patients with Ependymoma Receiving Radiotherapy: A Single Institution Experience.

INTRODUCTION: The study explored the failure pattern and clinical outcomes in patients with ependymoma undergoing radiotherapy. METHODS: Between January 2004 and June 2022, we included 32 patients with ependymoma who underwent radiotherapy as part of the multimodality treatment at our institution. Of these, 27 (84.4%) underwent adjuvant radiotherapy, four received radiotherapy after local recurrence, and one received definitive CyberKnife radiotherapy (21 Gy in three fractions). The median prescribed dose was 54 Gy in patients who received conventional radiotherapy. We analyzed the local progression-free survival (LPFS), distant metastasis-free survival (DMFS), progression-free survival (PFS), overall survival (OS), and potential prognostic factors. RESULTS: The median age was 29.8 years. Approximately 28.1% were pediatric patients. Fifteen tumors (46.9%) were World Health Organization (WHO) grade II, 10 (31.3%) were WHO grade III, and seven (22.8%) were WHO grade I. Among them, 15 patients (46.9%) had posterior fossa tumors, 10 (31.3%) had supratentorial tumors, and seven (22.8%) had spinal tumors. Of the 31 patients who underwent upfront surgical resection, 19 (61.3%) underwent gross total resection or near total resection. Seventeen of 19 patients with first failures (89.5%) had isolated local recurrences. Of the 19 patients with disease progression, 11 (57.9%) were disease-free or had stable disease after salvage therapy, and five (26.3%) had disease-related mortality. Most of the first local recurrences after radiotherapy occurred in the infield (13 of 16, 81.3%). The 5-year LPFS, DMFS, PFS, and OS rates were 48.5%, 89.6%, 45.1%, and 88.4%, respectively, at a median follow-up of 6.25 years. Subtotal resection was associated with poorer LPFS and PFS in patients with intracranial ependymoma (hazard ratio = 3.69, p = 0.018 for LPFS; hazard ratio = 3.20, p = 0.029 for PFS). CONCLUSION: Incorporating radiotherapy into multimodal treatment has led to favorable outcomes in patients with ependymoma, and the extent of resection is a prognostic factor for the local control of intracranial ependymoma.

Hybridization Protection Reaction for Sensitive and Robust Gene Expression Profiling of Clinical Formalin-Fixed Paraffin-Embedded Samples.

BACKGROUND: RNA profiling of formalin-fixed paraffin-embedded (FFPE) tumor tissues for the molecular diagnostics of disease prognosis or treatment response is often irreproducible and limited to a handful of biomarkers. This has led to an unmet need for robust multiplexed assays that can profile several RNA biomarkers of interest using a limited amount of specimen. Here, we describe hybridization protection reaction (HPR), which is a novel RNA profiling approach with high reproducibility. METHODS: HPR assays were designed for multiple genes, including 10 radiosensitivity-associated genes, and compared with TaqMan assays. Performance was tested with synthetic RNA fragments, and the ability to analyze RNA was investigated in FPPE samples from 20 normal lung tissues, 40 lung cancer, and 30 esophageal cancer biopsies. RESULTS: Experiments performed on 3 synthetic RNA fragments demonstrated a linear dynamic range of over 1000-fold with a replicate correlation coefficient of 0.99 and high analytical sensitivity between 3.2 to 10 000 pM. Comparison of HPR with standard quantitative reverse transcription polymerase chain reaction on FFPE specimens shows nonsignificant differences with > 99% confidence interval between 2 assays in transcript profiling of 91.7% of test transcripts. In addition, HPR was effectively applied to quantify transcript levels of 10 radiosensitivity-associated genes. CONCLUSIONS: Overall, HPR is an alternative approach for RNA profiling with high sensitivity, reproducibility, robustness, and capability for molecular diagnostics in FFPE tumor biopsy specimens of lung and esophageal cancer.

Prognostication and optimal criteria of circumferential margin involvement for esophageal cancer after chemoradiation and esophagectomy.

Purpose: Circumferential radial margin (CRM) involvement by tumor after resection for esophageal cancer has been suggested as a significant prognostic factor. However, the prognostic value of CRM involvement after surgery with neoadjuvant concurrent chemoradiotherapy (CCRT) is unclear. This study aimed to evaluate the prognostic value of and survival outcomes in CRM involvement as defined by the Royal College of Pathologists (RCP) and the College of American Pathologists (CAP) for patients with esophageal cancer undergoing neoadjuvant CCRT and esophagectomy. Methods: A total of 299 patients with esophageal cancer who underwent neoadjuvant CCRT followed by esophagectomy between 2006 and 2016 were enrolled in our study. The CRM status of the specimens obtained was determined pathologically according to both the CAP and RCP criteria. Survival analyses were performed and compared according to the two criteria. Results: Positive CRM was found in 102 (34.1%) and 40 (13.3%) patients according to RCP and CAP criteria, respectively. The overall and progression-free survival rates were significantly lower in the CRM-positive group than in the CRM-negative group according to both the RCP and CAP criteria. However, under multivariate analysis, in addition to pathological T and N staging of the tumor, only CAP-defined CRM positivity was a significant prognostic factor with adjusted hazard ratios of 2.64 (1.56-4.46) and 2.25 (1.34-3.78) for overall and progression-free survival, respectively (P < 0.001). Conclusion: In patients with esophageal cancer undergoing neoadjuvant CRT followed by esophagectomy, CAP-defined CRM positivity is an independent predictor of survival. Adjuvant therapy should be offered to patients with positive CRM.

Does the Presence of Missing Data Affect the Performance of the SORG Machine-learning Algorithm for Patients With Spinal Metastasis? Development of an Internet Application Algorithm.

BACKGROUND: The Skeletal Oncology Research Group machine-learning algorithm (SORG-MLA) was developed to predict the survival of patients with spinal metastasis. The algorithm was successfully tested in five international institutions using 1101 patients from different continents. The incorporation of 18 prognostic factors strengthens its predictive ability but limits its clinical utility because some prognostic factors might not be clinically available when a clinician wishes to make a prediction. QUESTIONS/PURPOSES: We performed this study to (1) evaluate the SORG-MLA's performance with data and (2) develop an internet-based application to impute the missing data. METHODS: A total of 2768 patients were included in this study. The data of 617 patients who were treated surgically were intentionally erased, and the data of the other 2151 patients who were treated with radiotherapy and medical treatment were used to impute the artificially missing data. Compared with those who were treated nonsurgically, patients undergoing surgery were younger (median 59 years [IQR 51 to 67 years] versus median 62 years [IQR 53 to 71 years]) and had a higher proportion of patients with at least three spinal metastatic levels (77% [474 of 617] versus 72% [1547 of 2151]), more neurologic deficit (normal American Spinal Injury Association [E] 68% [301 of 443] versus 79% [1227 of 1561]), higher BMI (23 kg/m2 [IQR 20 to 25 kg/m2] versus 22 kg/m2 [IQR 20 to 25 kg/m2]), higher platelet count (240 × 103/µL [IQR 173 to 327 × 103/µL] versus 227 × 103/µL [IQR 165 to 302 × 103/µL], higher lymphocyte count (15 × 103/µL [IQR 9 to 21× 103/µL] versus 14 × 103/µL [IQR 8 to 21 × 103/µL]), lower serum creatinine level (0.7 mg/dL [IQR 0.6 to 0.9 mg/dL] versus 0.8 mg/dL [IQR 0.6 to 1.0 mg/dL]), less previous systemic therapy (19% [115 of 617] versus 24% [526 of 2151]), fewer Charlson comorbidities other than cancer (28% [170 of 617] versus 36% [770 of 2151]), and longer median survival. The two patient groups did not differ in other regards. These findings aligned with our institutional philosophy of selecting patients for surgical intervention based on their level of favorable prognostic factors such as BMI or lymphocyte counts and lower levels of unfavorable prognostic factors such as white blood cell counts or serum creatinine level, as well as the degree of spinal instability and severity of neurologic deficits. This approach aims to identify patients with better survival outcomes and prioritize their surgical intervention accordingly. Seven factors (serum albumin and alkaline phosphatase levels, international normalized ratio, lymphocyte and neutrophil counts, and the presence of visceral or brain metastases) were considered possible missing items based on five previous validation studies and clinical experience. Artificially missing data were imputed using the missForest imputation technique, which was previously applied and successfully tested to fit the SORG-MLA in validation studies. Discrimination, calibration, overall performance, and decision curve analysis were applied to evaluate the SORG-MLA's performance. The discrimination ability was measured with an area under the receiver operating characteristic curve. It ranges from 0.5 to 1.0, with 0.5 indicating the worst discrimination and 1.0 indicating perfect discrimination. An area under the curve of 0.7 is considered clinically acceptable discrimination. Calibration refers to the agreement between the predicted outcomes and actual outcomes. An ideal calibration model will yield predicted survival rates that are congruent with the observed survival rates. The Brier score measures the squared difference between the actual outcome and predicted probability, which captures calibration and discrimination ability simultaneously. A Brier score of 0 indicates perfect prediction, whereas a Brier score of 1 indicates the poorest prediction. A decision curve analysis was performed for the 6-week, 90-day, and 1-year prediction models to evaluate their net benefit across different threshold probabilities. Using the results from our analysis, we developed an internet-based application that facilitates real-time data imputation for clinical decision-making at the point of care. This tool allows healthcare professionals to efficiently and effectively address missing data, ensuring that patient care remains optimal at all times. RESULTS: Generally, the SORG-MLA demonstrated good discriminatory ability, with areas under the curve greater than 0.7 in most cases, and good overall performance, with up to 25% improvement in Brier scores in the presence of one to three missing items. The only exceptions were albumin level and lymphocyte count, because the SORG-MLA's performance was reduced when these two items were missing, indicating that the SORG-MLA might be unreliable without these values. The model tended to underestimate the patient survival rate. As the number of missing items increased, the model's discriminatory ability was progressively impaired, and a marked underestimation of patient survival rates was observed. Specifically, when three items were missing, the number of actual survivors was up to 1.3 times greater than the number of expected survivors, while only 10% discrepancy was observed when only one item was missing. When either two or three items were omitted, the decision curves exhibited substantial overlap, indicating a lack of consistent disparities in performance. This finding suggests that the SORG-MLA consistently generates accurate predictions, regardless of the two or three items that are omitted. We developed an internet application (https://sorg-spine-mets-missing-data-imputation.azurewebsites.net/) that allows the use of SORG-MLA with up to three missing items. CONCLUSION: The SORG-MLA generally performed well in the presence of one to three missing items, except for serum albumin level and lymphocyte count (which are essential for adequate predictions, even using our modified version of the SORG-MLA). We recommend that future studies should develop prediction models that allow for their use when there are missing data, or provide a means to impute those missing data, because some data are not available at the time a clinical decision must be made. CLINICAL RELEVANCE: The results suggested the algorithm could be helpful when a radiologic evaluation owing to a lengthy waiting period cannot be performed in time, especially in situations when an early operation could be beneficial. It could help orthopaedic surgeons to decide whether to intervene palliatively or extensively, even when the surgical indication is clear.

Topoisomerase I Inhibition Radiosensitizing Hepatocellular Carcinoma by RNF144A-mediated DNA-PKcs Ubiquitination and Natural Killer Cell Cytotoxicity.

Background and Aims: Topoisomerase I (TOP1) participates the repair of DNA double-strand breaks (DSBs) upon radiation therapy (RT). RNF144A mediates ubiquitination of catalytic subunit of DNA protein kinase (DNA-PKcs), a critical factor in DSB repair. This study aimed to investigate the natural killer (NK) cell-mediated radiosensitization with TOP1 inhibition and the mechanism by DNA-PKcs/RNF144A. Methods: In vitro synergism with TOP1i or cocultured NK cells and RT were evaluated in human hepatocellular carcinoma (HCC) cell lines (Huh7/PLC5) by clonogenic survivals. Orthotopic xenografts were treated with Lipotecan and/or RT. Protein expression was analyzed by western blotting, immunoprecipitation, subcellular fractionation, and confocal microscopy. Results: Lipotecan/RT had a superior synergistic effect to RT on HCC cells. Combined RT/Lipotecan reduced the xenograft size by 7-fold than RT (p<0.05). Lipotecan caused more radiation-induced DNA damage and DNA-PKcs signaling. The expression of major histocompatibility complex class I-related chain A and B (MICA/B) on tumor cells is associated with the sensitivity to NK cell-mediated lysis. Cocultured NK and HCC cells with Lipotecan radiosensitized HCC cells/tissues with the expression of MICA/B. RNF144A increased more in Huh7 cells with combined RT/TOP1i, and reduced the prosurvival function of DNA-PKcs. The effect was reversed by inhibiting the ubiquitin/proteasome system. In comparison, RNF144A decreased through nuclear translocation with the cumulated DNA-PKcs and radio-resistance of PLC5 cells. Conclusions: TOP1i reinforces NK cell-activated anti-HCC effect of RT through RNF144A mediated DNA-PKcs ubiquitination. RNF144A provides a reason for differentiating radiosensitization effect between HCC cells.

Delay of Surgery for Spinal Metastasis due to the COVID-19 Outbreak Affected Patient Outcomes.

OBJECTIVE: The present study is to analyze the effects of the coronavirus disease 2019 (COVID 2019) outbreak and the subsequent lockdown on the outcomes of spinal metastasis patients. METHODS: The study was a retrospective analysis of data from a prospective cohort study. All patients underwent surgical intervention for spinal metastases between January 2019 and December 2021 and had at least 3 months of postoperative follow-up. The primary outcome was overall mortality during the 4 different stages (pre-COVID-19 era, COVID-19 pandemic except in Taiwan, national lockdown, lifting of the lockdown). The secondary outcomes were the oncological severity scores, medical/surgical accessibility, and patient functional outcome during the 4 periods as well as survival/mortality. RESULTS: A total of 233 patients were included. The overall mortality rate was 41.20%. During the Taiwan lockdown, more patients received palliative surgery than other surgical methods, and no total en bloc spondylectomy was performed. The time from surgeon visit to operation was approximately doubled after the COVID-19 outbreak in Taiwan (75.97, 86.63, 168.79, and 166.91 hours in the 4 periods, respectively). The estimated survival probability was highest after the national lockdown was lifted and lowest during the lockdown. In the multivariate analysis, increased risk of mortality was observed with delay of surgery, with emergency surgery having a higher risk with delays above 33 hours, urgent surgery (below 59 and above 111 hours), and elective surgery (above 332 hours). CONCLUSION: The COVID-19 pandemic and related policies have altered daily clinical practice and negatively impacted the survival of patients with spinal metastases.

Radiosensitization effect by HDAC inhibition improves NKG2D-dependent natural killer cytotoxicity in hepatocellular carcinoma.

Background: Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death worldwide. Radiotherapy (RT) controls HCC unsatisfactorily and temporarily. Histone deacetylase inhibitor (HDACi) is a heterogeneous group of epigenetic therapeutics with promising anticancer effects and synergism in combination with RT. HDACi modulates natural killer (NK) cell ligand expression on tumor cells, and leads to immune evasion of cancer cells. Expressions of NK group 2D (NKG2D) ligands on cancer cells determine the cytotoxic effect by interacting with NKG2D receptor on NK cells. However, the role of NKG2D signaling in HCC upon combined RT and HDACi remains unclear. Method: In vitro co-culture system with NK cells was tested for human and murine HCC cell lines. Pan-HDACi (panobinostat) and specific HDAC4 knockdown (HDAC4-KD) were used for HDAC inhibition. Clonogenic assay and flow cytometry examined HCC cell survival and NKG2D ligand expression, respectively. Syngeneic mouse model was used to validate the radiosensitizing effect in vivo. Results: Combined RT and HDACi/HDAC4-KD significantly enhanced NK cell-related cytotoxicity and increased NKG2D ligands, MICA/MICB expressions in human and RAE-1/H60 expressions in murine HCC cells. Delayed tumor growth in vivo by the combinational treatment of RT and HDACi/HDAC4-KD was shown with the associated NKG2D ligand expressions. However, NKG2D receptor did not significantly change among tumors. Conclusion: Radiosensitizing effect with combined RT and HDAC inhibition increased the expression of NKG2D ligands in HCC cells and enhanced their susceptibility to NK cell-mediated cytotoxicity. These findings imply the potential use of combined RT/HDACi and NK cell-directed immunotherapy.

Prognostic significance of lab data and performance comparison by validating survival prediction models for patients with spinal metastases after radiotherapy.

BACKGROUND AND PURPOSE: Well-performing survival prediction models (SPMs) help patients and healthcare professionals to choose treatment aligning with prognosis. This retrospective study aims to investigate the prognostic impacts of laboratory data and to compare the performances of Metastases location, Elderly, Tumor primary, Sex, Sickness/comorbidity, and Site of radiotherapy (METSSS) model, New England Spinal Metastasis Score (NESMS), and Skeletal Oncology Research Group machine learning algorithm (SORG-MLA) for spinal metastases (SM). MATERIALS AND METHODS: From 2010 to 2018, patients who received radiotherapy (RT) for SM at a tertiary center were enrolled and the data were retrospectively collected. Multivariate logistic and Cox-proportional-hazard regression analyses were used to assess the association between laboratory values and survival. The area under receiver-operating characteristics curve (AUROC), calibration analysis, Brier score, and decision curve analysis were used to evaluate the performance of SPMs. RESULTS: A total of 2786 patients were included for analysis. The 90-day and 1-year survival rates after RT were 70.4% and 35.7%, respectively. Higher albumin, hemoglobin, or lymphocyte count were associated with better survival, while higher alkaline phosphatase, white blood cell count, neutrophil count, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, or international normalized ratio were associated with poor prognosis. SORG-MLA has the best discrimination (AUROC 90-day, 0.78; 1-year 0.76), best calibrations, and the lowest Brier score (90-day 0.16; 1-year 0.18). The decision curve of SORG-MLA is above the other two competing models with threshold probabilities from 0.1 to 0.8. CONCLUSION: Laboratory data are of prognostic significance in survival prediction after RT for SM. Machine learning-based model SORG-MLA outperforms statistical regression-based model METSSS model and NESMS in survival predictions.

Clinical outcomes for patients with thymoma and thymic carcinoma after undergoing different front-line chemotherapy regimens.

BACKGROUND: Front-line platinum-base chemotherapy for advanced thymoma and thymic carcinoma (TC) improves resectability and prolongs patients' overall survival (OS). In this study, we evaluated patients' outcomes given different front-line regimens: cisplatin, doxorubicin, and cyclophosphamide (CAP); cisplatin and etoposide (EP); or cisplatin and paclitaxel (TP). MATERIALS AND METHODS: We retrospectively evaluated the medical records of patients with advanced thymoma and TC who were treated at our medical center between 2005 and 2015. We investigated objective response rates (ORRs), progression-free survival (PFS), and OS after undergoing different front-line regimens. RESULTS: Among the 108 enrolled patients, 37 (34%) had thymoma and 71 (66%) had TC; 45 received CAP, 36 received EP, and 27 received TP regimens. The ORRs of patients receiving CAP, EP, and TP were 51%, 50%, and 41%, respectively. For patients with stage III and IVA disease, the median PFS after CAP, EP, and TP were 34.5, 26.4, and 18.0 months (p = 0.424), respectively, and the 5-year OS rates were 84.9%, 70.6%, and 60.0% (p = 0.509). In patients with stage IVB disease, the median PFS were 9.4, 8.2, and 11.6 months after undergoing CAP, EP, and TP (p = 0.173), respectively, and the 5-year OS rates were 41.1%, 39.1%, and 14.3% (p = 0.788). TC pathology subtype and liver metastasis were associated with poor OS. Three patients with stage IVB TC had an OS of more than 5 years. CONCLUSION: Different front-line chemotherapy regimens may provide similar long-term PFS and OS in patients with advanced thymoma and TC. In addition to TC and liver metastasis were associated with poor OS, other potential prognostic factors are warranted for studying.

Kinetics and Mechanism of In Situ Metallization of Bulk DNA Films.

DNA-templated metallization is broadly investigated in the fabrication of metallic structures by virtue of the unique DNA-metal ion interaction. However, current DNA-templated synthesis is primarily carried out based on pure DNA in an aqueous solution. In this study, we present in situ synthesis of metallic structures in a natural DNA complex bulk film by UV light irradiation, where the growth of silver particles is resolved by in situ time-resolved small-angle X-ray scattering and dielectric spectroscopy. Our studies provide physical insights into the kinetics and mechanisms of natural DNA metallization, in correlation with the multi-stage switching operations in the bulk phase, paving the way towards the development of versatile biomaterial composites with tunable physical properties for optical storage, plasmonics, and catalytic applications.

The intracranial tumor segmentation challenge: Contour tumors on brain MRI for radiosurgery.

We report the set-up of the Intracranial Tumor Segmentation (ICTS) dataset. This dataset was retrieved from clinical work of radiosurgery, contoured by qualified neurosurgeons and radiation oncologists. It contains contrast-enhanced T1-weighted images of 1500 patients, together with the labels of tumors to be treated. The ICTS image data and manual annotations continue to be publicly available through an online evaluation system as an ongoing benchmarking resource.

Preclinical evaluation of PEGylated liposomal doxorubicin as an effective radiosensitizer in chemoradiotherapy for lung cancer.

PURPOSE: Development of a safe and effective systemic chemotherapeutic agent for concurrent administration with definitive thoracic radiotherapy remains a major goal of lung cancer management. The synergistic effect of PEGylated liposomal doxorubicin and irradiation was evaluated in lung cancer cell lines both in vitro and in vivo. METHODS: In vitro radiosensitization of A549 and LLC cell lines was evaluated by colony formation assay, γH2AX fluorescent staining and western blot assay, and annexin V staining. A radiosensitization study with healthy human lung-derived cell line BEAS-2B was performed for comparative purposes. In vivo radiosensitization was evaluated by tumor ectopic growth, cell survival, pharmacokinetics, and biodistribution analyses. Cleaved caspase­3, the marker for apoptosis, was assessed immunohistochemically in A549 xenograft tumors. RESULTS: Treatment with PEGylated liposomal doxorubicin decreased A549 and LLC cell proliferation in a dose-dependent manner. In vitro studies revealed comparable radiosensitizer advantages of PEGylated liposomal doxorubicin and free doxorubicin, showing equivalent DNA double-strand breaks according to γH2AX fluorescent staining and western blot assays, similar numbers of apoptotic cells in the annexin­V staining assay, and moderately decreased clonogenic survival. In vivo studies demonstrated markedly slow ectopic tumor growth with prolonged survival following treatment with PEGylated liposomal doxorubicin plus irradiation in both A549 and LLC mouse models, suggesting that PEGylated liposomal doxorubicin is more effective as a radiosensitizer than free doxorubicin in vivo. Pharmacokinetics evaluation showed a longer half-life of approximately 40 h for PEGylated liposomal doxorubicin, confirming that the liposomal carrier achieved controlled release. Biodistribution evaluation of PEGylated liposomal doxorubicin confirmed high accumulation of doxorubicin in tumors, indicating the promising drug delivery attributes of PEGylated liposomal doxorubicin. Although free doxorubicin caused histopathologic myocarditis with the cardiac muscle fibers showing varying degrees of damage, PEGylated liposomal doxorubicin caused no such effects. The immunohistochemical expression of cleaved caspase-3-positive cells was greatest expressed in the irradiation and PEGylated liposomal doxorubicin combined treatment group, indicating prolonged tumoricidal effects. CONCLUSIONS: Our study provides preclinical in vitro and in vivo evidence of the effectiveness of PEGylated liposomal doxorubicin as a radiosensitizer, supporting its potential clinical development as a component of chemoradiotherapy.

Peri-radiosurgical administration of bevacizumab improves radiographic response to single and fractionated stereotactic radiosurgery for large brain metastasis.

INTRODUCTION: Stereotactic radiosurgery (SRS) is a standard of care for brain metastases (BM) patients, yet large BM are at a greater risk for radionecrosis and local progression (LP). Concomitant bevacizumab and radiotherapy has been shown to improve outcomes in primary and metastatic brain tumors. This retrospective study investigated the efficacy and safety of concurrent bevacizumab and SRS for large BM. METHODS: From 2015 to 2019, patients with a BM diameter ≥ 2 cm who received either combination therapy (n = 49, SRS + BVZ group), or SRS alone (n = 73, SRS group) were enrolled. Bevacizumab was given peri-radiosurgically with a 2-week interval. Radiographic response was assessed using the RECIST version 1.1. Competing risk and logistic regression analysis were performed to evaluate prognostic factors. RESULTS: Radiographic response was achieved in 41 patients (84%) in the SRS + BVZ group and 37 patients (51%) in the SRS group (p = 0.001). In the multivariate regression analysis, concurrent bevacizumab was independently associated with a better radiographic response (p = 0.003). The cumulative incidences of LP and ≥ grade 2 radionecrosis at 12 months between the SRS + BVZ group and SRS group were 2% versus 6.8%, and 14.3% versus 14.6%, respectively. For patients with BM size ≥ 3 cm, the cumulative incidence of LP was significantly lower in the SRS + BVZ group (p = 0.03). No ≥ grade 4 toxicity was observed in either group. CONCLUSIONS: Concurrent bevacizumab and SRS for large BM is highly effective, with a better radiographic response and minimal excessive treatment-related toxicities. Peri-radiosurgical bevacizumab preferentially reduced the risk of LP, especially for BM size ≥ 3 cm.

Design of a motion simulation system to assist respiratory gating for radiation therapy.

Stereotactic ablative radiotherapy (SABR) aims to deliver high doses of radiation to kill cancer cells and shrink tumors in less than or equal to 6 fractions. However, organ motion during treatment is a challenging issue for this kind of technique. We develop a control system via Bluetooth technology to simulate and correct body motion during SABR. METHODS: Radiation doses were analyzed, and the radiation damage protection capability was checked by external beam therapy 3 (EBT3) films irradiated by a linear accelerator. A wireless signal test was also performed. A validation was performed with 8 previously treated patient respiratory pattern records and 8 healthy volunteers. RESULTS: The homemade simulation system consisted of 2 linear actuators, one movable stage with a maximal moving distance of 6.5 cm × 12.5 cm × 5 cm to simulate the respiratory pattern of 8 patients precisely with a median error of 0.36 mm and a maximal motion difference of 1.17 mm, and 3.17 and chipset transited signals to display them as a waveform. From the test with 8 volunteers, the chip could detect deep respiratory movement up to 3 cm. The effect of the chip on a radiation dose of 400 monitor units (MUs) by 6 MV photons and 200 MUs by 10 MV photons showed high penetration rates of 98.8% and 98.6%, respectively. CONCLUSIONS: We invented a tubeless and wireless respiratory gating detection chip. The chip has minimal interference with the treatment angles, good noise immunity and the capability to easily penetrate a variety of materials. The simulation system consisting of linear actuators also successfully simulates the respiratory pattern of real patients.

Randomized multi-reader evaluation of automated detection and segmentation of brain tumors in stereotactic radiosurgery with deep neural networks.

BACKGROUND: Stereotactic radiosurgery (SRS), a validated treatment for brain tumors, requires accurate tumor contouring. This manual segmentation process is time-consuming and prone to substantial inter-practitioner variability. Artificial intelligence (AI) with deep neural networks have increasingly been proposed for use in lesion detection and segmentation but have seldom been validated in a clinical setting. METHODS: We conducted a randomized, cross-modal, multi-reader, multispecialty, multi-case study to evaluate the impact of AI assistance on brain tumor SRS. A state-of-the-art auto-contouring algorithm built on multi-modality imaging and ensemble neural networks was integrated into the clinical workflow. Nine medical professionals contoured the same case series in two reader modes (assisted or unassisted) with a memory washout period of 6 weeks between each section. The case series consisted of 10 algorithm-unseen cases, including five cases of brain metastases, three of meningiomas, and two of acoustic neuromas. Among the nine readers, three experienced experts determined the ground truths of tumor contours. RESULTS: With the AI assistance, the inter-reader agreement significantly increased (Dice similarity coefficient [DSC] from 0.86 to 0.90, P < 0.001). Algorithm-assisted physicians demonstrated a higher sensitivity for lesion detection than unassisted physicians (91.3% vs 82.6%, P = .030). AI assistance improved contouring accuracy, with an average increase in DSC of 0.028, especially for physicians with less SRS experience (average DSC from 0.847 to 0.865, P = .002). In addition, AI assistance improved efficiency with a median of 30.8% time-saving. Less-experienced clinicians gained prominent improvement on contouring accuracy but less benefit in reduction of working hours. By contrast, SRS specialists had a relatively minor advantage in DSC, but greater time-saving with the aid of AI. CONCLUSIONS: Deep learning neural networks can be optimally utilized to improve accuracy and efficiency for the clinical workflow in brain tumor SRS.

A retrospective study of clinicopathologic and molecular features of inoperable early-stage non-small cell lung cancer treated with stereotactic ablative radiotherapy.

BACKGROUND/PURPOSE: Stereotactic ablative radiotherapy (SABR) is the treatment of choice for medically inoperable, early-stage non-small cell lung cancer (ES-NSCLC). The influence of oncogenic driver alterations and comorbidities are not well known. Here we present treatment outcomes based on clinicopathologic features and molecular profiles. METHODS: We retrospectively analyzed patients treated with SABR for inoperable ES-NSCLC. Molecular features of oncogenic driver alterations included EGFR, ALK, and ROS1. Comorbidities were assessed using the age-adjusted Charlson Comorbidity Index (ACCI). Survival was calculated using the Kaplan-Meier method. The Cox regression model was performed for univariate and multivariate analyses of prognostic factors. Competing risk analysis was used to evaluate the cumulative incidence of disease progression. RESULTS: From 2008 to 2020, 100 patients (median age: 82 years) were enrolled. The majority of patients were male (64%), ever-smokers (60%), and had adenocarcinoma (65%). With a median follow-up of 21.5 months, the median overall survival (OS) and real-world progression-free survival were 37.7 and 25.1 months, respectively. The competing-risk-adjusted 3-year cumulative incidences of local, regional, and disseminated failure were 8.2%, 14.5%, and 31.2%, respectively. An ACCI ≥7 was independently associated with inferior OS (hazard ratio [HR] 2.45, p = 0.03). Tumor size ≥4 cm (HR 4.16, p < 0.001) was the most important independent prognostic factor predicting real-world progression. EGFR mutation status had no impact on the outcomes. CONCLUSION: SABR provides excellent local control in ES-NSCLC, although disseminated failures remains a major concern. ACCI is the best indicator for OS, while tumor sizes ≥4 cm predicts poor disease control.

Circulating Exosomal Integrin ß3 Is Associated with Intracranial Failure and Survival in Lung Cancer Patients Receiving Cranial Irradiation for Brain Metastases: A Prospective Observational Study.

Brain metastasis (BM) is a major problem in patients with cancer. Exosomes or extracellular vesicles (EV) and integrins contribute to the development of BM, and exosomal integrins have been shown to determine organotropic metastasis. We hypothesized that circulating EV integrins are able to influence the failure patterns and outcomes in patients treated for BM. We prospectively enrolled 75 lung cancer patients with BM who received whole brain radiotherapy (WBRT). We isolated and quantified their circulating EV integrins, and analyzed the association of EV integrins with clinical factors, survival, and intracranial/extracranial failure. Circulating EV integrin levels were independent of age, sex, histology, number of BM, or graded prognostic assessment score. Age, histology, and graded prognostic assessment score correlated with survival. Patients with higher levels of circulating EV integrin ß3 had worse overall survival (hazard ratio: 1.15 per 1 ng/mL increase; p = 0.04) following WBRT. Multivariate regression analysis also showed a higher cumulative incidence of intracranial failure (subdistribution hazard ratio: 1.216 per 1 ng/mL increase; p = 0.037). In conclusion, circulating EV integrin ß3 levels correlated with survival and intracranial control of patients with lung cancer after WBRT for BM. This supports that EV integrin ß3 mediates a brain-tropic metastasis pattern, and may serve as a novel prognostic biomarker for BM.

Hippocampal avoidance whole-brain radiotherapy without memantine in preserving neurocognitive function for brain metastases: a phase II blinded randomized trial.

BACKGROUND: Hippocampal avoidance whole-brain radiotherapy (HA-WBRT) shows potential for neurocognitive preservation. This study aimed to evaluate whether HA-WBRT or conformal WBRT (C-WBRT) is better for preserving neurocognitive function. METHODS: This single-blinded randomized phase II trial enrolled patients with brain metastases and randomly assigned them to receive HA-WBRT or C-WBRT. Primary endpoint is decline of the Hopkins Verbal Learning Test-Revised (HVLT-R) delayed recall at 4 months after treatment. Neurocognitive function tests were analyzed with a mixed effect model. Brain progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method. RESULTS: From March 2015 to December 2018, seventy patients were randomized to yield a total cohort of 65 evaluable patients (33 in the HA-WBRT arm and 32 in the C-WBRT arm) with a median follow-up of 12.4 months. No differences in baseline neurocognitive function existed between the 2 arms. The mean change of HVLT-R delayed recall at 4 months was -8.8% in the HA-WBRT arm and +3.8% in the C-WBRT arm (P = 0.31). At 6 months, patients receiving HA-WBRT showed favorable perpetuation of HVLT-R total recall (mean difference = 2.60, P = 0.079) and significantly better preservation of the HVLT-R recognition-discrimination index (mean difference = 1.78, P = 0.019) and memory score (mean difference = 4.38, P = 0.020) compared with patients undergoing C-WBRT. There were no differences in Trail Making Test Part A or Part B or the Controlled Oral Word Association test between the 2 arms at any time point. There were no differences in brain PFS or OS between arms as well. CONCLUSION: Patients receiving HA-WBRT without memantine showed better preservation in memory at 6-month follow-up, but not in verbal fluency or executive function.

Precision radiotherapy for non-small cell lung cancer.

Precision medicine is becoming the standard of care in anti-cancer treatment. The personalized precision management of cancer patients highly relies on the improvement of new technology in next generation sequencing and high-throughput big data processing for biological and radiographic information.Systemic precision cancer therapy has been developed for years. However, the role of precision medicine in radiotherapy has not yet been fully implemented. Emerging evidence has shown that precision radiotherapy for cancer patients is possible with recent advances in new radiotherapy technologies, panomics, radiomics and dosiomics.This review focused on the role of precision radiotherapy in non-small cell lung cancer and demonstrated the current landscape.