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1.
J Clin Oncol ; : JCO2302075, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39374473

RESUMO

PURPOSE: This multicenter, randomized, phase III clinical trial (Northern Radiation Oncology Group of China-002) focused on patients with oligo-organ metastatic non-small cell lung cancer (NSCLC) who have epidermal growth factor receptor (EGFR) mutations. We aimed to investigate whether first-line concurrent thoracic radiotherapy (TRT) and EGFR-tyrosine kinase inhibitors (TKIs), compared with TKIs alone, could achieve better survival. MATERIALS AND METHODS: The patients in the TKI plus TRT group received 60 Gy to primary lung tumor and positive regional lymph nodes. Radiotherapy for metastases to other sites was determined by clinicians. The primary end point was the progression-free survival (PFS). Secondary end points included overall survival (OS) and treatment-related adverse events (TRAEs). The first and second interim analyses were performed in March 2021 and March 2022. RESULTS: Between April 14, 2016, and February 25, 2022, a total of 118 patients were enrolled. Compared with the TKI alone group, the TKI plus TRT group achieved significantly better PFS (hazard ratio [HR], 0.57; P = .004) and OS (HR, 0.62; P = .029). The median PFS was 10.6 months in the TKI alone group and 17.1 months in the TKI plus TRT group. The median OS was 26.2 months and 34.4 months in the TKI alone group and TKI plus TRT group, respectively. The TKI plus TRT group showed better local control but was associated with a higher incidence of severe TRAEs (11.9% v 5.1%). CONCLUSION: For patients with EGFR-mutated oligo-organ metastatic NSCLC treated with first-line EGFR-TKIs, concurrent TRT improves the PFS and OS, and TRAEs are acceptable and tolerable.

2.
Org Lett ; 26(38): 8057-8062, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39248598

RESUMO

Numerous effective bioisosteric replacements have been identified through substituting scaffolds and functional groups in lead molecules with alternative ones that preserve or enhance the desired biological activity of the original compound. Here, a copper-catalyzed nucleophilic cycloisomerization was developed to access potential bioisosteric replacements of azepinoindole. In this process, "tetra-alkene" characteristic of indolizine undergoes a 12π electrocyclization, offering a complementary method to obtain azepinoindolizine derivatives that are otherwise challenging to prepare through conventional means.

3.
Adv Healthc Mater ; : e2401131, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39225395

RESUMO

Bacterial infections can pose significant health risks as they have the potential to cause a range of illnesses. These infections can spread rapidly and lead to complications if not promptly diagnosed and treated. Therefore, it is of great significance to develop a probe to selectively target and image pathogenic bacteria while simultaneously killing them, as there are currently no effective clinical solutions available. This study presents a novel approach using near-infrared carbonized polymer dots (NIR-CPDs) for simultaneous in vivo imaging and treatment of bacterial infections. The core-shell structure of the NIR-CPDs facilitates their incorporation into bacterial cell membranes, leading to an increase in fluorescence brightness and photostability. Significantly, the NIR-CPDs exhibit selective bacterial-targeting properties, specifically identifying Staphylococcus aureus (S. aureus) while sparing Escherichia coli (E. coli). Moreover, under 808 nm laser irradiation, the NIR-CPDs exhibit potent photodynamic effects by generating reactive oxygen species that target and damage bacterial membranes. In vivo experiments on infected mouse models demonstrate not only precise imaging capabilities but also significant therapeutic efficacy, with marked improvements in wound healing. The study provides the dual-functional potential of NIR-CPDs as a highly effective tool for the advancement of medical diagnostics and therapeutics in the fight against bacterial infections.

4.
PLoS One ; 19(9): e0305282, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39302947

RESUMO

Samples from two outcrop sections, MGS1 and DGS1 of Milanggouwan and Dishaogouwan in the Salawusu River Basin, were studied in terms of grain size using end-member model. Results show that: 1) MGS1 layer particles are more concentrated, better sorting, and smaller skewness and kurtosis values than those of DGS1. Whereas in the upper part of the DGS1 section, the grain size of the paleodune is coarser, with better sorting and sharper peak, comparing with the lower lacustrine sediments. 2) Three end-member components, EM1 (end-member 1), EM2 (end-member 2) and EM3 (end-member 3), which reflect sedimentary dynamic characteristics, are extracted by end-member analysis. The EM1 indicates the hydrodynamic force with great variation, EM2 indicates transporting force by flowing water and EM3 indicates the depositional environment closely related to the wind activity. 3) According to the accumulation processes of MGS1 and DGS1 strata, a total of four climate periods can be identified, namely early warming period, Holocene peak period, fluctuating transition to cold period and unstable cooling period. Moreover, EM1 of MGS1 and DGS1 is basically consistent with both the sea surface temperature (SST) in the western tropical Pacific and global temperature trends during the Holocene, suggesting that the environmental fluctuations recorded by MGS1 and DGS1 can be correlated with each other.


Assuntos
Sedimentos Geológicos , Rios , Rios/química , Sedimentos Geológicos/análise , Modelos Teóricos , Clima
5.
BMC Cancer ; 24(1): 1086, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39223503

RESUMO

BACKGROUND: This study aimed to establish a consensus on the delineation of target volumes for neoadjuvant radiation therapy (nRT) in esophageal squamous cell carcinoma (ESCC) within China. METHODS: From February 2020 to June 2021, nine ESCC patients who received nRT were retrospectively selected from Sun Yat-sen University Cancer Center and Shandong Cancer Hospital. A panel from eight cancer radiotherapy centers performed two rounds of nRT target volume delineation for these patients: the first round for cases 1-6 and the second for cases 7-9. Online meetings were held after each delineation round to discuss findings. The consistency of delineations across centers was compared using mean undirected Hausdorff distances (Hmean), dice similarity coefficients (DSC), and total volumes, analyzed with the Mann-Whitney U test. RESULTS: The second round of delineations showed improved consistency across centers (total clinical target volume (CTVtotal): mean DSC = 0.76-0.81; mean Hmean = 2.11-3.14 cm) compared to the first round (CTVtotal: mean DSC = 0.63-0.64; mean Hmean = 5.66-7.34 cm; DSC and Hmean: P < 0.050 between rounds), leading to the formation of a consensus and an atlas for ESCC nRT target volume delineation. A proposal was reached through evaluating target volume delineations, analyzing questionnaire survey outcomes, and reviewing pertinent literature. CONCLUSIONS: We have developed guidelines and an atlas for target volume delineation in nRT therapy for ESCC in China. These resources are designed to facilitate more consistent delineation of target volumes in both clinical practice and clinical trials.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Terapia Neoadjuvante , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , China , Neoplasias Esofágicas/radioterapia , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/radioterapia , Carcinoma de Células Escamosas do Esôfago/patologia , Terapia Neoadjuvante/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Estudos Retrospectivos
6.
Org Lett ; 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39284305

RESUMO

This study reported a convergent pattern to stereospecifically synthesize 4,5-dihydrogen azepine from simple and readily available starting materials, addressing synthetic and stereoselective issues. Several synthetically important transformations, such as Simmon-Smith cyclopropanation, halogenation, and hydrogenation, demonstrated the utilities of this strategy. Particularly, the final azepine products could effectively contract into highly substituted pyridine derivatives through an intramolecular oxidation rearrangement.

7.
Cancer Commun (Lond) ; 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39161079

RESUMO

BACKGROUND: Concurrent chemoradiotherapy (CCRT) is the standard treatment for locally advanced esophageal squamous cell carcinoma (ESCC). However, the optimal radiotherapy regimen, particularly in terms of total dose and planned range of irradiation field, remains unclear. This phase III clinical trial aimed to compare the survival benefits between different radiation doses and different target fields. METHODS: This trial compared two aspects of radiation treatment, total dose and field, using a two-by-two factorial design. The high-dose (HD) group received 59.4 Gy radiation, and the standard-dose (SD) group received 50.4 Gy. The involved field irradiation (IFI) group and elective nodal irradiation (ENI) group adopted different irradiation ranges. The participants were assigned to one of the four groups (HD+ENI, HD+IFI, SD+ENI and SD+IFI). The primary endpoint was overall survival (OS), and the secondary endpoints included progression-free survival (PFS). The synergy indexwas used to measure the interaction effect between dose and field. RESULTS: The interaction analysis did not reveal significant synergistic effects between the dose and irradiation field. In comparison to the target field, patients in IFI or ENI showed similar OS (hazard ratio [HR] = 0.99, 95% CI: 0.80-1.23, p = 0.930) and PFS (HR = 1.02, 95% CI: 0.82-1.25). The HD treatment did not show significantly prolonged OS compared with SD (HR = 0.90, 95% CI: 0.72-1.11, p = 0.318), but it suggested improved PFS (25.2 months to 18.0 months). Among the four groups, the HD+IFI group presented the best survival, while the SD+IFI group had the worst prognosis. No significant difference in the occurrence of severe adverse events was found in dose or field comparisons. CONCLUSIONS: IFI demonstrated similar treatment efficacy to ENI in CCRT of ESCC. The HD demonstrated improved PFS, but did not significantly improve OS. The dose escalation based on IFI (HD+IFI) showed better therapeutic efficacy than the current recommendation (SD+ENI) and is worth further validation.

8.
bioRxiv ; 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39211079

RESUMO

Monocyte-derived macrophages recruited to injured tissues induce a maladaptive fibrotic response characterized by excessive production of collagen by local fibroblasts. Macrophages initiate this programming via paracrine factors, but it is unknown whether reciprocal responses from fibroblasts enhance profibrotic polarization of macrophages. We identify macrophage-fibroblast crosstalk necessary for injury-associated fibrosis, in which macrophages induced interleukin 6 ( IL-6 ) expression in fibroblasts via purinergic receptor P2rx4 signaling, and IL-6, in turn, induced arginase 1 ( Arg1 ) expression in macrophages. Arg1 contributed to fibrotic responses by metabolizing arginine to ornithine, which fibroblasts used as a substrate to synthesize proline, a uniquely abundant constituent of collagen. Imaging of idiopathic pulmonary fibrosis (IPF) lung samples confirmed expression of ARG1 in myeloid cells, and arginase inhibition suppressed collagen expression in cultured precision-cut IPF lung slices. Taken together, we define a circuit between macrophages and fibroblasts that facilitates cross-feeding metabolism necessary for injury-associated fibrosis.

9.
Cancer Cell ; 42(7): 1258-1267.e2, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38906157

RESUMO

We conducted a proof-of-concept, phase 2 trial to assess neoadjuvant SHR-1701 with or without chemotherapy, followed by surgery or radiotherapy, and then consolidation SHR-1701 in unresectable stage III non-small-cell lung cancer (NSCLC). In the primary cohort of patients receiving neoadjuvant combination therapy (n = 97), both primary endpoints were met, with a post-induction objective response rate of 58% (95% confidence interval [CI] 47-68) and an 18-month event-free survival (EFS) rate of 56.6% (95% CI 45.2-66.5). Overall, 27 (25%) patients underwent surgery; all achieved R0 resection. Among them, 12 (44%) major pathological responses and seven (26%) pathological complete responses were recorded. The 18-month EFS rate was 74.1% (95% CI 53.2-86.7) in surgical patients and 57.3% (43.0-69.3) in radiotherapy-treated patients. Neoadjuvant SHR-1701 with chemotherapy, followed by surgery or radiotherapy, showed promising efficacy with a tolerable safety profile in unresectable stage III NSCLC. Surgical conversion was feasible in a notable proportion of patients and associated with better survival outcomes.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Terapia Neoadjuvante , Estadiamento de Neoplasias , Estudo de Prova de Conceito , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/terapia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/mortalidade , Feminino , Terapia Neoadjuvante/métodos , Pessoa de Meia-Idade , Masculino , Idoso , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Anticorpos Monoclonais , Proteínas Recombinantes de Fusão
10.
Org Lett ; 26(20): 4183-4188, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38742794

RESUMO

We present a novel approach for the skeletal rearrangement of an oxazole into an azepine and pyrrole through a dynamic electrocyclization process, showing an innovative, unconventional reaction sequence. This method enables precise control of regioselectivity in competitive 6π and 8π electrocyclization reactions, rendering the final products rich in functional groups that can be further developed for the synthesis of nitrogen-containing scaffolds. This is an unprecedented example of the selective synthesis of seven- and five-member heterocycles via dynamic electrocyclization ring opening or closure.

11.
IEEE J Biomed Health Inform ; 28(10): 6031-6041, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38809720

RESUMO

The Segment Anything Model (SAM) is a foundational model that has demonstrated impressive results in the field of natural image segmentation. However, its performance remains suboptimal for medical image segmentation, particularly when delineating lesions with irregular shapes and low contrast. This can be attributed to the significant domain gap between medical images and natural images on which SAM was originally trained. In this paper, we propose an adaptation of SAM specifically tailored for lesion segmentation termed LeSAM. LeSAM first learns medical-specific domain knowledge through an efficient adaptation module and integrates it with the general knowledge obtained from the pre-trained SAM. Subsequently, we leverage this merged knowledge to generate lesion masks using a modified mask decoder implemented as a lightweight U-shaped network design. This modification enables better delineation of lesion boundaries while facilitating ease of training. We conduct comprehensive experiments on various lesion segmentation tasks involving different image modalities such as CT scans, MRI scans, ultrasound images, dermoscopic images, and endoscopic images. Our proposed method achieves superior performance compared to previous state-of-the-art methods in 8 out of 12 lesion segmentation tasks while achieving competitive performance in the remaining 4 datasets. Additionally, ablation studies are conducted to validate the effectiveness of our proposed adaptation modules and modified decoder.


Assuntos
Algoritmos , Interpretação de Imagem Assistida por Computador , Humanos , Interpretação de Imagem Assistida por Computador/métodos
12.
BMC Cancer ; 24(1): 460, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609892

RESUMO

BACKGROUND: To predict pathological complete response (pCR) in patients receiving neoadjuvant immunochemotherapy (nICT) for esophageal squamous cell carcinoma (ESCC), we explored the factors that influence pCR after nICT and established a combined nomogram model. METHODS: We retrospectively included 164 ESCC patients treated with nICT. The radiomics signature and hematology model were constructed utilizing least absolute shrinkage and selection operator (LASSO) regression, and the radiomics score (radScore) and hematology score (hemScore) were determined for each patient. Using the radScore, hemScore, and independent influencing factors obtained through univariate and multivariate analyses, a combined nomogram was established. The consistency and prediction ability of the nomogram were assessed utilizing calibration curve and the area under the receiver operating factor curve (AUC), and the clinical benefits were assessed utilizing decision curve analysis (DCA). RESULTS: We constructed three predictive models.The AUC values of the radiomics signature and hematology model reached 0.874 (95% CI: 0.819-0.928) and 0.772 (95% CI: 0.699-0.845), respectively. Tumor length, cN stage, the radScore, and the hemScore were found to be independent factors influencing pCR according to univariate and multivariate analyses (P < 0.05). A combined nomogram was constructed from these factors, and AUC reached 0.934 (95% CI: 0.896-0.972). DCA demonstrated that the clinical benefits brought by the nomogram for patients across an extensive range were greater than those of other individual models. CONCLUSIONS: By combining CT radiomics, hematological factors, and clinicopathological characteristics before treatment, we developed a nomogram model that effectively predicted whether ESCC patients would achieve pCR after nICT, thus identifying patients who are sensitive to nICT and assisting in clinical treatment decision-making.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Terapia Neoadjuvante , Carcinoma de Células Escamosas do Esôfago/diagnóstico por imagem , Carcinoma de Células Escamosas do Esôfago/terapia , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/tratamento farmacológico , Nomogramas , Radiômica , Estudos Retrospectivos
13.
Quant Imaging Med Surg ; 14(3): 2370-2390, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38545083

RESUMO

Background: Dual-energy computed tomography (CT) can provide a range of image information beyond conventional CT through virtual monoenergetic images (VMIs). The purpose of this study was to investigate the impact of material decomposition in detector-based spectral CT on radiomics features and effectiveness of using deep learning-based image synthesis to improve the reproducibility of radiomics features. Methods: In this paper, spectral CT image data from 45 esophageal cancer patients were collected for investigation retrospectively. First, we computed the correlation coefficient of radiomics features between conventional kilovoltage peak (kVp) CT images and VMI. Then, a wavelet loss-enhanced CycleGAN (WLL-CycleGAN) with paired loss terms was developed to synthesize virtual monoenergetic CT images from the corresponding conventional single-energy CT (SECT) images for improving radiomics reproducibility. Finally, the radiomic features in 6 different categories, including gray-level co-occurrence matrix (GLCM), gray-level difference matrix (GLDM), gray-level run-length matrix (GLRLM), gray-level size-zone matrix (GLSZM), neighborhood gray-tone difference matrix (NGTDM), and wavelet, were extracted from the gross tumor volumes from conventional single energy CT, synthetic virtual monoenergetic CT images, and virtual monoenergetic CT images. Comparison between errors in the VMI and synthetic VMI (sVMI) suggested that the performance of our proposed deep learning method improved the radiomic feature accuracy. Results: Material decomposition of dual-layer dual-energy CT (DECT) can substantially influence the reproducibility of the radiomic features, and the degree of impact is feature dependent. The average reduction of radiomics errors for 15 patients in testing sets was 96.9% for first-order, 12.1% for GLCM, 12.9% for GLDM, 15.7% for GLRLM, 50.3% for GLSZM, 53.4% for NGTDM, and 6% for wavelet features. Conclusions: The work revealed that material decomposition has a significant effect on the radiomic feature values. The deep learning-based method reduced the influence of material decomposition in VMIs and might improve the robustness and reproducibility of radiomic features in esophageal cancer. Quantitative results demonstrated that our proposed wavelet loss-enhanced paired CycleGAN outperforms the original CycleGAN.

14.
Int J Surg ; 110(6): 3440-3449, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38498405

RESUMO

BACKGROUND: Describe the accurate locations of lymph node recurrence (LNR) of Chinese patients with postoperative thoracic esophageal squamous cell carcinoma (ESCC) is essential for determining the need for further surveillance protocols and treatments. The authors aimed to evaluate the patterns of postoperative ESCC and its current risk stratification with LNR. METHODS: This population-based cohort study included a retrospective review of the medical records and image material of patients with ESCC who underwent LNR after radical surgery between January 2013 and September 2022, with a median follow-up time of 5.71 years. Clinical features were extracted from these records, and survival analysis was performed. The primary endpoint was the accurate location and range of LNR according to the nomenclature of the Japanese Society for Esophageal Diseases. The second endpoints was to explore the related factors of recurrence range and overall survival. RESULTS: A total of 3268 lymph node regions were recurrence from 1129 patients, with a mean of 2.89 regions per patient. No.104, 106, and 107 was the most common recurrence of thoracic ESCC with an LNR rate higher than 15%. In upper thoracic ESCC, No.105 was a common recurrence site and abdominal LNR was rare. In lower thoracic ESCC, retroperitoneal lymph node was a unique regions (15.4%). Anastomotic recurrence is an important recurrence pattern in patients with postoperative esophageal cancer, with an incidence of 24.5%. Rates of LNR in range of lymph node dissection was low (13.9%). The median time of LRT was 20.0 (1.5-184.0) months. High range of recurrence was associated with significantly poorer OS in patients. Multiple linear regression analysis identified demonstrated N stage, tumor differentiation, adjuvant radiotherapy, and total lymph nodes removed were association with recurrence range for patients. CONCLUSIONS: Supraclavicular and upper mediastinums lymph nodes were common recurrence site for ESCC patients, and careful initial staging and surveillance are needed. Thorough lymph node dissection may reduce the range of regional recurrence.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Esofagectomia , Linfonodos , Metástase Linfática , Recidiva Local de Neoplasia , Humanos , Estudos Retrospectivos , Masculino , Feminino , Pessoa de Meia-Idade , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/cirurgia , Neoplasias Esofágicas/mortalidade , Carcinoma de Células Escamosas do Esôfago/cirurgia , Carcinoma de Células Escamosas do Esôfago/patologia , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/epidemiologia , Idoso , Linfonodos/patologia , Linfonodos/cirurgia , Excisão de Linfonodo , Adulto , China/epidemiologia
15.
Int J Radiat Oncol Biol Phys ; 119(3): 896-901, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38181839

RESUMO

PURPOSE: Neoadjuvant chemoradiotherapy is the recommended treatment for patients with resectable esophageal cancer but is associated with a higher incidence of adverse effects. Given the efficacy of immunotherapy, we propose a chemotherapy-free regimen of neoadjuvant radio-immunotherapy (NRIT) to balance therapeutic efficacy and potential side effects or overtreatment. METHODS AND MATERIALS: In this phase 1b clinical trial, we assessed the safety and efficacy of NRIT in esophageal squamous cell cancer. The enrolled patients received 41.4 Gy of radiation and 4 cycles of 240 mg of toripalimab injection before surgery. The primary endpoint was treatment-related adverse events and the secondary endpoints were pathologic complete response and major pathologic response. Immunohistochemistry and multiplex immunofluorescence staining were used to evaluate the tumor microenvironment before and after neoadjuvant treatment. RESULTS: Of the 22 patients enrolled, 19 underwent R0 surgery. One patient discontinued neoadjuvant immune therapy due to experiencing a grade 3 treatment-related adverse event. Three patients did not undergo surgery due to tumor progression or side effects. Among the patients who underwent surgery, 3 patients experienced serious complications shortly after surgery. Upon pathologic evaluation, the pathologic complete response and major pathologic response rates were 47.4% and 68.4%, respectively. CONCLUSIONS: The NRIT regimen is safe and feasible for patients with esophageal squamous cell cancer.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Terapia Neoadjuvante , Humanos , Terapia Neoadjuvante/efeitos adversos , Masculino , Pessoa de Meia-Idade , Neoplasias Esofágicas/terapia , Neoplasias Esofágicas/patologia , Feminino , Idoso , Carcinoma de Células Escamosas do Esôfago/terapia , Carcinoma de Células Escamosas do Esôfago/patologia , Imunoterapia/efeitos adversos , Microambiente Tumoral , Adulto , Resultado do Tratamento , Anticorpos Monoclonais Humanizados/uso terapêutico
16.
Comput Biol Med ; 170: 107983, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38286104

RESUMO

Magnetic resonance (MR) image-guided radiotherapy is widely used in the treatment planning of malignant tumors, and MR-only radiotherapy, a representative of this technique, requires synthetic computed tomography (sCT) images for effective radiotherapy planning. Convolutional neural networks (CNN) have shown remarkable performance in generating sCT images. However, CNN-based models tend to synthesize more low-frequency components and the pixel-wise loss function usually used to optimize the model can result in blurred images. To address these problems, a frequency attention conditional generative adversarial network (FACGAN) is proposed in this paper. Specifically, a frequency cycle generative model (FCGM) is designed to enhance the inter-mapping between MR and CT and extract more rich tissue structure information. Additionally, a residual frequency channel attention (RFCA) module is proposed and incorporated into the generator to enhance its ability in perceiving the high-frequency image features. Finally, high-frequency loss (HFL) and cycle consistency high-frequency loss (CHFL) are added to the objective function to optimize the model training. The effectiveness of the proposed model is validated on pelvic and brain datasets and compared with state-of-the-art deep learning models. The results show that FACGAN produces higher-quality sCT images while retaining clearer and richer high-frequency texture information.


Assuntos
Processamento de Imagem Assistida por Computador , Tomografia Computadorizada por Raios X , Processamento de Imagem Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Redes Neurais de Computação , Imageamento por Ressonância Magnética/métodos , Planejamento da Radioterapia Assistida por Computador/métodos
17.
Technol Cancer Res Treat ; 23: 15330338241227291, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38258381

RESUMO

Purpose: Magnetic resonance (MR)-guided radiotherapy enables visualization of static anatomy, capturing tumor motion, and extracting quantitative image features for treatment verification and outcome monitoring. However, magnetic fields in online MR imaging (MRI) require efforts to ensure accurate dose measurements. This study aimed to assess the dosimetric impact of a 1.5 T magnetic field in esophageal cancer radiotherapy using MR-linac, exploring treatment adaptation potential and personalized medicine benefits. Methods: A prospective cohort study enrolled 100 esophageal squamous cell carcinoma patients undergoing 4DCT and 3DCT scans before radiotherapy. The heart was contoured on 3DCT, 4DCT end expiration (EE), and 4DCT end inhalation (EI) images by the same radiation oncologist. Reference RT plans were designed on 3DCT, with adjustments for different phases generating 5 plan types per patient. Variations in dose-volume parameters for organs at risk and the target area among different plans were compared using Monaco 5.40.04. Results: Slight dose distortions at air-tissue interfaces were observed in the magnetic field's presence. Dose at air-tissue interfaces (chest wall and heart wall) was slightly higher in some patients (3.0% tissue increased by 4.3 Gy on average) compared to nonmagnetic conditions. Average clinical target volume coverage V100 dropped from 99% to 95% compared to reference plans (planEI and planEE). Dose-volume histogram variation between the original plan and reference plans was within 2.3%. Superior-inferior (SI) direction displacement was significantly larger than lateral and anterior-posterior directions (P < .05). Conclusion: Significant SI direction shift in lower esophageal cancerous regions during RT indicates the magnetic field's dosimetric impact, including the electron return effect at tissue-air boundaries. Changes in OAR dose could serve as valuable indicators of organ impairment and target dose alterations, especially for cardiac tissue when using the 1.5 T linac method. Reoptimizing the plan with the magnetic field enhances the feasibility of achieving a clinically acceptable treatment plan for esophageal cancer patients.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Radioterapia (Especialidade) , Humanos , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/radioterapia , Estudos Prospectivos , Campos Magnéticos
19.
Int J Periodontics Restorative Dent ; 0(0): 1-27, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38198438

RESUMO

STATEMENT OF PROBLEM: Volumetric resorption of the alveolar ridge often occurs following tooth extraction in both horizontal and vertical directions. There is a specific lack of evidence for alveolar ridge reconstruction at molar and premolar sites with severe bone resorption. PURPOSE: This randomized and controlled trial aimed to use three dimensional and linear analyses to evaluate volumetric changes of the alveolar bone following alveolar ridge reconstruction (ARR) at molar and premolar sites with severe bone resorption as compared with non-assisted socket healing be implant placement. MATERIAL AND METHODS: A total of 31 patients (15 males and 16 females) with more than 50% of hard tissue loss in one or more socket walls were recruited and randomized into either a test group (ARR after extraction using deproteinized bovine bone mineral with 10% collagen (DBBM-C) and platelet-rich fibrin (PRF) with a resorbable collagen membrane) or a control group (natural healing after extraction). Then, the clinical, linear, volumetric implant-related and patient-reported outcomes were analyzed after a 4-month healing process. RESULTS: Linear bone assessments revealed significantly greater gains of ridge width in the test group (25% in the mesial, mid-facial and distal aspects) and less reduction of vertical bone ridge than in the control group (P<0.05). Furthermore, volumetric bone remodeling was significantly higher in the test group (ARR=35.1±34.9%, control=14.2±12.8%, P<0.05). Patient-reported discomfort and keratinized mucosal changes were comparable between groups. CONCLUSIONS: Alveolar ridge reconstruction with a combination of DBBM-C, PRF, and a resorbable membrane at posterior sites with severe socket wall deficiency (> 50% bone loss) is a safe and more capable therapeutic method when compared with natural healing and non-assisted sockets. CLINICAL IMPLICATIONS: Collectively, our analyses demonstrated that alveolar ridge reconstruction represents an efficient method to maintain and augment crestal bone at posterior extraction sites with severe bone defects when assessed after four months of healing.

20.
Int J Surg ; 110(2): 956-964, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37995095

RESUMO

BACKGROUND: There is no standard management for small cell esophageal carcinoma (SCEC). The purpose of this multicenter, retrospective study (ChiSCER) was to investigate the treatment, outcomes, and risk factors impacting survival endpoints in patients with limited-stage SCEC (LS-SCEC). MATERIALS AND METHODS: Consecutive patients with LS-SCEC from 14 institutions between 2000 and 2020 in China were enrolled. Survival curves were constructed using the Kaplan-Meier method and compared using a log-rank test. Univariate and multivariate Cox regression models and propensity score matching (PSM) analysis were adopted in the prognostic analysis. Results were reported as hazard ratio (HR), 95% confidence interval (CI), and P value. Statistical significance was set as P value <0.05 in a two-tailed test. RESULTS: Among 458 LS-SCEC patients, the median age was 63 [interquartile range (IQR), 57-68] years, and 318 (69%) were males. Eighty-four (18%), 167 (36%), and 207 (45%) patients received chemotherapy (CT) alone, CT plus definitive radiotherapy (CT+RT), and CT plus radical surgery (CT+S), respectively. With a median follow-up time of 58.7 (95% CI 48.9-68.6) months, the median overall survival (OS) and 3-year OS rate for all patients 24.3 (95% CI 21.6-27) months and 37.3% (95% CI 32.8-42.5%), respectively. Multivariate analysis indicated that treatment modes, Karnofsky performance status (KPS), TNM stage, and CT cycle were independent prognostic factors for OS ( P <0.05). Compared with CT alone, patients treated with CT+RT (HR 0.57, 95% CI 0.41-0.8, P =0.001) or CT+S (HR 0.59, 95% CI 0.42-0.82, P =0.002) had an improved OS, with no significant survival differences between CT+S and CT+RT groups after multivariate and PSM analyses ( P >0.05). Subgroup analysis indicated that compared with CT+RT, patients with tumor location at lower 1/3 (HR 0.59, 95% CI 0.37-0.93, P =0.03) or tumor length >5 cm (HR 0.52, 95% CI 0.3-0.9, P =0.02) could obtain significant OS benefit from CT+S. Patients with tumor location at middle 1/3 (HR 1.55, 95% CI 1.03-2.36, P =0.04) or tumor length ≤5 cm (HR 1.49, 95% CI 1.02-2.17, P =0.04) favored CT+RT. Distant metastasis accounted for 73.7% of all treatment failures after multidisciplinary treatments. CONCLUSION: Surgery and RT were equally effective local therapies for patients with LS-SCEC. The personalized decision of local therapy should be made after comprehensive considerations on tumor location, length, comorbidities, and organ preservation.


Assuntos
Carcinoma de Células Pequenas , Neoplasias Esofágicas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma de Células Pequenas/patologia , Estudos de Coortes , Neoplasias Esofágicas/radioterapia , Neoplasias Esofágicas/cirurgia , Neoplasias Esofágicas/tratamento farmacológico , Prognóstico , Estudos Retrospectivos
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