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1.
Chin J Cancer Res ; 36(1): 17-24, 2024 Feb 29.
Article de Anglais | MEDLINE | ID: mdl-38455371

RÉSUMÉ

The prevalence of colorectal cancer (CRC) is increasing annually and metastasis is the principal cause of death in patients with CRC, with the liver being the most frequently affected site. Many studies have shown a strong interplay between the gut flora, particularly Fusobacterium nucleatum (F. nucleatum), Escherichia coli, and Bacteroides fragilis, and the development of gut tumors. Some strains can induce gut inflammation and produce toxins that directly harm gut epithelial cells, ultimately accelerating the onset and progression of CRC. However, little clinical evidence exists on the specific interplay between the gut microflora and colorectal cancer liver metastasis (CRLM). Some research showed the existence of viable F. nucleatum in distant metastasis of CRC. Subsequently, gut microbiota products, such as lipopolysaccharides, sodium butyrate, and protein cathepsin K, were also found to affect the development of CRC. This article summarizes the mechanism and research status of the interplay between gut microflora and CRLM, discusses the importance of gut microflora in the treatment of CRLM, and proposes a new approach to understanding the mechanism of CRLM and potential treatments for the microbiome. It is anticipated that the gut microbiota will be a formidable therapeutic and prophylactic tool for treating and preventing CRLM.

2.
Plants (Basel) ; 13(1)2024 Jan 04.
Article de Anglais | MEDLINE | ID: mdl-38202447

RÉSUMÉ

Nitrogen is a fundamental component for building amino acids and proteins, playing a crucial role in the growth and development of plants. Leaf nitrogen concentration (LNC) serves as a key indicator for assessing plant growth and development. Monitoring LNC provides insights into the absorption and utilization of nitrogen from the soil, offering valuable information for rational nutrient management. This, in turn, contributes to optimizing nutrient supply, enhancing crop yields, and minimizing adverse environmental impacts. Efficient and non-destructive estimation of crop LNC is of paramount importance for on-field crop management. Spectral technology, with its advantages of repeatability and high-throughput observations, provides a feasible method for obtaining LNC data. This study explores the responsiveness of spectral parameters to soybean LNC at different vertical scales, aiming to refine nitrogen management in soybeans. This research collected hyperspectral reflectance data and LNC data from different leaf layers of soybeans. Three types of spectral parameters, nitrogen-sensitive empirical spectral indices, randomly combined dual-band spectral indices, and "three-edge" parameters, were calculated. Four optimal spectral index selection strategies were constructed based on the correlation coefficients between the spectral parameters and LNC for each leaf layer. These strategies included empirical spectral index combinations (Combination 1), randomly combined dual-band spectral index combinations (Combination 2), "three-edge" parameter combinations (Combination 3), and a mixed combination (Combination 4). Subsequently, these four combinations were used as input variables to build LNC estimation models for soybeans at different vertical scales using partial least squares regression (PLSR), random forest (RF), and a backpropagation neural network (BPNN). The results demonstrated that the correlation coefficients between the LNC and spectral parameters reached the highest values in the upper soybean leaves, with most parameters showing significant correlations with the LNC (p < 0.05). Notably, the reciprocal difference index (VI6) exhibited the highest correlation with the upper-layer LNC at 0.732, with a wavelength combination of 841 nm and 842 nm. In constructing the LNC estimation models for soybeans at different leaf layers, the accuracy of the models gradually improved with the increasing height of the soybean plants. The upper layer exhibited the best estimation performance, with a validation set coefficient of determination (R2) that was higher by 9.9% to 16.0% compared to other layers. RF demonstrated the highest accuracy in estimating the upper-layer LNC, with a validation set R2 higher by 6.2% to 8.8% compared to other models. The RMSE was lower by 2.1% to 7.0%, and the MRE was lower by 4.7% to 5.6% compared to other models. Among different input combinations, Combination 4 achieved the highest accuracy, with a validation set R2 higher by 2.3% to 13.7%. In conclusion, by employing Combination 4 as the input, the RF model achieved the optimal estimation results for the upper-layer LNC, with a validation set R2 of 0.856, RMSE of 0.551, and MRE of 10.405%. The findings of this study provide technical support for remote sensing monitoring of soybean LNCs at different spatial scales.

3.
Adv Sci (Weinh) ; 11(6): e2306740, 2024 Feb.
Article de Anglais | MEDLINE | ID: mdl-38054649

RÉSUMÉ

Ion doping is an effective strategy for achieving high-performance flexible Cu2 ZnSn(S,Se)4 (CZTSSe) solar cells by defect regulations. Here, a Li&Na co-doped strategy is applied to synergistically regulate defects in CZTSSe bulks. The quality absorbers with the uniformly distributed Li and Na elements are obtained using the solution method, where the acetates (LiAc and NaAc) are as additives. The concentration of the harmful CuZn anti-site defects is decreased by 8.13% after Li incorporation, and that of the benign NaZn defects is increased by 36.91% after Na incorporation. Synergistic Li&Na co-doping enhances the carrier concentration and reduces the interfacial defects concentration by one order of magnitude. As a result, the flexible CZTSSe solar cell achieves a power conversion efficiency (PCE) of 10.53% with certified 10.12%. Because of the high PCE and the homogeneous property, the Li&Na co-doped device is fabricated to a large area (2.38 cm2 ) and obtains 9.41% PCE. The co-doping investigation to synergistically regulate defects provides a new perspective for efficient flexible CZTSSe solar cells.

4.
Biol Pharm Bull ; 46(12): 1706-1713, 2023 Dec 02.
Article de Anglais | MEDLINE | ID: mdl-37778980

RÉSUMÉ

Inflammatory bowel disease (IBD) is a worldwide issue, and the increased incidence has brought a heavy burden to patients and society. Gut microbiota is involved in the pathogenesis of IBD, and targeting the microbiota, such as probiotics, has emerged as a potential therapy for the treatment of IBD. Here, the effect of Bifidobacterium animalis ssp. lactis LKM512 (LKM512), an anti-aging probiotic, on dextran sulfate sodium salt (DSS)-induced IBD in larval zebrafish was determined. Supplementation of LKM512 promoted the survival rate of the larvae, together with increased locomotor activities and body length. In addition, LKM512 treatment enhanced mucus secretion and alleviated intestinal injury, and these results were associated with the upregulation of mucin-related and downregulation of inflammatory markers. Moreover, LKM512 increased the diversity of the microbiota and ameliorated the dysbiosis by increasing the abundance of Bacteroidetes and Firmicutes and reducing the abundance of Proteobacteria. Specifically, the abundance of beneficial bacteria, including the short-chain fatty-acids (SCFAs)-producing genera Lachnospiraceae_NK4A136_group, Muribaculaceae, and Alloprevotella, was increased by LKM512, while the abundance of harmful genera, such as Pseudomonas, Halomonas, and Escherichia-Shigella, was reduced by LKM512. Consistent with these findings, the microbial functions related to metabolism were partly reversed by LKM512, and importantly, fermentation of short-chain fatty acids-related functions were enhanced by LKM512. Therefore, LKM512 might be one potential probiotic for the prevention and treatment of IBD, and further studies that clarify the mechanism of LKM512 would promote the application of LKM512.


Sujet(s)
Bifidobacterium animalis , Maladies inflammatoires intestinales , Microbiote , Animaux , Humains , Danio zébré , Bifidobacterium/métabolisme , Fèces/microbiologie , Maladies inflammatoires intestinales/traitement médicamenteux , Sulfate dextran
5.
Int J Radiat Oncol Biol Phys ; 117(5): 1255-1269, 2023 Dec 01.
Article de Anglais | MEDLINE | ID: mdl-37433373

RÉSUMÉ

PURPOSE: To assess taxonomic and functional characteristics of tumor-bearing microbiota and its association with response to neoadjuvant chemoradiation therapy (nCRT) in patients with locally advanced rectal cancer. METHODS AND MATERIALS: We performed metagenomic sequencing of biopsy tumoral tissues from 73 patients with locally advanced rectal cancer before nCRT. Patients were classified into poor responders (PR) and good responders (GR) according to response to nCRT. Subsequent investigation of network alteration, key community, microbial biomarkers, and function related to nCRT responses were carried out. RESULTS: The network-driven analysis systematically revealed 2 co-occurring bacteria modules that exhibited opposite relationship with rectal cancer radiosensitivity. In the 2 modules, prominent alteration of global graph properties and community structure was observed between networks of PR and GR group. By quantifying changes in between-group association patterns and abundances, a total of 115 discriminative biomarker species linked to nCRT response were found, and 35 microbial variables were selected to establish the optimal randomForest classifier for nCRT response prediction. It yielded an area under the curve value of 85.5% (95% CI, 73.3%-97.8%) in the training cohort and 88.4% (95% CI, 77.5%-99.4%) in the validation cohort. In a comprehensive consideration, 5 key bacteria showed high relevance with inducing resistance to nCRT, including Streptococcus equinus, Schaalia odontolytica, Clostridium hylemonae, Blautia producta, and Pseudomonas azotoformans. One key hub including several butyrate-formation bacteria involving with driving network alteration from GR to PR indicate that microbiota-derived butyrate may also be involved in reducing the antitumor effects of nCRT, especially Coprococcus. The functional analysis of metagenome linked the nitrate and sulfate-sulfur assimilation, histidine catabolic process, and resistance to cephamycin to the reduced therapeutic response. It also linked to leucine degradation, isoleucine biosynthesis, taurine, and hypotaurine metabolism to the improved response to nCRT. CONCLUSIONS: Our data offer novel potential microbial factors and shared metagenome function linked to resistance to nCRT.


Sujet(s)
Microbiote , Tumeurs du rectum , Humains , Traitement néoadjuvant , Métagénome , Chimioradiothérapie/méthodes , Tumeurs du rectum/anatomopathologie , Marqueurs biologiques , Butyrates , Résultat thérapeutique
6.
Materials (Basel) ; 16(7)2023 Apr 04.
Article de Anglais | MEDLINE | ID: mdl-37049163

RÉSUMÉ

Flexible CZTSSe solar cells have attracted much attention due to their earth-abundant elements, high stability, and wide application prospects. However, the environmental problems caused by the high toxicity of the Cd in the buffer layers restrict the development of flexible CZTSSe solar cells. Herein, we develop a Cd-free flexible CZTSSe/ZnO solar cell. The influences of the ZnO films on device performances are investigated. The light absorption capacity of flexible CZTSSe solar cells is enhanced due to the removal of the CdS layer. The optimal thickness of the ZnO buffer layers and the appropriate annealing temperature of the CZTSSe/ZnO are 100 nm and 200 °C. Ultimately, the optimum flexible CZTSSe/ZnO device achieves an efficiency of 5.0%, which is the highest efficiency for flexible CZTSSe/ZnO solar cells. The systematic characterizations indicate that the flexible CZTSSe/ZnO solar cells based on the optimal conditions achieved quality heterojunction, low defect density and better charge transfer capability. This work provides a new strategy for the development of the environmentally friendly and low-cost flexible CZTSSe solar cells.

7.
Small ; 18(22): e2201347, 2022 Jun.
Article de Anglais | MEDLINE | ID: mdl-35510960

RÉSUMÉ

Flexible Cu2 ZnSn(S,Se)4 (CZTSSe) solar cells show great potential due to non-toxicity and low cost. The quality of CZTSSe absorber suffering from the high-temperature selenization process is the key to overcoming open-circuit voltage (VOC ) deficit and obtaining high efficiency. In this work, the authors develop a selenization technique to improve the quality of the CZTSSe layer by pre-evaporation selenization. This method provides saturated selenium vapor at the beginning of the selenization process to promote the crystallization process. The oversaturated selenium source greatly shortens the annealing time at high temperatures. The prepared CZTSSe films have larger grains and fewer voids. The measurement of the space charge limited current shows that the defect density of the CZTSSe absorber is significantly reduced from 4.43 × 1013  cm-3 to 3.46 × 1013 cm-3 . Electrical tests show that the devices have better charge separation at the interface, resulting in a charge recombination lifetime, increasing from 133 to 197 µs. The power conversion efficiency of the flexible CZTSSe solar cell reaches 10.24% with VOC and the fill factor enhances to 463 mV and 62%, respectively. The safe non-toxicity and efficient selenization method is expected to provide a new strategy for high-efficiency flexible CZTSSe solar cells.

8.
Cancer Med ; 11(1): 117-127, 2022 01.
Article de Anglais | MEDLINE | ID: mdl-34816622

RÉSUMÉ

BACKGROUND: Anal squamous cell carcinoma (ASCC) is a rare malignant tumor with increasing incidence. The goal of our study was to analyze the treatment outcome and prognostic factors of ASCC in South China in the past half-century. METHODS: This study retrospectively included 59 patients with ASCC admitted from 1975 to 2018 in Sun Yat-sen University cancer center. The clinical records and follow-up information of all patients were collected. Survival analysis and univariate and multivariate regression analyses were performed using the "survival" and "survminer" packages of R software. RESULTS: In 59 patients, 5 patients had distant metastasis at diagnosis. Among 54 M0 stage patients, 33 patients received chemoradiotherapy (CRT), 19 patients received local surgery, and 2 patients refused curative treatment and received the best supportive treatment (BST). The most common grade 3-4 acute toxicities during treatment were myelosuppression and radiation dermatitis. The median follow-up time was 32 months. For the whole group, the 3-year and 5-year overall survival (OS) rates and disease-free survival (DFS) were 71.1% and 63.6%, and 73.4% and 69.0%, respectively. Multivariate regression analysis showed that the T3-4 stage was an independent prognostic risk factor for OS, progression-free survival (PFS), and DFS. And M1 was an independent prognostic risk factor for PFS and DFS. Patients in stage M0 mainly treated with CRT had better local control than those mainly treated with surgery (p = 0.027). For M0 patients, induction chemotherapy combined with CRT tends to prolong OS compared with CRT alone (p = 0.26). The 3-year colostomy-free survival for the whole group was 81.1%. CONCLUSIONS: CRT is recommended as the first choice for the treatment of M0 stage ASCC. Induction chemotherapy may bring better survival benefits for some patients. Patients with ASCC in China seem to have a better local control rate, which suggested different treatment strategies may be needed in China.


Sujet(s)
Tumeurs de l'anus/thérapie , Carcinome épidermoïde/thérapie , Adolescent , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Tumeurs de l'anus/mortalité , Tumeurs de l'anus/anatomopathologie , Tumeurs de l'anus/chirurgie , Maladies de la moelle osseuse/étiologie , Carcinome épidermoïde/mortalité , Carcinome épidermoïde/anatomopathologie , Carcinome épidermoïde/chirurgie , Chimioradiothérapie/effets indésirables , Chine/épidémiologie , Femelle , Études de suivi , Humains , Chimiothérapie d'induction/effets indésirables , Mâle , Adulte d'âge moyen , Métastase tumorale , Stadification tumorale , Radiodermite/étiologie , Études rétrospectives , Analyse de survie , Centres de soins tertiaires , Résultat thérapeutique , Jeune adulte
9.
BMC Cancer ; 21(1): 1333, 2021 Dec 14.
Article de Anglais | MEDLINE | ID: mdl-34906114

RÉSUMÉ

BACKGROUND: The optimal treatment of stage IV rectal cancer remains controversial. The purpose of this study was to assess the treatment outcomes and toxicity of neoadjuvant chemotherapy and radiotherapy followed by local treatment of all tumor sites and subsequent adjuvant chemotherapy in stage IV rectal cancer patients with potentially resectable metastases. METHODS: Adult patients diagnosed with locally advanced rectal adenocarcinoma with potentially resectable metastases, who received neoadjuvant chemotherapy and radiotherapy from July 2013 and September 2019 at Sun Yat-sen University cancer center, were included. Completion of the whole treatment schedule, pathological response, treatment-related toxicity and survival were evaluated. RESULTS: A total of 228 patients were analyzed with a median follow-up of 33 (range 3.3 to 93.4) months. Eventually, 112 (49.1%) patients finished the whole treatment schedule, of which complete response of all tumor sites and pathological downstaging of the rectal tumor were observed in three (2.7%) and 90 (80.4%) patients. The three-year overall survival (OS) and progression-free survival (PFS) of all patients were 56.6% (50.2 to 63.9%) and 38.6% (95% CI 32.5 to 45.8%), respectively. For patients who finished the treatment schedule, 3-year OS (74.4% vs 39.2%, P < 0.001) and 3-year PFS (45.5% vs 30.5%, P = 0.004) were significantly improved compared those who did not finish the treatment. Grade 3-4 chem-radiotherapy treatment toxicities were observed in 51 (22.4%) of all patients and surgical complications occurred in 22 (9.6%) of 142 patients who underwent surgery, respectively. CONCLUSIONS: Neoadjuvant chemotherapy and radiotherapy followed by resection/ablation and subsequent adjuvant chemotherapy offered chances of long-term survival with tolerable toxicities for selected patients with potentially resectable stage IV rectal cancer, and could be considered as an option in clinical practice.


Sujet(s)
Techniques d'ablation/mortalité , Adénocarcinome/thérapie , Traitement néoadjuvant/mortalité , Proctectomie/mortalité , Tumeurs du rectum/thérapie , Adénocarcinome/mortalité , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Protocoles antinéoplasiques , Traitement médicamenteux adjuvant/méthodes , Traitement médicamenteux adjuvant/mortalité , Association thérapeutique , Femelle , Études de suivi , Humains , Mâle , Adulte d'âge moyen , Traitement néoadjuvant/méthodes , Stadification tumorale , Survie sans progression , Radiothérapie adjuvante/méthodes , Radiothérapie adjuvante/mortalité , Tumeurs du rectum/mortalité , Induction de rémission , Études rétrospectives , Taux de survie , Résultat thérapeutique
11.
BMC Cancer ; 21(1): 479, 2021 Apr 30.
Article de Anglais | MEDLINE | ID: mdl-33931024

RÉSUMÉ

BACKGROUND: Ubiquitin-conjugating enzyme E2W (UBE2W) is a protein-coding gene that has an important role in ubiquitination and may be vital in the repair of DNA damage. However, studies on the prognostic value of UBE2W and its correlation with tumor-infiltrating immune cells in multiple cancers have not been addressed. METHODS: We investigated UBE2W expression in the Oncomine database, the Tumor Immune Estimation Resource (TIMER), TNMplot database. Then, the clinical prognostic value of UBE2W was analyzed via online public databases. Meanwhile, we explored the correlation between UBE2W and DNA repair associate genes expression and DNA methyltransferase expression by TIMER and Gene Expression Profiling Interactive Analysis (GEPIA). By using the same method, the correlation between UBE2W and tumor-infiltrating immune cells was explored. Genomic Profiles of UBE2W in breast cancer (BRCA) were accessed in cBioPortal (v3.5.0). Functional proteins associated network was analyzed by STRING database (v11.0). RESULTS: UBE2W was abnormally expressed and significantly correlated with mismatch repair (MMR) gene mutation levels, DNA methyltransferase, and BRCA1/2 expression in breast cancer. High expression of UBE2W may promote the tumor immunosuppression and metastasis, induce endocrine therapy resistance and deteriorate outcomes of patients with breast cancer. These findings suggest that UBE2W could be a potential biomarker of prognosis and tumor-infiltrating immune cells. Besides, RBX1 may be a new E3 that was regulated by UBE2W. CONCLUSIONS: Ubiquitin E2 UBE2W is a potential prognostic biomarker and is correlated with immune infiltration in BRCA.


Sujet(s)
Tumeurs du sein/immunologie , Tumeurs du sein/métabolisme , Réparation de mésappariement de l'ADN/génétique , Lymphocytes TIL , Ubiquitin-conjugating enzymes/métabolisme , Tumeurs du sein/mortalité , Bases de données factuelles , Femelle , Expression des gènes , Analyse de profil d'expression de gènes , Gène BRCA1 , Gène BRCA2 , Humains , Methyltransferases/métabolisme , Mutation , Tumeurs/métabolisme , Pronostic , Microenvironnement tumoral/immunologie , Ubiquitin-conjugating enzymes/génétique , Ubiquitination
12.
Radiat Oncol ; 16(1): 93, 2021 May 24.
Article de Anglais | MEDLINE | ID: mdl-34030722

RÉSUMÉ

BACKGROUND: Patients with locally advanced sigmoid colon cancer (LASCC) have limited treatment options and a dismal prognosis with poor quality of life. This retrospective study aimed to further evaluate the feasibility and efficacy of neoadjuvant chemoradiotherapy (NACRT) followed by surgery as treatment for select patients with unresectable LASCC. METHODS: We studied patients with unresectable LASCC who received NACRT between November 2010 and April 2019. The NACRT regimen consisted of intensity modulated radiotherapy (IMRT) of 50 Gy to the gross tumor and positive lymphoma node and 45 Gy to the clinical target volume. Capecitabine­based chemotherapy was administered every 2 (mFOLFOX6) or 3 weeks (CAPEOX). Surgery was scheduled 6-8 weeks after radiotherapy. RESULTS: Seventy­two patients were enrolled in this study. Patients had a regular follow-up (median, 41.1 months; range, 8.3-116.5 months). Seventy­one patients completed NACRT, and sixty-five completed surgery. Resection with microscopically negative margins (R0 resection) was achieved in 64 patients (88.9%). Pathologic complete response was observed in 15 patients (23.1%), and multivisceral resection was necessary in 38 patients (58.3%). The cumulative probability of 3-year overall survival (OS) and progression-free survival (PFS) were 75.8 and 70.7%, respectively. CONCLUSIONS: For patients with unresectable LASCC, neoadjuvant chemoradiotherapy is feasible, surgery can be performed safely and may result in increased survival and organ preservation rates.


Sujet(s)
Chimioradiothérapie , Traitement néoadjuvant , Tumeurs du sigmoïde/thérapie , Adulte , Sujet âgé , Protocoles de polychimiothérapie antinéoplasique/usage thérapeutique , Capécitabine/usage thérapeutique , Colectomie , Femelle , Humains , Irradiation ganglionnaire , Métastase lymphatique , Mâle , Adulte d'âge moyen , Traitements préservant les organes , Survie sans progression , Dosimétrie en radiothérapie , Radiothérapie conformationnelle avec modulation d'intensité , Études rétrospectives , Tumeurs du sigmoïde/mortalité , Tumeurs du sigmoïde/anatomopathologie , Tumeurs du sigmoïde/chirurgie , Taux de survie
13.
BMC Cancer ; 21(1): 179, 2021 Feb 19.
Article de Anglais | MEDLINE | ID: mdl-33607964

RÉSUMÉ

BACKGROUND: The management of unresectable locally advanced colon cancer (LACC) remains controversial, as resection is not feasible. The goal of this study was to evaluate the treatment outcomes and toxicity of neoadjuvant chemoradiotherapy (NACRT) followed with surgery and adjuvant chemotherapy in patients with unresectable radically LACC. METHODS: We included patients who were diagnosed at our institution, 2010-2018. The neoadjuvant regimen consisted of radiotherapy and capecitabine/ 5-fluorouracil-based chemotherapy. RESULTS: One hundred patients were identified. The median follow-up time was 32 months. The R0 resection rate, adjusted nonmultivisceral resection rate and bladder preservation rate were 83.0, 43.0 and 83.3%, respectively. The pCR and clinical-downstaging rates were 18, and 81.0%%, respectively. The 3-year PFS and OS rates for all patients were 68.6 and 82.1%, respectively. Seventeen patients developed grade 3-4 myelosuppression, which was the most common adverse event observed after NACRT. Tumor perforation occurred in 3 patients during NACRT. The incidence of grade 3-4 surgery-related complications was 7.0%. Postoperative anastomotic leakage was observed in 3 patients. CONCLUSIONS: NACRT followed by surgery was feasible and safe for selected patients with LACC, and can be used as a conversion treatment to achieve satisfactory downstaging, long-term survival and quality of life, with acceptable toxicities.


Sujet(s)
Protocoles de polychimiothérapie antinéoplasique/usage thérapeutique , Tumeurs du côlon/thérapie , Sujet âgé , Protocoles de polychimiothérapie antinéoplasique/effets indésirables , Capécitabine/administration et posologie , Capécitabine/effets indésirables , Traitement médicamenteux adjuvant , Tumeurs du côlon/mortalité , Tumeurs du côlon/anatomopathologie , Association thérapeutique , Femelle , Fluorouracil/administration et posologie , Fluorouracil/effets indésirables , Humains , Mâle , Adulte d'âge moyen , Traitement néoadjuvant , Stadification tumorale , Qualité de vie , Taux de survie , Résultat thérapeutique
14.
Radiat Oncol ; 16(1): 16, 2021 Jan 19.
Article de Anglais | MEDLINE | ID: mdl-33468176

RÉSUMÉ

BACKGROUND: The watch-and-wait strategy offers a non-invasive therapeutic alternative for rectal cancer patients who have achieved a clinical complete response (cCR) after chemoradiotherapy. This study aimed to investigate the long-term clinical outcomes of this strategy in comparation to surgical resection. METHODS: Stage II/III rectal adenocarcinoma patients who received neoadjuvant chemoradiotherapy and achieved a cCR were selected from the databases of three centers. cCR was evaluated by findings from digital rectal examination, colonoscopy, and radiographic images. Patients in whom the watch-and-wait strategy was adopted were matched with patients who underwent radical resection through 1:1 propensity score matching analyses. Survival was calculated and compared in the two groups using the Kaplan-Meier method with the log rank test. RESULTS: A total of 117 patients in whom the watch-and-wait strategy was adopted were matched with 354 patients who underwent radical resection. After matching, there were 94 patients in each group, and no significant differences in term of age, sex, T stage, N stage or tumor location were observed between the two groups. The median follow-up time was 38.2 months. Patients in whom the watch-and-wait strategy was adopted exhibited a higher rate of local recurrences (14.9% vs. 1.1%), but most (85.7%) were salvageable. Three-year non-regrowth local recurrence-free survival was comparable between the two groups (98% vs. 98%, P = 0.506), but the watch-and-wait group presented an obvious advantage in terms of sphincter preservation, especially in patients with a tumor located within 3 cm of the anal verge (89.7% vs. 41.2%, P < 0.001). Three-year distant metastasis-free survival (88% in the watch-and-wait group vs. 89% in the surgical group, P = 0.874), 3-year disease-specific survival (99% vs. 96%, P = 0.643) and overall survival (99% vs. 96%, P = 0.905) were also comparable between the two groups, although a higher rate (35.7%) of distant metastases was observed in patients who exhibited local regrowth in the watch-and-wait group. CONCLUSION: The watch-and-wait strategy was safe, with similar survival outcomes but a superior sphincter preservation rate as compared to surgery in rectal cancer patients achieving a cCR after neoadjuvant chemoradiotherapy, and could be offered as a promising conservative alternative to invasive radical surgery.


Sujet(s)
Adénocarcinome/chirurgie , Chimioradiothérapie/méthodes , Tumeurs du rectum/chirurgie , Observation (surveillance clinique)/méthodes , Adénocarcinome/mortalité , Sujet âgé , Femelle , Humains , Mâle , Adulte d'âge moyen , Traitement néoadjuvant , Tumeurs du rectum/mortalité , Études rétrospectives
15.
Front Oncol ; 10: 551763, 2020.
Article de Anglais | MEDLINE | ID: mdl-33489869

RÉSUMÉ

BACKGROUND AND PURPOSE: To validate the feasibility and efficiency of a fully automatic knowledge-based planning (KBP) method for nasopharyngeal carcinoma (NPC) cases, with special attention to the possible way that the success rate of auto-planning can be improved. METHODS AND MATERIALS: A knowledge-based dose volume histogram (DVH) prediction model was developed based on 99 formerly treated NPC patients, by means of which the optimization objectives and the corresponding priorities for intensity modulation radiation therapy (IMRT) planning were automatically generated for each head and neck organ at risk (OAR). The automatic KBP method was thus evaluated in 17 new NPC cases with comparison to manual plans (MP) and expert plans (EXP) in terms of target dose coverage, conformity index (CI), homogeneity index (HI), and normal tissue protection. To quantify the plan quality, a metric was applied for plan evaluation. The variation in the plan quality and time consumption among planners was also investigated. RESULTS: With comparable target dose distributions, the KBP method achieved a significant dose reduction in critical organs such as the optic chiasm (p<0.001), optic nerve (p=0.021), and temporal lobe (p<0.001), but failed to spare the spinal cord (p<0.001) compared with MPs and EXPs. The overall plan quality evaluation gave mean scores of 144.59±11.48, 142.71±15.18, and 144.82±15.17, respectively, for KBPs, MPs, and EXPs (p=0.259). A total of 15 out of 17 KBPs (i.e., 88.24%) were approved by our physician as clinically acceptable. CONCLUSION: The automatic KBP method using the DVH prediction model provided a possible way to generate clinically acceptable plans in a short time for NPC patients.

16.
Radiother Oncol ; 136: 98-105, 2019 07.
Article de Anglais | MEDLINE | ID: mdl-31015136

RÉSUMÉ

PURPOSE: To evaluate the outcomes of 45 Gy/15 fractions/once-daily and 45 Gy/30 fractions/twice-daily radiation schemes utilizing intensity-modulated radiation therapy (IMRT) in extensive stage small cell lung cancer (SCLC), and to build up a new radiobiological model for tumor control probability (TCP) considering multiple biological effects. METHODS: Fifty-eight consecutive patients diagnosed with extensive stage SCLC, treated with chemotherapy and chest irradiation, were retrospectively reviewed. Thirty-seven received hyperfractionated IMRT (Hyper-IMRT, 45 Gy/30 fractions/twice-daily) and 21 received hypofractionated IMRT (Hypo-IMRT, 45 Gy/15 fractions/once-daily). Local progression-free survival (LPFS) and overall survival (OS) were calculated and compared. An extended linear-quadratic (LQ) model, LQRG, incorporating cell repair, redistribution, reoxygenation, regrowth and Gompertzian tumor growth was created based on the clinical data. The TCP model was reformulated to predict LPFS. The classical LQ and TCP models were compared with the new models. Akaike information criterion (AIC) was used to assess the quality of the models. RESULTS: The 2-year LPFS (34.1% vs 27.9%, p = 0.44) and OS (76.9% vs 76.9%, p = 0.26) were similar between Hyper- and Hypo-IMRT patients. According to the LQRG model, the α/ß calculated was 9.2 (95% confidence interval: 8.7-9.9) Gy after optimization. The average absolute and relative fitting errors for LPFS were 9.1% and 18.7% for Hyper-IMRT, and 8.8% and 16.2% for Hypo-IMRT of the new TCP model, compared with 29.1% and 62.3% for Hyper-IMRT, and 30.7% and 65.3% for Hypo-IMRT of the classical model. CONCLUSIONS: Hypo- and Hyper-IMRT resulted in comparable local control in the chest irradiation of extensive stage SCLC. The LQRG model has better performance in predicting the TCP (or LPFS) of the two schemes.


Sujet(s)
Fractionnement de la dose d'irradiation , Tumeurs du poumon/radiothérapie , Radiothérapie conformationnelle avec modulation d'intensité/méthodes , Carcinome pulmonaire à petites cellules/radiothérapie , Humains , Modèles linéaires , Tumeurs du poumon/mortalité , Probabilité , Hypofractionnement de dose , Études rétrospectives , Carcinome pulmonaire à petites cellules/mortalité
17.
Oncotarget ; 8(12): 20179-20186, 2017 Mar 21.
Article de Anglais | MEDLINE | ID: mdl-28423624

RÉSUMÉ

OBJECTIVE: To assess the breast dose during a routine thoracic cone-beam CT (CBCT) check with the efforts to explore the possible dose reduction strategy. MATERIALS AND METHODS: Metal oxide semiconductor field-effect transistor (MOSFET) dosimeters were used to measure breast surface doses during a thorax kV CBCT scan in an anthropomorphic phantom. Breast doses for different scanning protocols and breast sizes were compared. Dose reduction was attempted by using partial arc CBCT scan with bowtie filter. The impact of this dose reduction strategy on image registration accuracy was investigated. RESULTS: The average breast surface doses were 20.02 mGy and 11.65 mGy for thoracic CBCT without filtration and with filtration, respectively. This indicates a dose reduction of 41.8% by use of bowtie filter. It was found 220° partial arc scanning significantly reduced the dose to contralateral breast (44.4% lower than ipsilateral breast), while the image registration accuracy was not compromised. CONCLUSIONS: Breast dose reduction can be achieved by using ipsilateral 220° partial arc scan with bowtie filter. This strategy also provides sufficient image quality for thorax image registration in daily patient positioning verification.


Sujet(s)
Région mammaire/imagerie diagnostique , Tomodensitométrie à faisceau conique/méthodes , Organes à risque/effets des radiations , Fantômes en imagerie , Dosimètres , Planification de radiothérapie assistée par ordinateur/méthodes , Tumeurs du sein/imagerie diagnostique , Tumeurs du sein/radiothérapie , Femelle , Humains , Radiographie thoracique , Dosimétrie en radiothérapie
18.
Radiother Oncol ; 121(2): 239-245, 2016 11.
Article de Anglais | MEDLINE | ID: mdl-27793445

RÉSUMÉ

PURPOSE: To explore the value of combined modalities, including anatomical and functional magnetic resonance imaging (MRI), endoscopy and computed tomography (CT), for the assessment of tumor responses to definitive chemoradiotherapy (dCRT) in esophageal squamous cell carcinoma (ESCC). METHODS: Sixty-seven patients with locally advanced ESCC were enrolled. Tumor response (TR) was assessed two months after the completion of dCRT. Evaluation criteria according to combined modalities, including MRI, endoscopy and CT, were established and compared with traditional criteria based on CT and endoscopy. Progression-free survival (PFS)⩾12months was used as the reference standard, and the accuracy of the two criteria in response assessment was analyzed. RESULTS: Thirty-seven (55.2%) and 10 (14.9%) patients were considered to exhibit CR, as assessed by combined modalities and the traditional criteria, respectively. Using PFS⩾12months as a surrogate for CR, the sensitivity and specificity of the combined modalities were 82.4% and 88.9%, respectively, compared with 20.6% and 92.6% for the traditional criteria. TR assessed by combined modalities (CR vs. non-CR) was prognostic of PFS in univariate and multivariate analyses (Log-rank, P<0.0001; Cox regression, HR=0.114, 95% CI 0.048-0.272). CONCLUSIONS: Tumor responses assessed by the combined modalities of MR, endoscopy and CT seemed highly predictive of prognosis after dCRT in ESCC patients.


Sujet(s)
Carcinome épidermoïde/imagerie diagnostique , Carcinome épidermoïde/thérapie , Chimioradiothérapie/méthodes , Tumeurs de l'oesophage/imagerie diagnostique , Tumeurs de l'oesophage/thérapie , Adulte , Sujet âgé , Carcinome épidermoïde/anatomopathologie , Survie sans rechute , Tumeurs de l'oesophage/anatomopathologie , Carcinome épidermoïde de l'oesophage , Oesophagoscopie , Femelle , Humains , Estimation de Kaplan-Meier , Imagerie par résonance magnétique/méthodes , Mâle , Adulte d'âge moyen , Imagerie multimodale/méthodes , Stadification tumorale , Pronostic , Tomodensitométrie/méthodes , Résultat thérapeutique
19.
Sci Rep ; 6: 28280, 2016 06 21.
Article de Anglais | MEDLINE | ID: mdl-27323696

RÉSUMÉ

This retrospective study used a population-based national registry to determine the impact of local treatment modalities on survival in patients with metastatic esophageal cancer (EC). The Surveillance Epidemiology and End Results (SEER) database was used to identify patients with metastatic EC from 1988 to 2012. A total of 9,125 patients were identified. There were 426 patients underwent primary surgery, 4,786 patients were administered radiotherapy (RT) alone, 847 patients underwent surgery plus RT, and 3,066 patients without any local treatment. Multivariate analysis results indicated that year of diagnosis, age, race, histologic subtype, grade, and local treatment modalities were independent prognostic factors for overall survival (OS). The 5-year OS were 8.4%, 4.5%, 17.5%, and 3.4% in primary surgery, RT only, surgery plus RT, and no local treatment, respectively (P < 0.001). Subgroup analyses showed that the impact of RT was mainly reflected by preoperative radiotherapy, as patients received preoperative radiotherapy had significantly better OS than patients who underwent primary surgery alone and postoperative RT, the 5-year OS rates were 24.7%, 6.5%, and 7.8%, respectively, respectively (P < 0.001). Surgery plus RT, especially preoperative RT, may improve long-term survival of patients with metastatic EC.


Sujet(s)
Adénocarcinome/thérapie , Tumeurs de l'oesophage/thérapie , Tumeurs épidermoïdes/thérapie , Adénocarcinome/mortalité , Adénocarcinome/secondaire , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Association thérapeutique , Tumeurs de l'oesophage/mortalité , Tumeurs de l'oesophage/anatomopathologie , Femelle , Humains , Estimation de Kaplan-Meier , Mâle , Adulte d'âge moyen , Analyse multifactorielle , Tumeurs épidermoïdes/mortalité , Tumeurs épidermoïdes/secondaire , Pronostic , Modèles des risques proportionnels , Études rétrospectives , Programme SEER , Résultat thérapeutique , Jeune adulte
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