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Long non-coding RNA (lncRNA) and circular RNA (circRNA) are two important types of non-coding RNA that can regulate gene expression by directly interacting with DNA, RNA or protein. A large number of studies have shown that lncRNA and circRNA can not only predict the prognosis of patients with esophageal squamous cell carcinoma (ESCC) after radiotherapy and chemotherapy, but also affect the sensitivity of ESCC to radiotherapy and chemotherapy through competing endogenous RNA mechanisms, regulating PI3K/Akt/mTOR and Wnt/β-catenin signaling pathways, participating in DNA and protein modification, regulating the cell cycle and other pathways. In-depth research on the mechanism of lncRNA and circRNA regulating the sensitivity of ESCC to radiotherapy and chemotherapy will improve the effect of radiotherapy and chemotherapy in ESCC patients.
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Adjuvant radiotherapy has become an important part of the standard treatment for breast cancer. Compared with the traditional postoperative radiotherapy, neoadjuvant radiotherapy has the theoretical advantages of more accurate target delineation, optimization of radiation strategy for breast reconstruction, increase of breast conservation surgery with tumor down-staging and avoiding breast surgery by improving pathological complete response rate, which have been confirmed by recent clinical research. Prospective studies are still needed for the optimal target delineation, dose fractionation, radiation-surgery interval, and combination with systemic therapies, aiming to provide the optimal treatment option for patients with early breast cancer.
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Neoadjuvant chemoradiotherapy is the preferred treatment mode for the diagnosis and treatment of locally advanced operable esophageal carcinoma recommended by many guidelines. However, some problems remain to be further explored. In this article, current problems perplexing clinical practice were sorted out, aiming to provide constructive suggestions for the smooth development of neoadjuvant chemoradiotherapy for esophageal carcinoma in the future.
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Objective:To explore the effects of clinical characteristics and dosimetric factors on the survival and prognosis of patients with locally advanced thoracic esophageal squamous cell carcinoma after concurrent chemoradiotherapy (CCRT).Methods:A total of 158 patients with locally advanced thoracic esophageal squamous cell carcinoma undergoing CCRT in Shandong Cancer Hospital, Anyang Cancer Hospital of Henan Province, Tengzhou Central People′s Hospital of Shandong Province and the First Affiliated Hospital of China Medical University from August 2015 to October 2018 were selected as the research subjects. These patients were divided into standard-dose group (50.0-50.4 Gy, n=59) and high-dose group (>50.4 Gy, n=99) according to the radiotherapy dose. The overall survival (OS) and progression-free survival (PFS) of the two groups after treatment were compared. Kaplan-Meier method was used to calculate survival rate and survival comparison was performed by log-rank test. Cox proportional hazard regression model was used to analyze the adverse prognostic factors. The receiver operating characteristic (ROC) curve was used to analyze the predictive value of lung V 30 for patient prognosis. Results:In 158 patients with locally advanced esophageal squamous cell carcinoma, 19 cases (12.03%) had complete remission after CCRT, 103 cases (65.19%) had partial remission, 27 cases (17.09%) had stable disease, 9 cases (5.70%) had progression disease, and the total effective rate was 77.22%. The median OS of 158 patients was 41 months (95% CI: 25-57 months), and the 1- and 3-year OS rates were 76% and 51%, respectively. The median PFS was 24 months (95% CI: 13-35 months), and the 1- and 3-year PFS rates were 60% and 39%, respectively. The 1- and 3-year OS rates in the standard-dose group were 74% and 56%, and those in the high-dose group were 77% and 49%, with no statistically significant difference ( χ2=0.300, P=0.584). The 1- and 3-year PFS rates in the standard-dose group were 62% and 37%, and those in the high-dose group were 59% and 40%, with no statistically significant difference ( χ2<0.001, P=0.990). Univariate analysis showed that the length of the lesion, N stage, clinical stage, short-term efficacy of CCRT, planning target volume (PTV) D max, gross tumor volume (GTV) D mean, V 5, V 10, V 20, V 30, D mean of the left, right and bilateral lung were all the prognostic factors for OS and PFS (all P<0.05). Multivariate analysis showed that the length of the lesion ( HR=2.226, 95% CI: 1.244-3.985, P=0.007), N stage ( HR=2.819, 95% CI: 1.137-6.991, P=0.025), clinical stage ( HR=1.897, 95% CI: 1.079-3.334, P=0.026), short-term efficacy of CCRT ( HR=1.805, 95% CI: 1.250-2.606, P=0.002), left lung V 10 ( HR=0.811, 95% CI: 0.668-0.986, P=0.035), left lung V 30 ( HR=0.617, 95% CI: 0.408-0.933, P=0.022), right lung V 20 ( HR=2.067, 95% CI: 1.010-4.231, P=0.047), bilateral lung V 10 ( HR=1.299, 95% CI: 1.016-1.662, P=0.037) and bilateral lung V 30 ( HR=2.368, 95% CI: 1.142-4.910, P=0.021) were independent prognostic factors affecting OS. N stage ( HR=2.433, 95% CI: 1.201-4.931, P=0.014), short-term efficacy of CCRT ( HR=2.067, 95% CI: 1.391-3.071, P<0.001) and bilateral lung V 30 ( HR=0.113, 95% CI: 0.018-0.719, P=0.021) were independent prognostic factors affecting PFS. The ROC curve for predicting OS and PFS showed that the optimal cut-off value of bilateral lung V 30 was 9.5%. Conclusion:Compared with the standard-dose group, increasing the dose of radiotherapy fails to improve the long-term survival of patients with locally advanced thoracic squamous cell carcinoma. Lesion length, N stage, clinical stage, short-term efficacy of CCRT, left lung V 10 and V 30, right lung V 20 , bilateral lung V 10 and V 30 are independent prognostic factors for OS in patients with locally advanced thoracic squamous cell carcinoma. N stage, short-term efficacy of CCRT and bilateral lung V 30 are independent prognostic factors for PFS. When bilateral lung V 30≤9.5%, the patients′ OS and PFS will benefit from the treatment.
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Objective:To observe the feasibility of magnetic resonance (MR)-guided stereotactic body radiotherapy (SBRT) for non-small cell lung cancer, and analyze the dosimetric differences in the presence or absence of magnetic field.Methods:Three patients with non-small cell lung cancer were prospectively treated with MR-guided linac (MR linac) for SBRT, and the dose was calculated with or without magnetic field models. The differences of dose distribution with or without magnetic field models were compared. At the same time, the target coverage, plan pass rate and treatment time were described, and the complexity of the conventional accelerator backup plan and the magnetic field model were compared.Results:The treatment time of 3 patients was (36.67±6.11) min, and the average time of online adaptive planning was (14.4±1.7) min, which was basically tolerated by patients. The treatment plan pass rate (3%/3 mm) was 98.9%, the Gamma pass rate (3%/3 mm) of the online plan during treatment was 98.5% and the target coverage was 99.1%, which met the clinical needs. The dose in the low dose area of the lung was slightly lower than that in the case without magnetic field, whereas the dose in ribs and skin was slightly higher than that in the plan without magnetic field. The number of machine unit (MU) for online adaptive plan was slightly higher than that of the reference plan, and the number of MU for the conventional accelerator standby treatment plan was significantly lower than that of the MR linac plan under the same target coverage. The follow-up results showed that there was no adverse reaction, and the short-term efficacy was partially relieved.Conclusions:In the case of considering the influence of magnetic field, the treatment plan meeting the clinical needs can be obtained. It is proven that SBRT radiotherapy for lung cancer guided by magnetic resonance accelerator is feasible, whereas the treatment time and process are complex.
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Objective:To discuss the feasibility of using online and offline combined multidisciplinary team (MDT) diagnosis-treatment mode in cancers diagnosis and treatment by comparing the comprehensive diagnosis and treatment plans formulated by online and offline MDT diagnosis-treatment mode.Methods:A total of 168 esophageal cancer patients collected from March 17, 2020 to May 17, 2020 were took as the research objects in Shandong Cancer Hospital and Institute, through whom the consistency of the comprehensive diagnosis and treatment plans formulated by online and offline MDT diagnosis-treatment mode was evaluated. The clinical characteristics of patients with changed comprehensive diagnosis and treatment plans, such as age, Karnofsky performance status (KPS) score, whether combined with basic diseases, whether received anti-tumor treatment before and tumor location were analyzed, so as to explore the mechanism to improve the efficiency on the basis of quality assurance.Results:The results showed that 86.3% (145/168) of the comprehensive diagnosis and treatment plans obtained by offline MDT diagnosis-treatment mode were consistent with online diagnosis-treatment MDT mode. Cases with inconsistent comprehensive diagnosis and treatment plans were characterized by elderly (> 69 years) ( χ2=4.250, P=0.039), KPS score≥80 ( χ2=15.520, P<0.001) and combined with underlying disease ( χ2=7.135, P=0.008). Through further analysis, the changed cases were also characterized as with inadequate auxiliary examination or complex in imaging. Conclusion:The online and offline combined MDT diagnosis-treatment mode is feasible. For the patients characterized of elderly (> 69 years old), KPS score ≥80, combined with underlying diseases, with incomplete auxiliary examination or complex in imaging, the offline MDT diagnosis-treatment mode should be adopted or supplemented.
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Objective:To investigate the efficacy and adverse effects of pegylated recombinant human granulocyte colony-stimulating factor (PEG-rhG-CSF) in preventing neutropenia in patients undergoing sequential adjuvant radiotherapy after postoperative chemotherapy for breast cancer.Methods:A total of 43 female patients with breast cancer from January 2017 to January 2019 in Shandong Cancer Hospital and Institute were analyzed prospectively. Twenty-one patients in the experimental group were given 6 mg of PEG-rhG-CSF subcutaneously 1-3 days before radiotherapy. In the control group, 22 patients were enrolled without PEG-rhG-CSF utilization. The lowest absolute neutrophil count (ANC), the number of days of radiotherapy interruption due to neutropenia, the number of recombinant human granulocyte colony-stimulating factor (rhG-CSF) used during radiotherapy and the occurrence of drug-induced skeletal muscle pain in the two groups were statistically analyzed.Results:No neutropenia fever was observed in the two groups during radiotherapy. In the experimental group, there was no case of grade Ⅲ neutropenia; while in the control group, there were 3 cases of grade Ⅲ neutropenia. The median value of the lowest ANC in the experimental group was 1.56×10 9/L, higher than that in the control group (1.37×10 9/L), with a statistically significant difference ( Z=-2.261, P=0.023). The median number of rhG-CSF used in the experimental group was 1, which was smaller than 2 in the control group, and the difference was statistically significant ( Z=-2.498, P=0.012). The median numbers of days of radiotherapy interruption due to neutropenia were 0 and 3 in the experimental group and the control group, with a statistically significant difference ( Z=-3.117, P=0.001). One case (4.8%) of drug-induced skeletal muscle pain was found in the experimental group and 5 cases (22.7%) in the control group, with no statistically significant difference ( χ2=1.586, P=0.208). Conclusion:PEG-rhG-CSF can effectively prevent neutropenia caused by radiotherapy after postoperative chemotherapy for patients with breast cancer, and can reduce the interruption of radiotherapy and the use of rhG-CSF during radiotherapy, which is helpful to the smooth process of radiotherapy.
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Since the establishment of the Chinese Society of Therapeutic Radiation Oncology 33 years ago, radiation oncology has developed rapidly in China. Based on previous survey data, this paper summarizes and reviews the development of radiation oncology in China (excluding Hong Kong, Macao and Taiwan regions) from the perspectives of radiotherapy units, relevant professionals, equipment, technologies and subject development, and looks forward to the future direction, and proposes a new concept—" precision radiotherapy" .
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Radiotherapy is one of the main treatments for tumor with increasingly high request for technique precision and the equipment stability. Machine learning may bring radiotherapy simplicity, individualization and precision, and may improve the automatic level of planning and quality assurance. Based on the process of radiotherapy, this paper reviews the applications and researches on machine learning, with an emphasis on deep learning, and proposes the prospects in the following aspects: segmentation of normal tissue and tumor, planning, treatment delivery, quality assurance and prognosis prediction.
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Humans , Deep Learning , Machine Learning , Neoplasms , RadiotherapyABSTRACT
Objective To observe the long-term effect,adverse reaction and cosmetic outcome of early-stage breast cancer with hypofractionated whole-breast irradiation (HF-WBI) after breast-conserving surgery.Methods A total of 206 patients with stage 0-Ⅱ breast cancer after breast-conserving surgery were included in Shandong Cancer Hospital Affiliated to Shandong University from May 2014 to August 2017.According to radiotherapy fraction,patients were divided into HF-WBI group and conventional whole-breast irradiation (CF-WBI) group.In HF-WBI group,116 patients received whole-breast radiation to 42.56 Gy in 16 fractions followed by tumor bed boost of 9 Gy in 3 fractions or 10 Gy in 5 fractions.In CF-WBI group,90 patients received whole breast radiation to 50 Gy in 25 fractions followed by tumor bed boost of 10 Gy in 5 fractions.The 2-year local recurrence rate,2-year mortality rate,acute adverse reaction,late adverse reaction and cosmetic outcome of the two groups were analyzed.Results The 2-year local recurrence rates of HF-WBI group and CF-WBI group were 0.86％ (1/116) and 2.22％ (2/90) respectively,and there was no significant difference between the two groups (x2 =0.049,P =0.824).The 2-year mortality rates of the two groups were 0.86％ (1/116) and 0 (0/90) respectively,and there was no significant difference (P ＞ 0.999).There were 108 cases (93.1％) in HF-WBI group and 84 cases (93.3％) in CF-WBI group with grade 0-1 acute dermatitis,and 8 cases (6.9％) and 6 cases (6.7％) with grade 2-3 respectively,with no statistically significant difference (x2 =0.004,P =0.948).There were 97 cases (83.6％) in HF-WBI group and 79 cases (87.8％) in CF-WBI group with grade 0-1 bone marrow suppression,and 19 cases (16.4％)and 11 cases (12.2％) with grade 2-4 respectively,with no statistically significant difference (x2 =0.704,P =0.401).In the two groups,there were 1 case (0.9％) and 3 cases (3.3％) with grade 1-2 radiation pneumonitis,and 115 cases (99.1％) and 87 cases (96.7％) with no radiation pneumonitis respectively,and the difference was not statistically significant (x2 =1.626,P =0.202).There was 1 case (0.9％,1.1％) with grade 1 breast edema in each group,and 115 cases (99.1％) and 89 cases (98.9％) did not occur breast edema,with no statistically significant difference (x2 =0.033,P =0.857).In the late adverse reactions,there were 5 cases (4.3％) and 3 cases (3.3％) with skin pigmentation in HF-WBI group and CF-WBI group respectively.There were 2 cases (1.7％,2.2％) with grade 1 subcutaneous tissue fibrosis in each group,and there were 1 case (0.8％) and 2 cases (2.2％) with grade 1 pulmonary fibrosis respectively.The differences between the two groups were not statistically significant (x2 =0.000,P ＞ 0.999;x2 =0.000,P ＞ 0.999;x2 =0.049,P =0.824).The 6-month,1-year and 2-year cosmetic outcome good rates in HF-WBI and CF-WBI group were 96.5％ (111/115) and 93.3％ (84/90),92.1％ (105/114) and 90.0％ (81/90),91.4％ (53/58) and 87.2％ (41/47) respectively.The differences between the two groups were not statistically significant (x2 =0.526,P =0.468;x2 =0.277,P =0.599;x2 =0.476,P =0.490).The whole course of radiotherapy time in HF-WBI group was 25 days or 29 days,which was significantly shorter than the 40 days of CF-WBI group.Conclusion HF-WBI after breast-conserving surgery has the similar long-term effect,acute and late adverse reaction and cosmetic outcome compared with CF-WBI,and the treatment time is significantly shorter.It can be further promoted as the optimal adjuvant radiotherapy for early-stage breast cancer after breast-conserving surgery.
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Objective To investigate the relationship between texture features based on CT and radiochemotherapy sensitivity in patients with esophageal squamous cell carcinoma (ESCC).Methods A total of 92 ESCC patients treated at Shandong Cancer Hospital Affiliated to Shandong University between January 2014 and December 2017 were retrospectively collected.All patients were divided into responders (complete response + partial response) and nonresponders (stable disease + progression disease) according to therapeutic sensitivity.The texture features were extracted from CT images for positioning.And the patients were divided into training set (46 patients) and test set (46 patients) using train-test-split,training set for establishing predictive model and test set for model validation.Results There were 31 responders and 15 nonresponders in the training set,and the portion of responders was 67.4％.Univariate analyses showed that the histogram matrix (HISTO)-sknewess was significantly different between the two groups (Z =2.097,P =0.036) and the area under the curve (AUC) was 0.692 with 95％ CI of 0.539-0.820.Sknewess ≤-2.58 intended to be responders.Binary logistic regression of sknewess (Z =2.097,P =0.036) in HISTO,high gray level zone emphasis (HGZE) (Z =1.722,P =0.085) and small zone high gray level emphasis (SZHGE) (Z =1.640,P =0.101) in gray level zone-length matrix (GLZLM) showed that sknewess was the independent influence factor of sensitivity (OR =0.558,95 ％ CI:0.338-0.923,P =0.023),and the AUC of logistic regression model was 0.718 with 95％ CI of 0.550-0.886,which indicted that the model had the ability to predict treatment response of ESCC patients.The model was validated by using test set and the AUC was 0.706,and the sensitivity of the model was 70.6％ while the specificity was 69.0％.It showed that the model had certain ability in predicting treatment response.Conclusion CT texture analysis can predict the radio-chemotherapy sensitivity in patients with ESCC to some extent.
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Objective To analyze the efficacy of different clinical characteristics and treatment modalities for patients with primary esophageal small cell carcinoma (PESC),and to find out the prognostic factors,and provide reference for clinical treatment decision.Methods Patients with PESC who were treated at Shandong Cancer Hospital Affiliated to Shandong University from January 2008 to May 2017 were retrospectively enrolled.The clinical features were collected.Their disease progression time and survival status were determined by follow-up,and the follow-up ended in October 2017.Data analysis was performed using SPSS 25.0 software,and GraphPad Prism 7.0 was used for mapping.Survival analysis was performed by Kaplan-Meier method,and log-rank test was used to compare the differences in survival curves of each group.Factors with significant differences in univariate analysis were included in the Cox multivariate survival analysis.ROC curve was used to verify the sensitivity and specificity of the model.Results A total of 83 PESC patients with a complete follow-up were included in the study,including 68 males and 15 females.The average age was 61.93 years old (41-82 years old).The median progression-free survival (PFS) was 9.1 months (1.0-60.0 months) and the median overall survival (OS) was 26.1 months (1.8-60.0 months).Cox multivariate survival analysis showed radiotherapy or not (HR=0.321,95％ C I:0.184-0.559,P ＜0.001) and chemotherapy cycles (HR =0.841,95％CI:0.737-0.960,P =0.010) were independent prognostic factors for PFS.The Veterans Administration Lung Study Group (VALSG) staging (HR =3.050,95 ％ CI:1.606-5.794,P =0.001),radiotherapy or not (HR =0.312,95％CI:0.174-0.560,P ＜0.001),and chemotherapy cycle (HR =0.711,95％ CI:0.601-0.842,P ＜0.001) were independent predictors of OS.The ROC curve showed that the sensitivity and specificity of the PFS prediction model were 78.26％ and 73.33％,and the sensitivity and the specificity of the OS prediction model were 80.00％ and 58.49％.Conclusion VALSG staging is an independent predictor of PESC survival.Comprehensive therapy based on radiotherapy and chemotherapy can improve disease control,reduce metastasis,and improve survival.
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Hypofractionated radiotherapy after breast conserving surgery has become a new standard treatment of early breast cancer. Clinical researches show that α/ β value of breast cancer is lower than that of other tumors,and the breast cancer is more suitable for hypofractionated radiotherapy. Hypofractionated radio-therapy has good economic benefits,and long-term follow-up results from a number of classical randomized con-trolled studies have shown that hypofractionated whole breast irradiation is effective and safe. With the extensive application of hypofractionated irradiation,this technology has been gradually extended to regional nodal irradia-tion,postmastectomy radiotherapy and breast ductal carcinoma in situ.
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The linear quadratic (LQ) model and deduced biological equivalent dose (BED) model are widely applied in the radiobiological studies and the mathematic models of radiation oncology in clinical practice. However, the LQ model cannot accurately fit the experimental and clinical data in the high-dose region under the high-dose-per-fraction treatment mode. To resolve this issue, researchers have made modifications to the LQ models since 2008. In the paper, first, the theoretical basis and the application scope of LQ and BED models were introduced and the debate on whether LQ model is applicable to the high-dose-per-fraction radiotherapy was reviewed. Second, five modified models were introduced in two categories and their characteristics were summarized. Finally, current research situation and existing problems of radiotherapy using biological equivalent dose (BED) models were briefly summarized and the development trend of models was predicted.
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Objective To explore the pattern of lymph node metastasis and provide guidance for the delineation of clinical target volume for patients diagnosed with hypopharyngeal squamous cell carcinoma (HSCC).Methods A total of 123 patients who were initially diagnosed with HSCC by electrolaryngoscope and computed tomography (CT) of the head and neck in Shandong Tumor Hospital between 2014 and 2017 were recruited in this study.The lymph node metastasis was evaluated based on the diagnostic criteria of CT scan.The lymphatic metastasis ratio (LMR) at each node level was calculated.Analysis of variance (ANOVA) andx2 test were used to analyze the relationship between LMR and primary tumors.Results Among 123 patients,primary tumors were originated from the pyriform sinus (PS) in 101 cases (82.1％),posterior pharyngeal wall (PPW) in 15 (12.2％) and postcricoid (PC) in 7 (5.7％),respectively.The overall LMR was calculated as 84.6％ (n=104),in detail,84.2％ for patients with primary tumors originating from PS,93.3％ for those from PPW and 71.4％ for patients from PC,respectively.For PSderived tumors,the ipsilateral neck LMR at the level Ⅰa,Ⅰb,Ⅱa,Ⅱb,Ⅲ,Ⅳ,Ⅴ,Ⅵa,Ⅵb,and Ⅶ was 0,3.0％,66.3％,42.6％,46.5％,10.9％,5.0％,2.0％,7.9％,and 11.9％,respectively,and 0,0,14.9％,5.0％,3.0％,2.0％,0,0,3.0％,and 2.0％ for the contralateral neck.For PPW tumors,the ipsilateral neck LMR at the level Ⅰa,Ⅰb,Ⅱa,Ⅱb,Ⅲ,Ⅳ,Ⅴ,Ⅵa,Ⅵb,and Ⅶ was 6.7％,6.7％,66.7％,46.7％,46.7％,20.0％,0,13.3％,33.3％,and 60.0％,respectively,and 6.7％,6.7％,33.3％,26.7％,20.0％,20.0％,0,0,13.3％,and 33.3％ for the contralateral neck.For PC tumors,the ipsilateral neck LMR at the level Ⅱa,Ⅱb,Ⅲ,Ⅳ,Ⅴ and Ⅵb was 71.4％,28.6％,14.3％,14.0％,14.0％,and 14.3％,respectively,and the LMR at the level Ⅱa was 14.3％ for the contralateral neck.No lymph node metastasis occurred in other lymph node levels.The mean levels of lymph node metastasis for the T1-T4 stage tumors were 2.4,1.9,2.2,3.3 with statistical significance (P =0.023),and 2.2,4.5 and 1.6 for patients with the tumors originated from PS,PPW and PC (P=0.000).The PPW invasion was significantly correlated with the level Ⅶ metastasis (P=0.000),and PC or esophageal invasion was intimately correlated with the level Ⅵ metastasis (P=0.002 and 0.001).Conclusions The most common lymphatic metastasis includes ipsilateral neck Ⅱa,Ⅲ,and Ⅱb,whereas the level Ⅰ and Ⅴ are rarely observed.For PPW-derived tumors,the LMR at the level Ⅶ is up to 60.0％.The incidence of PC or esophageal invasion enhances the risk of level Ⅵ lymph node metastasis.
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Radiomics is an emerging tumor diagnosis and auxiliary detection technique that has undergone rapid development in the past few decades.The availability of new imaging equipment and reagents, as well as the use of standardized imaging protocol, has made quantitative and standardized imaging analysis possible.Radiomics is a field of study that involves the extraction of a large number of quantitative features from areas of interest in medical images using data-characterization algorithms, and transformation of these data into first-order or high-order data.The accuracy of clinical diagnosis and prognostic value of radiomics can be further improved by analyzing the relationship between data layers.Although radiomics has many advantages and has made great progress, its standardization, reliability, and application in large data and multicenter studies will need to be further optimized.
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Objective:To study the attachment and collagen deposition of human gingival firbroblasts (HGFs) on titanium surface with different topography.Methods:Titanium surfaces created by machining(group M),electrolytic etching(group ECE) and electrolytic etching and acid etching(group ECA) were observed by SEM.HGFs cultured on the titanium surfaces were observed by laser scanning confocal microscope.Attachment of the cells was examined by comparing the numbers of attached to detached cells,respectively.Collagen production and deposition were examined via a Sirius red-based stain assay and confocal laser scaning microscopy.Results:The surface rouphness (μm) of group M,ECE and ECA was 0.867 5 ± 0.136 8,1.749 8 ± 0.355 1 and 1.671 4 ± 0.297 0 (P＜ 0.05) respectively,Cell attachment was significantly weaker on machined surface than on ECE and ECA surfaces,while which was weaker on ECE surface than on ECA surface.Collagen production was the highest on the machined surface,followed by that on ECE and ECA surface,Collagen deposition displayed a parallel pattern on the machined surface,while it was multidirectional on the ECE and ECA surfaces.Conclusion:The ECA surface of titanium may be beneficial to HGFs attachment,the machined surface may promote collagen deposition.
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Objective:To compare the changes of marginal bone resportion between immediate implantation and delayed implantation after 12 to 24 months of definitive prostheses finished.Methods:41 patients were recruited and divided into immediate implant placement group(n =20) and delayed implant placement group(n =21).All implants were evaluated via radiograph after surgery,6 months after implantion,1 year and 2 years after prostheses placement respectively,the height of marginal bone was measured 6 month after implation,1 year and 2 years after prostheses placement.Results:After 6 month,1 year and 2 year the mesial marginal bone attachement (MBA) of immediate implant placement group increased by (1.35 ± 1.12),(2.16 ± 1.73) and (2.53 ± 1.65) mm,the distal by (1.46 ± 1.17),(1.94 ± 1.16) and (2.32 ± 1.68) mm,respectively (among the 3 time points of examination,P ＜ 0.05).As for the delayed implantation group,in the mesial area MBA increased by (-0.52 ± 0.47),(-0.69 ± 0.58) and (-0.97 ± 0.78) mm,in the distal area by (-0.46 ± 0.44),(-0.60 ± 0.45) and (-0.72 ± 0.63) mm (among 3 time points,P ＞ 0.05).Conclusion:Immediate implantation is superior to delayed implantation for marginal bone attachement of dental implant.
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Objective To investigate the consensus and controversies on the delineation of radiotherapy target volume for patients with locally advanced non-small cell lung cancer (LA-NSCLC).Methods Questionnaires including 15 questions on the delineation of radiotherapy target volume of NSCLC were sent to 12 radiation departments in China in November 2015.A patient with LA-NSCLC was selected by Fudan University Shanghai Cancer Center, and simulation CT images and medical history data were sent to the 12 radiation departments.Twelve radiation oncologists from the 12 radiation departments showed and explained the delineation of radiotherapy target volume of their own, and the patient was discussed by all experts in the sixth multidisciplinary summit forum of precise radiotherapy and chemotherapy for tumor and lung cancer.Results All receivers of the questionnaire answered the questions.The standard lung window width/level for the delineation of lung cancer was 800-1600/-600 to-750 HU, and the mediastinum window was 350-400/20-40 HU.Respiratory movement was measured by stimulator, 4D-CT, and stimulator+4D-CT with 2-5 mm expansion based on experience.The primary clinical target volume (CTV) was defined as gross target volume (GTV) plus 5-6 mm for squamous carcinoma/5-8 mm for adenocarcinoma.The metastatic lesion of mediastinal lymph nodes was delineated as 5 mm plus primary lesion in 6 departments and as primary lesion in another 6 departments.Of the 12 departments, 10 applied 5 mm of set-up error, 1 applied 3 mm, and 1 applied 4-6 mm.For V20 of the lungs, 10 departments defined it as<30%, 1 as<35%, and 1 as 28%.Nine departments defined the radiation dose of concurrent chemoradiotherapy (CCRT) for LA-NSCLC as 60 Gy in 30 fractions, 62.7 Gy in 33 fractions in 1 department, 50-60 Gy in 25-30 fractions in 1 department, and 60-70 Gy in 25-30 fractions in 1 department.For the delineation of target volume for the LA-NSCLC patient treated with CCRT, the primary planning target volume (PTV) was defined as GTV plus organ movement (IGTV) and set-up error (GTV→IGTV→PTV) in 3 departments, as CTV plus organ movement (ITV) and set-up error (GTV→CTV→ITV→PTV) in 8 departments, and as CTV plus set-up error/IGTV plus 5-6 mm for squamous carcinoma/5-8 mm for adenocarcinoma (CTV) and set-up error (GTV→CTV→PTV/GTV→IGTV→CTV→PTV) in 1 department.For the delineation of PTV in the mediastinal lymph node, GTV→IGTV→PTV was performed in 3 departments, GTV→CTV→ITV→PTV in 8 departments, and GTV→CTV→PTV in 1 department.For 10%-100% patients with LA-NSCLC, the radiation field needed to be replanned when 38-50 Gy was completed.There was no unified standard for the optimal standardized uptake value (SUV) of positron emission tomography (PET)-computed tomography (CT) simulation and delineation.Seven departments had applied magnetic resonance imaging (MRI) simulation and 10 departments had applied stereotactic body radiation therapy (SBRT) for the treatment of early-stage NSCLC.For the delineation of PTV for early-stage NSCLC (T1-2N0M0), GTV→IGTV→PTV was performed in 5 departments, IGTV→PTV in 3 departments, and GTV→CTV→ITV→PTV in 2 departments.In all the 12 departments, peripheral early-stage NSCLC was given 6.0-12.5 Gy/fraction, 3-12 fractions and central early-stage NSCLC was given 4.6-10.0 Gy/fraction, 5-10 fractions.The results of discussion on the delineation of target volume for the patient were as follows:respiratory movements should be measured by 4D-CT or simulator;the lung window width/level is 1600/-600 HU and the mediastinal window width/level is 400/20 HU;the primary controversy is whether the involved-field irradiation or elective nodal irradiation should be used for the delineation of CTVnd in the mediastinal lymph node.Conclusions Basic consensus is reached for the delineation of target volume in LANSCLC in these aspects:lung window width/level, respiratory movements and set-up error, primary lesion delineation, the radiation dose in CCRT, and the optimal time for replanning the radiation field.There are controversies on the optimal SUV in the delineation of target volume based on PET-CT simulation, the optimal dose fractionation in SBRT for early-stage NSCLC, and the delineation of CTVnd.
ABSTRACT
Cone-beam computed tomography (CBCT)-guided radiotherapy has been widely used in radiotherapy, but it still has many limitations.Using magnetic resonance imaging (MRI) instead of CBCT for imaging-guided radiotherapy can not only make use of the advantages of MRI, but it also allows for online and real-time tracking of tumor motion and biological changes.This technique truly realizes the real-time MRI-guided adaptive radiotherapy (ART) in anatomy and biology, and sets another milestone in the advancement of radiotherapy.This review summarizes the technical advantages of MRI-guided radiotherapy, the basic structure and type of MR-Linac, and the technical difficulties and solutions of MRIgART.