Objective To design a mobile personnel radiation protection equipment for operation in environments with high radiation such as spent fuel reprocessing plants, to achieve simultaneous protection against γ radiation, neutron radiation, and radioactive aerosol, to reduce the internal and external exposure dose of radioactive workers, and to meet the requirement of operation for two hours. Methods The core parts of the mobile personnel radiation protection equipment included a shielding chamber and a respiratory maintenance system. An automated chassis was used for the movement and lifting of the shielding chamber. MCNP software was used to simulate and calculate the protective effects of shielding chamber made of different materials and material thicknesses. Experimental verification of the shielding chamber design was conducted. Mathematical models were established to describe the variations in the content of various gases in the chamber with personnel operation time. A respiratory maintenance system, a harmful gas absorption device, and an automated mobile chassis were designed. Results The shielding chamber made of polyethylene with a thickness of 80 mm achieved an 80% neutron shielding rate. The respiratory maintenance system could support workers for 2 hours of operation inside the equipment. The mobile chassis allowed operation of the equipment with one person. Conclusion This mobile personnel radiation protection equipment can solve the problem in simultaneous protection against γ radiation, neutron radiation, and radioactive aerosol. The equipment can provide radiation protection for radioactive workers, reduce exposure dose, and reduce personnel burden. This system provides technical means for the operation and maintenance of equipment in high-radiation sites such as spent fuel reprocessing plants.

Objective:To investigate the effect of subacute exposure of Di(2-ethylhexyl)phthalate(DEHP)on endometrial decidualization and early pregnancy miscarriage in mice.Methods:CD1 mice were orally administrated with 300(low-dose group),1000(medium-dose group),or 3000 mg·kg-1·d-1 DEHP(1/10 LD50,high-dose group)for 28 days,respectively.An early natural pregnancy model and an artificially induced decidualization model were established.The uterine tissues were collected on D7 of natural pregnancy and D8 of artificially induced decidualization,respectively.The effects of a subacute exposure to DEHP on the decidualization of mice were detected by HE staining,Masson staining,TUNEL assay,and Western blotting.A model of spontaneous abortion was constructed in mice after subacute exposure to 300 mg·kg-1·d-1 DEHP,and the effect of impaired decidualization on pregnancy was investigated by observing the pregnancy outcome on the 10th day of gestation.Results:Compared with the control group,the conception rate was significantly decreased in the high-dose DEHP subacute exposure group(P＜0.05).HE staining showed that,compared with the control group,the decidual stromal cells in the low-and medium-dose exposure groups were disorganized,the nuclei of the cells were irregular,the cytoplasmic staining was uneven,and the number of polymorphonuclear cells was significantly reduced.Masson staining showed that compared with the control group,the collagen fibers in the decidua region of the DEHP low-dose group and the medium-dose group were more distributed,more abundant and more disorderly.TUNEL assay showed increased apoptosis in the decidua area compared to the control group.Western blotting showed that the expression of BMP2,a marker molecule for endometrial decidualization,was significantly reduced(P＜0.05 or P＜0.01).The abortion rate and embryo resorption rate were increased,and the number of embryos,uterine wet weight,uterine area and placenta wet weight were decreased in DEHP low-dose group compared to the control group stimulated by mifepristone,an abortifacient drug(P＜0.05 or P＜0.01).Conclusion:Subacute exposure to DEHP leads to impaired endometrial decidualization during early pregnancy and exacerbates the risk of adverse pregnancy outcomes in mice.

Objective On the premise of meeting the image quality requirements of simulated location for pediatric radiotherapy,the simulated localizable CT parameters are optimized through phantom scanning to reduce the radiation dose.Methods CatPhan700 phantom was used to simulate the child's body,Philip 24-row large-aperture spiral simulated localizable CT was performed,and the CT images were obtained by scanning the phantom at different mAs and tube voltages.The mAs range was set at 60-400 mAs,the scanning was performed every 20 mAs interval,and the kV was set at 80,100,and 120 kV.Image evaluation was carried out using parameters such as image noise(N10 and mean SD),uniformity,low contrast resolution,high contrast resolution,and the stabilities of HU values of Air,Acrylic,50%bone,LDPE,20%bone,Teflon,Polystyrene,DelrinTM,Lung,PMP and Water.The CTDIVol and DLP automatically calculated by the simulated localizable CT system were read to evaluate the radiation dose.Results At 100 kV,as mAs increased,both CTDI and DLP showed upward trends,and the fitting results were linear correlated,with slopes of 0.034 5 and 0.932 4.Image noise was decreased nonlinearly with the increasing mAs.When mAs increased from 60 to 140 mAs,N10 decreased from 0.25%to 0.14%,and SD reduced from 3.74 HU to 2.54 HU.When mAs reached 180 mAs or higher,N10 fluctuated between 0.1%and 0.12%,the mean SD fluctuated between 2.0 and 2.5 HU,and the downward trends obviously slowed down.When mAs increased from 60 to 200 mAs,the low contrast resolution of the image dropped from 0.53 to 0.29.The image uniformity,high contrast resolution and HU values of different substances were less affected by mAs.The image quality of 100 kV and 200 mAs scanning was close to that of 120 kV scanning,but the image quality of 80 kV scanning failed to meet the clinical requirements.Conclusion In order to reduce the radiation dose as much as possible,the mAs should be set at 200 mAs when the tube voltage is set at 100 kV for a simulated cylinder with a diameter of 20 cm.In the actual simulation scanning for pediatric radiotherapy,the scanning parameters should be fine-tuned according to the phantom results and the actual physical characteristics of children to satisfy the optimization principle for radiation protection.

Both morbidity and mortality of gastric cancer are in the front rank among malignant tumors.At present,enhanced CT is served as an important imaging method for preoperative diagnosis and assessment of gastric cancer,but it is mostly based on morphological evaluation and unable to perform quantitative analysis.The functional imaging technology represented by energy spectral CT and CT perfusion imaging has a variety of quantitative parameters,which is expected to make up for the shortcomings of conventional CT.The review introduces the basic principles of energy spectral CT and CT perfusion imaging,and summarizes their applications in the diagnosis,pathological classification,grading,staging and efficacy prediction of gastric cancer,aiming to improve the understanding of functional CT imaging for the pretreatment assessment in gastric cancer.

Gastrointestinal stromal tumors(GISTs)are the most common mesenchymal tumors of the gastrointestinal tract,and they are also genetically heterogeneous tumors.c-KIT gene or PDGFRA gene mutation is the main driving factor leading to its occurrence,and it is also one of the key factors affecting the treatment and prognosis of patients with GISTs.Imaging examination is non-invasive and can display tumors from multiple angles and directions,making it the main method for preoperative evaluation of GISTs.With the continuous development of imaging technology,non-invasive and definite genotyping of GISTs by imaging methods before surgery plays a positive role in the selection of targeted drugs and doses for patients and the evaluation of targeted treatment efficacy.This article reviews the imaging progress on the genotype of GISTs and the efficacy of targeted therapy.

Objective:To prospectively observe the changes of tumor-related symptoms in patients with nasopharyngeal carcinoma following the administration of nimotuzumab one week before radiotherapy.Methods:Non-metastatic nasopharyngeal carcinoma patients with positive epidermal growth factor receptor (EGFR) expression and symptoms caused by the primary lesion or metastatic cervical lymph nodes admitted to Cancer Hospital of Chinese Academy of Medical Sciences were prospectively recruited. Investigators recorded tumor-related symptoms in recruited patients one day before the first administration of nimotuzumab (D0) and conducted follow-up visits from day 2 to day 7 after the first administration (D2-D7) to document symptom changes. All recruited patients were asked to assess tumor-related symptoms on D0 and D7 by visual analogue scale (VAS) scores. VAS scores were analyzed by paired t-test. Results:From June 2020 to April 2023, a total of 21 patients met the inclusion criteria. The median age was 49 years (range: 27-69 years), with a male-to-female ratio of 1.3:1. Among the patients, 17 patients (81%) received concurrent nimotuzumab for 8 cycles, 7 cycles for 3 cases (14%), and 6 cycles for 1 case (5%), respectively. All patients completed symptom assessments as required. The overall response rate of symptoms after the first administration of nimotuzumab was 62%, with response rates of 4/6、5/8、4/10、4/10、4/11、3/11 for tinnitus, headache, aural fullness, secondary pain caused by neck mass, nasal bleeding, and nasal obstruction, respectively. The VAS scores for overall symptoms were significantly decreased after the administration of nimotuzumab one week before radiotherapy ( P<0.001), with the most significant decrease in VAS scores for tinnitus, aural fullness, and headache. Conclusion:The administration of nimotuzumab one week before radiotherapy significantly alleviates tumor-related symptoms in patients with nasopharyngeal carcinoma, particularly in alleviating tinnitus, aural fullness, and headache.

Objective:To evaluate the efficacy and safety of nimotuzumab in the treatment of advanced head and neck tumors by using meta-analysis.Methods:Randomized controlled trials (RCT) of locally advanced head and neck squamous cell carcinoma (LA-HNSCC) treated with nimotuzumab were searched from databases (Cochrane Library, PubMed, Embase, Wanfang Data and CNKI) for meta-analysis. The efficacy evaluation indexes included overall survival, progression-free survival, disease-free survival, objective response rate, and complete response rate. Adverse reactions were analyzed for safety evaluation. The heterogeneity results were evaluated by Chi-square test, the degree of heterogeneity was evaluated by I2, and the literature was statistically analyzed by random effects model. Results:A total of 11 RCT were included, consisting of 1 202 patients (602 in the intervention group and 600 in the control group). Compared with the control group, the overall survival was significantly prolonged, death risk was decreased by 22% ( HR=0.78, 95% CI=0.63-0.95, P=0.014), the progression-free survival was prolonged and the risk of disease progression was declined by 35% ( HR=0.65, 95% CI=0.53-0.81, P<0.01), and the disease-free survival was prolonged and the risk of recurrence was decreased by 29% ( HR=0.71, 95% CI=0.55-0.91, P<0.01), the objective response rate ( RR=1.37, 95% CI=1.20-1.55, P<0.01) and complete response rate ( RR=1.30, 95% CI=1.15-1.46, P<0.01) were significantly improved in the intervention group. In addition, adding nimotuzumab did not increase the incidence of adverse reaction ( RR=0.98, 95% CI=0.93-1.03, P=0.41). Conclusion:Nimotuzumab can significantly prolong long-term survival and improve short-term efficacy with high safety in LA-HNSCC patients.

Objective:This study aimed to evaluate the clinical features and treatment outcomes of the value of response-adapted treatment following radiotherapy and induction chemotherapy follwing subsequent comprehensive therapy in patients with resectable locally advanced hypopharyngeal carcinoma. Methods:This cohort study was conducted from September 2010 to September 2020 in our hospital, 231 patients pathologically confirmed stage Ⅲ and ⅣB resectable locally advanced hypopharyngeal carcinoma included. For the IC-directed ART strategy, IC is used to select good candidates to receive radical RT or CCRT, and others undergo surgery. He response-adapted strategy was determined based on the primary tumor response, which was evaluated at a dose of 50 Gy. If the response reached complete response or partial response（more than 80% tumor regression）, patients received radical RT or CCRT; otherwise, they received surgery, if possible, at 4 to 6 weeks after RT. The end points of the study were OS（overall survival）, progression free survival（PFS）, locoregional recurrence-free survival（LRRFS） and LDFS. Results:In IC-directed group, 75.0%（57/76） patients reached PR after 2 cycles of induction chemotherapy. While in RT-directed group, 70.3%（109/155） patients reached large PR at dose of 50 Gy. The median interquartile range follow-up period of the whole cohort was 63.8 months. The 5-year OS, PFS, LRRFS and SFL of the whole cohort were 47.9%、39.6%、44.3% and 36.2%, respectively. In evaluations based on the different treatment strategies, the 5-year OS and SFL were 51.3% versus 37.0%（HR 0.67; 95%CI 0.43-1.05; P=0.07） and 27.8% versus 39.8%（HR 0.68; 95%CI 0.46-0.99; P=0.04） between IC-directed and RT-directed groups. In additional, surgery complications did not significantly differ between these two groups. Conclusion:In this cohort study, the response-adapted strategy based on an early RT response facilitated better treatment tailoring, and higher laryngeal preservation compared with IC-directed strategies. This approach could provide a feasible laryngeal preservation strategy in patients with resectable locally advanced hypopharyngeal carcinoma.
Male ; Humans ; Cohort Studies ; Chemoradiotherapy ; Carcinoma ; Hypopharyngeal Neoplasms/therapy* ; Induction Chemotherapy

Objective:To analysis the clinical features and prognosis in oropharyngeal carcinoma with secondary primary tumor. Methods:A retrospective analysis was performed on 468 pathologically confirmed oropharyngeal cancer as the primary tumor patients with p16 status, excluded distant metastasis, and admitted to the Chinese Academy of Medical Sciences from January 2010 to December 2020. The clinical features and prognosis of the secondary primary tumor were analyzed. Results:Among 468 patients with oropharyngeal cancer treated at initial diagnosed, 222 cases were P16-negative. With a median follow-up time of 64.3 months, 66 cases developed second primary cancer, with an incidence of 29.3%, among which 63.6%（42/66） were synchronous and 36.4%（24/66） were heterochronous, esophagus was the most commonly involved site. The 5-year OS of p16-negative oropharyngeal carcinoma with synchronous second primary cancer, without second primary cancer and with heterogeneous second primary cancer were 26.3% and 57.3% and 73.2%（P=0.001）; The second primary cancer accounted for 11.2%（12/107） of the deaths in the whole group, among them, the heterochronous second primary accounted for 75.0%（9/12）. There were 246 patients with p16 positive, with a median follow-up time of 52.4 months, 20 patients developed second primary cancer（8.1%）. Among them, 65.0%（13/20） were synchronous and 35.0%（7/20） were heterochronous. Esophagus was the most commonly involved site. The 4-year OS of p16-positive with synchronous, heterochronous and non-second primary cancer group were 51.9%, 80.7% and 83.3%. Secondary primary cancer accounted for 3.8%（2/52） of all deaths in p16 positvie group. Conclusion:The incidence of second primary cancer of p16 positive and negative oropharyngeal carcinoma were different. The esophagus was the most commonly involved site regardless of p16 status. Regardless of p16 status, the survival of patients with synchronous second primary cancer was worse than those without second primary cancer. For p16-negative oropharyngeal carcinoma, the prognosis was better in patients with heterogeneous second primary cancer, the second primary cancer is one of the main causes of death.
Humans ; Carcinoma/diagnosis* ; Oropharyngeal Neoplasms/diagnosis* ; Retrospective Studies ; Neoplasms, Second Primary/diagnosis*

Objective:To evaluate the incidence, clinical characteristics and prognosis of second primary malignancies (SPMs) among patients with hypopharyngeal carcinoma (HPC) in real-world analysis.Methods:A total of 594 HPC patients admitted to Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College from 2010 to 2018 were retrospectively analyzed.The incidence and clinical characteristics of HPC patients complicated with SPMs were analyzed. Clinical efficacy was compared among different groups.Results:With a median follow-up time of 66.9 months, SPMs were present in 36.4% (216/594) of HPC patients: 22.2% (132/594) were synchronous and 14.1% (84/594) were metachronous. The upper aerodigestive tract was the most common involved region. Compared with patients without SPMs, patients with synchronous and metachronous carcinoma in situ had similar 5-year overall survival (OS) of 42.2% vs. 44.5% ( P=0.958) and 62.2% vs. 44.5% ( P=0.240), respectively. Patients with synchronous invasive SPMs had a worse 5-year OS of 27.2% vs. 44.5% in their counterparts without SPMs ( P=0.001). Patients with metachronous invasive SPMs had similar 5-year OS of 50.2% vs. 44.5% in their counterparts without SPMs ( P=0.587). SPMs accounted for 42.5% of total death in metachronous invasive SPMs group. Conclusions:Patients with HPC have a high probability of developing SPMs. Moreover, the incidence of complicated with esophageal/gastric carcinoma in situ or metachronous SPMs exerts no effect on prognosis, while the occurrence of synchronous SPMs significantly affectes the prognosis of patients. However, the incidence of SPMs is still one of the main death causes in metachronous invasive SPMs group.