Objective To investigate the dosimetry and feasibility of target volume reduction in three-dimensional conformal radiotherapy for non-small cell lung cancer(NSCLC).Methods Two differ-ent radiation treatment planning,the conventional conformal planning and the small volume conformal plan-ning,were designed for 32 NSCLC patients.Dose-olume histograms were used to assess the dosimetric dis-parity in target regions and surrounding organs at risk.Results Small volume conformal planning could meet the demand of target dose.The least dose,the maximum dose,and the mean dose at subclinical targets were 50.93 Gy,54.60 Gy and(52.37 ±1.02)Gy,respectively.Comparing with the conventional conformal planning,small volume conformal planning reduced the mean dose of lung,spinal cord and esophagus(P<0.05).Conclusion Small volume conformal planning can meet the dosimetric requirement of target vol-ume for NSCLC and reduce the dose of normal tissues,which is worthy of further clinical study.

Myocardial fibrosis is a predominant pathological change of radiation-induced heart disease (RIHD) in late stage.It often occurs several or more than ten years after radiotherapy and can lead to myocardial remodeling, impaired cardiac function, and heart failure.At present there is no effective method to prevent or reverse the development of radiation-induced myocardial fibrosis.Many cells, cytokines, and other factors are involved in the development and progression of myocardial fibrosis in RIHD and some of them have been validated.But most investigators focused on the pathological changes and related mechanisms in early stage, and myocardial fibrosis was just regarded as an endpoint event.The definitive mechanisms of myocardial fibrosis in late stage remain unclear.This paper reveiws the studies about general mechanisms of myocardial fibrosis in RIHD and summarizes the roles of microcirculation dysfunction, mast cells, several cytokines, hypoxia, oxidative stress, and renin-angiotensin system, and points out the future research direction of the pathogenesis of myocardial fibrosis in RIHD.It provides new ideas for discovering the potential targets for clinical intervention of myocardial fibrosis in RIHD.

Objection To investigate the spectrum and survival status of HIV positive cancer in HuBei province, China. Methods HIV positive cancer patients were added up and followed up who had registered in Zhongnan Hospital between January 2004 and June 2009. The prognostic features were determined for HIV patients with cancer. Results The average age of HIV positive and HIV negative group who suffered with malignant neoplasm were 42.5±8.8 years and 55.1±13.7 years respectively (P ＜0.05), mean CD4 counts were (220.9±142.3)/μl and (554.4±174.3)/μl, respectively (P ＜0.05), the types of common cancer were NHL, cervical cancer, liver cancer and lung cancer, colon cancer, breast cancer, respectively. Anticancer and/or ART treatment were the important positive prognostic factors. Additional factors such as age and CD4 count were associated with survival of cancer patients with HIV infection. Conclusion Mean age of HIV positive cancer patients is about 42 years old. NHL, cervical cancer and liver cancer are HIV associated malignant tumor. ART and anticancer can effectively prolong the survival of HIV infected patients with cancer.

Immunohistochemistry was used to detect the protein expression of Snail in 5 specimens jusxta-eancerous normal breast tissues, 35 specimens of cancerous tissues without metastasis and 20 specimens of breast carcinoma with lymphonode metastasis. Breast carcinoma cell line MDA-MB-231 was transfected with antisense Snail. Results showed that the expression of Snail protein was significantly higher in breast carcinomas than in their normal tissues. The mRNA and protein expressions of Snail in the breast carcinoma cells treated with antisense Snail was significantly decreased while the E-cadherin protein significantly increased (both P < 0.05). The number of invasive ceils treated with antisense Snail was (10.5±1.3)%, while in treated with EGFP was (68.2±2.1)% (P < 0.05). The abnormal expression of Snail contribute to the invasiveness of breast carcinoma. The antisense Snail could prevent the cells ability to invade in vitro, and the effect is related with the up-regulated E-cadherin protein.

Objective To divide computed tomography (CT) values into different ranges and investigate the influence of CT value division on dose calculation, and to propose a method to combine magnetic resonance imaging (MRI) with assigned CT values.Methods Ten CT images each were collected from patients with head and neck, chest, and pelvic tumors.Random sampling was performed for the CT values of main tissues or organs at the three parts, and then the mean CT value of each tissue or organ was calculated to divide the CT values into different ranges.A virtual phantom was built in the Varian Eclipse treatment planning system, and for the prescribed dose of 100 cGy, the machine output was recorded at different CT values.The influence of different CT value ranges on dose calculation was analyzed.The treatment plans of intensity-modulated radiotherapy were selected from 5 cervical cancer patients, and new CT values were assigned to the planning target volume (PTV) and organs at risk to obtain new CT images.The plans were transferred to the new CT images and compared with the results on the original CT images in terms of dosimetric parameters.Results After dividing the CT values into different ranges and verifying the results in dose calculation, the CT values corresponding to different human tissues or organs were-100 to 100 HU.The influence of CT value variation on dose calculation was within 3%.In the same treatment plan, there were small differences in dosimetric parameters between new CT images and original CT images.Dmax, Dmean, D98%, D95%, D5%, and D2% of PTV were all below 3%, and Dmax and Dmean of the bladder, rectum, small intestine, femoral head, and bone marrow were below 2%.Conclusions The influence of CT value division on dose calculation in the treatment planning for pelvic tumors is acceptable, so it can be used in combination with MRI.

Objective To evaluate the effect of home-made immobilization device with KV-CBCT in lung-SBRT and investigate its clinical use value.Methods Choosing 10 lung tumor patients (half centre type tumor;half peripheral type) random analysis the interfractional and intrafractional setup errors in the SBRT process by this fixed device with KV-CBCT.The concrete method is using Varian's KV-CBCT scans the patients before and after the SBRT each time,then make the registration between the reconstructed 3 d image and the planned CT image (both based on bone landmark),we then obtain the average setup errors in LR,AP and SI directions.Simultaneously,this research make contrastive analysis of setup errors among this fixed device and other fixed devices such as vacuum pad,phantom in body IMRT.All data make one-factor analysis of variance by SSPS 17.0.Results All the setup errors data was gaussian distribution,the centre type interfraction was at (0.01 ±0.32) cm (LR),(-0.08 ±0.38) cm (AP),(0.14 ±0.36) cm (SI) of the cross section,peripheral type interfraction was at (0.01 ± 0.32) cm (LR),(-0.08 ± 0.38) cm (AP),(0.14 ± 0.36) cm (SI) of the cross section (P =0.001).We found out that the average of lung tumor's setup error at all three directions have no significant difference-the largest was the AP directions (P =0.003),the second was the SI direction (P =0.003) and the smallest was the LR direction (P =0.001).The central type has no significant difference at three directions.Compare to the other fixed device,the average setup errors of our device are (0.09 ± 0.33) cm (LR),(-0.10 ± 0.44) cm (SI),(0.17 ±0.35) cm (AP) better than the report at present paper.As the interfraction setup error was small enough by using this fixed device while it has beyond the system algorithm,the registration software of system shows (0.0 ± 0.0 cm).Conclusions The range of lung tumor motion can be cut down obviously and enhance each placement accuracy,repeatability,on SBRT with home-made immobilization device.

The effects of melittin on the activities of Na+-K+-ATPase and glucose-6-phosphate dehydrogenase (G-6-PD) which are on the membrane of red blood cell (RBC) are chosen as the index of this study. The possible target sites of these effects through enzyme activity determination by spectrophotometry are investigated, and the hemolytic process and the activity change of these two types of enzymes on the RBC membrane are discussed. The results show that the main mode of melittin inhibition to the activity of enzymes on the RBC membrane is the coexistence of adhesion/insertion form and free-state form, and the effect of the former is more stronger than the latter. The K+ binding site of Na+-K+-ATPase is one of the target sites of melittin. The membrane-insertion process of melittin synchronizes with the action of melittin on this enzyme. Melittin slowly inhibits the catalysis of G-6-PD through the action on G-6-P and NADP, and the extent in which melittin forms tetramers isclosely related to the enzyme activity. EDTA inhibits the aggregation of melittin, and interferes with its action on G-6-P. The biochemical mechanisms of melittin effects on the substrate G-6-P and the coenzyme NADP are similar, and the inhibition of melittin is not related to the structure of G-6-PD.

ObjectiveTo investigate the CT number linearity of the cone-beam CT (CBCT) images at the different spatial locations in the scanning area.MethodsThe CatphanS04 phantom at the different locations are scanned repeatcdly using the CBCT on the Varian 23EX linear accelerator.The phantom is located the isocenter point,eccentric 3 cm,eccentric 6 cm,and different points on the z-axis successively on the accelerator.The scanned mode is the standard head mode.The reconstructive thickness is 2.5 cm.The different densities inserts of CTP404 module on the different locations are measured via Eclips treatment planning system (TPS) and computed by Matlab 7.0 and the CT linear fitting are then processed.In order to understand better the linear distribution along with the value of CT in the spatial distribution the results are compared with the fan-beam CT.ResultsPhantom studies show that:CBCT has good linearity performance not only under the standard header (body) of the scanning conditions,but also on such locations including the cross-sectional,the sagittal,the coronal plane and the eccentric position ( R2 ＞ 0.953 ).Bowtie filtration device does not change the CT finearity but changes the value of CT.ConclusionsThe linearity of X-ray CBCT on the Varian linear accelerator is favorable.CBCT will be used in the TPS dose calculation via further correction of the CT value.

Objective To retrospectively analyze the clinical and pathological data of 48 patients with adenoid cystic carcinoma of the head and neck and screen out related factors that affect the patient's prognosis. Methods The overall survival rate of patients is used as the main indicator for observing prognosis. We selected 11 clinical and pathological factors as observation indicators that may have an impact on the survival and prognosis of patients. The relation between observation factors and the overall survival rate of patients was analyzed by Cox multivariate regression. Results The median follow-up time was 33.5(1-98) months. The 1-, 2- and 5-years overall survival rates were 95%, 91% and 87%. Local recurrence occurred in 14(29.2%) patients. Distant metastasis occurred in 22(45.8%) patients. Cox regression analysis showed that recurrence, distant metastasis and primary site were correlated with the overall survival rate of patients with head and neck adenoid cystic carcinoma (P < 0.05). Conclusion Adenoid cystic carcinoma is a relatively rare tumor of the head and neck with a low degree of malignancy. However, recurrence, distant metastasis and primary site have relatively great impact on the prognosis of patients.

Objective To analyze the clinical efficacy and prognosis of stereotactic body radiation therapy (SBRT) for pulmonary oligometastases.Methods Medical records of 104 patients with SBRT for pulmonary oligometastases in our hospital between 2012 and 2018 were retrospectively reviewed.SBRT was performed by intensity modulated radiation therapy (IMRT) technique before December 2015,and by helical tomotherapy (HT) technique in others.The local control (LC),progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method.Cox-regression was used for univariate analyses and multivariate analyses.The radiotherapy-related adverse events were evaluated by NCICTCAE V4.0.Results The 1-,2-and 3-year LC rates were 86.6％,75.9％ and 72.3％,respectively.The 1-,2-and 3-year PFS rates were 40.9％,28.4％ and 22.1％,respectively.The 1-,2-and 3-year OS rates were 75.9％,53.2％ and 43.53％,respectively.The median OS time was 26.6 months.Multivariate analyses showed that the pathologic type of primary tumor,the volume of lung oligometastases and the carcino-embryonic antigen (CEA) level before SBRT were the independent prognostic factors of LC (x2 =28.66,P＜0.05).The way of tumor progression after SBRT was the independent prognostic factor of OS (x2=40.01,P＜0.05).Meanwhile,there were no significant differences in the LC and OS between HTSBRT and IMRT-SBRT.Radiation pneumonitis was the major adverse event of SBRT (n =25,24.04％).Less than 7％ patients experienced grade 2 and above radiation pneumonitis.Conclusions SBRT shows high local control rates and tolerable adverse events in the treatment of pulmonary oligometastases.There were no significant differences in the clinical efficacy and adverse events between HT-SBRT and IMRT-SBRT,which means they are all suitable for clinical application.