The procedure of quality assurance(QA) and quality control(QC) is introduced. Then,the necessity of performing the QA and QC combining the corresponding international technical report and clinical practice is discussed. On the above basis,a system of QA and QC suitable to our daily work is established,which provides the guarantee for high quality service to patients and achieve economic and social benefits simultaneously.

Objective To compare dosimetrie difference of treatment planning of three-dimensional conformal radiotherapy (3D-CRT) and simplified intensity-modulated radiotherapy (slMRT) for non-small cell lung cancer (NSCLC). Methods Ten NSCLC patients treaded by radiotherapy were investigated. 3D-CRT and slMRT plannings were designed for each patient. The prescribed dose was 60 Gy(2 Gy/f), the 95 % of the planning target volume was received with this dose for each patient. The dose was computed with treatment planning system of ADAC Pinnacle3 using convolution/superpasition algorithm. Two plans were compared according to the homogeneity index (HI) and conformity index (CI) of dosimetry in the planning target volume and the parameters of dose-volume histogram (DVH) in normal tissue. Results In the terms of HI and CI, sIMRT had slight vantages over 3D-CRT. In the terms of DVH, compared with 3D-CRT, mean lung dose, V5, V10 and V20 of slMRT reduced by 14.81 %, 17.88 %, 19.15 % and 27.78 %, respectively. The dosimetric differences were not statistically significant between 3D-CRT and sIMRT in terms of esophagus, heart and spinal cord. Conclusions For NSCLC, sIMRT has some irreplaceable advantages over 3D-CRT and is worth spreading in clinical work.

The relationships in using efficiency and economic benefits of large-scale equipment and the cycle of turning back cost are discussed, and then the standards of full-load operation of large-scale equipment are discussed according to the analysis of utilization rate and a variety of radiotherapy techniques of large-scale equipment in past five years. On the above basis, some rational advices are proposed about how to reasonably use large-scale medical equipment and advanced treatment technique, providing high quality service for patients and achieving economic and social benefits simultaneously.

Objective To establish an efficiency calibration method without a radioactive source for Inspector 2000 gamma spectroscopy system.Methods At the fwst step,geometry parameters of the detector were properly specified by comparisons of FEPE(Full Energy Peak Efficiency)between Monte Carlo(MC)calculations and the average measured values of HPGe and NaI detectors using point sources(137 Cs).The differences between calculations and measurements were generally within ±10% for gamma rays.Then,Monte Carlo simulation was used to evaluate the counting efficiency of Nal(TI)and HPGe detectors for BOMAB phantoms.Corresponding efficiency curves and functions were fitted.Results The counting efficiency received from the fitted efficiency functions had a good agreement with those from MC simulation.The bias for Nal detector ranged from-19% to 18%,while the bias for HPGe detector ranged from-11% to 17%.The above errors were totally acceptable in the on-site deployment during nuclear and radiological emergency events.Conclusions Monte Carlo method is simple,time and laborsaving in determing the counting efficiency of gamma spectroscopy system.

Objective To observe the translations of chemokine CXCL12 and its receptor CXCR4 in endometrial carcinoma tissues,and to evaluate their significance in clinical pathologic features of endometrial carcinoma.Methods From Jan.2012 to Dec.2014,52 tissue specimens of patients with endometrial carcinoma were admitted to the hospital,aged 55.6 ± 19.2 years,and 26 cases of normal endometrium as control,aged 52.3±16.5 years old.Expressions of CXCL12 and CXCR4 in the tissue specimens were detected by immunohistochemistry,and to analyze the relationship between the expressions and clini-cal pathological features,and FIGO stage,cell differentiation,lymph node metastasis and pathological type in endometrial carcinoma.Results In endometrial carcinoma,the positivity rates of CXCR4 and CXCL12 were 76.92% and 69.23% re-spectively.The positive expression rates of which were 34.62% and 30.77% in normal endometrium tissues,statistically significant (χ2 =11.826,P <0.01).The expression of CXCR4 was positively correlated with the differentiation of endome-trial carcinoma cells (P <0.05).In endometrial carcinoma,with the exception of CXCR4 expression and cell differentiation was positively related (r=0.386,P <0.05),CXCL12 and CXCR4 expression and clinical stage,pathological type and lymph node metastasis no correlation was found (P >0.05).Conclusion The results showed that the expression of CXCL12 and CXCR4 in endometrial carcinoma tissues was significantly increased,which may play an important role in the development of endometrial cancer.

Objective:To compare bone marrow-sparing intensity-modulated radiotherapy(BMS-IMRT)with conventional (four-field box[3DCRT]and anteroposterior-posteroanterior[CRT])techniques in the treatment of cervical cancer.Methods:For a cohort of 10 patients,BMS-IMRT,3DCRT and CRT planning were designed.The prescribed dose was 45Gy/1.8Gy/25f,95%of the planning target volume received this dose.Doses were computed with a commercially available TPS.Plans were compared according to dose-volume histogram (DVH)analysis in terms of PTV homogeneity and conformity indices(HI and CI)as well as OARs dose and volume parameters.Results:BMS-IMRT had an advantages over 3DCRT and CRT in terms of CI,but inferior to the latter two for HI.BMS-IMRT was superior to 3DCRT in reducing the dose to PBM,small bowel,bladder and rectum.Compared with CRT,BMS-IMRT reduced the volume irradiated to the doses from 30Gy to 40Gy,but increased the volume irradiated to the low doses from 5Gy to 20Gy.In addition,BMS-IMRT reduced the volume of small bowel,bladder,rectum at nearly all dose levels.Conclusion:BMS-IMRT reduced irradiation of PBM compared with 3DCRT technique.Compared with CRT technique,BMS-IMRT reduced the volume of PBM irradiated to high doses.Therefore,for patients with cervical cancer after hysterectomy,BMS-IMRT might reduce acute hematologic toxicity(HT)compared with conventional techniques.

Objective To study the effect of the location and volume of tumors on the normal lung dose-volume parameters for lung cancer. Methods An sphere with a diameter of 2 cm made of tissue-equiv-alent material used for simulating tumor was inserted into the superior lobe, middle lobe, inferior lobe of the right lung, and superior lobe, inferior lobe of the left lung of the Rando phantom, respectively. 5-field sIM-RT plans were designed. The prescribed dose was 60 Gy/2 Gy/30 f, and 99% of the planning target volume received this dose. Dose-volume parameters of normal lung tissue including V_5, V_(10), V_(20), V_(30), V_50 and mean lung dose were analyzed and compared. Results For the dose-volume parameters, the diameter and the po-sition of the tumor have a significant effect (P < 0.05). With the diameter expanding from 2 cm to 3 cm,the parameters associated with tumor in various lobes increased by a range between 3.83%-125.38%,while the parameters linked with tumor in different lobes increased by a range between 10.46%-51.46% with the diameter expanding from 3 cm to 4 cm. Conclusions Location and diameter of sphere-like tumor have obvious effect on dose-volume parameters. Knowing about the degree of influence will help oncologists and physicists to evaluate treatment planning better and reduce radiation pneumonitis.

Objective To compare bone marrow-sparing intensity-modulated radiotherapy (BMS-IMRT) with conventional intensity-modulated radiotherapy (IMRT) without considering pelvic bone marrow (PBM) as a planning constraint in the treatment of cervical cancer after hysterectomy. Methods BMS-IM-RT and IMRT planning were separately designed in a cohort of 10 patients with cervical cancer after hysterec-tomy. The prescribed dose was 95% planning target volume receiving 45 Gy/25 f. A commercially available TPS with convolution/superposition (CS) algorithm was used for dose calculation. Plans were compared ac-cording to dose-volume histogram (DVH) analysis in terms of PTV homogeneity (HI), conformity index (CI) as well as dose and volume parameters of organ at risks (OARs). Results BMS-IMRT was better than IMRT in terms of CI, but inferior to the latter for HI. When compared with IMRT, V_5, V_(10), V_(20), V_(30) and V_(40) of PBM in BMS-IMRT were reduced by 1.81% ,8.61% ,31.81% ,29.50% and 28.29%, respec-tively. No statistically significant differences were found between BMS-IMRT and IMRT for dose distritutions of the small bowel, bladder or rectum. Conclusions For patients with cervical cancer after hysterectomy, BMS-IMRT can reduce the PBM volume irradiated by low dose, which may reduce acute hematologic toxici-ties.

ObjectiveDouble-outlet right ventricle,which often associated with total anomalous pulmonary venous connection and complete endocardial cushion defects,has been considered a risk factor for biventricular repair procedure.To reviewed cases treated by biventricular repair for endocardial cushion defects with double outlet right ventricle.MethodsFrom July to November of 2009,6 patients (3 males and 3 females) aged from 7 to 24 (16.17±5.98) years and with endocardial cushion defects and double outlet right ventricle underwent operation of biventricular repair The duration of follow-up ranged from 10 days to 2 years(median,16 months).Endocardial cushion defects were repaired with a 2-patch technique.The artificial vascular patch was implanted to connect the ventricular septal defects and the aorta for draining the blood stream from the left ventricle to the aorta.The other patch was used to repair the ostium primum atrial septal defects.Right ventricular outflow tract obstructions was released and reconstructed by transplanting a bovine pericardium patch.If the size of pulmonary valve annulus was far more below the normal,a transannular pericardial patch was used.Rastelli procedure with a valved conduit between the right ventricle and the pulmonary artery would be performed if the obstruction in the right ventricular outfolw tract was severe.ResultsOne death occurred 2 days after the operation,resulting in a mortality rate of 16.6%.The case,a boy of 7 years old,had a mirror-image dextrocardia,complete endocardial cushion defect ( C type),anomalous pulmonary venous drainage and single atrium.In this case,the operation lasted for 8 hours,acute renal failure happened next day to the operation,the effect of CRRT was unsatisfied,and eventually cardiac arrest occurred as a result of hyperkalemia.The remaining cases had survived.Follow-up examinations showed that the systolic pressure gradients across the pulmonary valves decreased,with a range of 14 to 40 mm Hg,(23.9 ± 11.03) mm Hg.Mild mitral and tricuspid regurgiration were identified in 4 cases and moderate mitral regurgitation was identified in one case.The cardiac function in all patients was classified as NYHA class Ⅰ/Ⅱ,Conclusion Endocardial cushion defects with double outlet right ventricle can be corrected by means of biventricular repair procedure.The procedure was associated with a low mortality,The interim life quality of patients may be improved.The longterm outcomes should be further studied.

Objective: To compare inverse three-dimensional conformal radiotherapy (Inv 3D-CRT) and intensity modulated ra-diotherapy (IMRT) for non-small cell lung cancer. Methods: For a cohort of 10 patients, Inv 3D-CRT and three groups of IMRT plannings were designed for per patient. The prescribed dose was 60 Gy/2 Gy/30f, 95% of the planning target volume received this dose. Dose was computed with a commercially available TPS using convolution/superposition (CS) algorithm. Plans were compared according to the PTV_(95)V_(20) ratio (PTV_(95)V_(20)) and D_(max)-D_(min). Results: Compared with Inv 3D-CRT, the PTV_(95)V_(20) ratio of three groups of IMRT increased by 1.08 (P = 0.014), 0.72 (P = 0.089) and 0.42 (P = 0.318), respectively. Conclusions: For NSCLC, IMRT can reduce the dose to the lungs compared with inverse 3D-CRT by improving the conformity of the plan and is worth spreading in clinical work.