Objective To investigate the relationship between dose-volume histogram (DVH) parameters and the late side effects (LSE) of the rectum in external-beam radiotherapy combined with computed tomography (CT)-based brachytherapy for locally advanced cervical cancer.Methods From 2008 to 2011,18 patients with stage ⅡB-ⅢB cervical cancer received external-beam radiotherapy and CTbased brachytherapy.The DVH parameters of high-risk clinical target volume (HR CTV) D90,point A dose,and D1 cm3 and D2 cm3 of the rectum and bladder were calculated by Oncentra HDR treatment planning system.Survival outcomes were followed up and rectal LSE were evaluated by RTOG/EORTC grades.Results The point A dose and HR CTV D90 were (93.0 ± 5.5) Gy and (73.6 ± 11.9) Gy,respectively.The median follow-up was 26 months.No recurrence was found during follow-up.Eight patients had mild and moderate rectal LSE,and their rectum D2 cm3 and D1 cm3 were significantly higher than those of patients without mild and moderate rectal LSE (D2 cm3:(87.4 ± 3.8) Gy vs.(75.8 ± 7.4) Gy,P =0.004 ; D1 cm3:(96.4±6.6) Gy vs.(80.5± 7.1) Gy,P=0.001).Conclusions HR CTV D90 in CT-based brachytherapy for locally advanced cervical cancer might be lower than that in the MRI-based plan.Rectum D2 cm3 is recommended to be less than 75 Gy.

Objective To investigate the relationship between the channel design of tandem-andovoid (T&O) applicator and the doses to organs at risk (OARs) and target volume in three-dimensional brachytherapy for advanced cervical carcinoma.Methods The data on 15 patients with advanced cervical carcinoma treated with three-dimensional brachytherapy in our hospital from 2015 to 2016 were collected,and 30 randomly selected high-dose-rate titanium T&O plans were retrospectively studied.CT-guided,conformal brachytherapy plans were generated.To simulate T&O applicator,the tandem applicator was virtually compared with the T&O plans with the target volume and OARs remaining unchanged.The DVH parameters of the rectum,bladder,and sigmoid were compared using the paired t test.Results For T&O plans and tandem applicator plans,the mean D2cc of the rectum was 387.8±96.8 cGy and 340.8±88.1 cGy,respectively;the mean D2cc of the bladder was 443.2± 87.5 cGy and 719.4± 243.0 cGy,respectively;the mean D2cc of the sigmoid was 330.3±88.8 cGy and 383.1±105.6 cGy,respectively.In the T&O plans,the doses to the rectum,bladder,and sigmoid were within the limits (rectum:D2cc ≤ 500 cGy;bladder:D2cc ≤ 550 cGy;sigmoid:D2c ≤ 500 cGy),while D2cc of the bladder and sigmoid was higher or partially higher than the limits.T&O plans showed a significant reduction in bladder D2cc and sigmoid D2cc compared with the tandem applicator plans (all P＜0.05).Conclusions Compared with tandem applicator plans,plans using T&O applicator provide significant sparing of bladder and sigmoid tissues in three-dimensional brachytherapy for cervical carcinoma,but the toxicities require further investigation.

ObjectiveTo summarize the results of stereotactic radiation therapy (SRT) with or without whole-brain radiotherapy (WBRT) in the treatment of multiple brain metastasis.MethodsFrom May 1995 to April 2010,totally 98 newly diagnosed multiple (2 - 13 lesions) brain metastases patients were treated in our centre.Forty-four patients were treated with SRT alone and 54 with SRT + WBRT.Dose fractionation schemes were 15 -26 Gy in 1 fraction or 24.0 -52.5 Gy in 2 - 15 fractions with 3.5 - 12.0 Gy per fraction,depending on the tumor volume,location,and history of prior irradiation.Kaplan-Meier and Cox proportional hazards regression analyses were used for survival analysis.The median age of the whole group was 55 years.The survival time was calculated from the date of radiation treatment to the day of death by any cause.ResultsThe median follow-up time for the whole group was 12 months,and the follow-up rate was 100％.The median overall survival time was 13.5 months for the whole group,there was no difference between SRT alone group and SRT + WBRT group ( 13.0 months vs.13.5 months,χ2 =0.31,P =0.578 ).The Karnofsky Performance Score ( KPS) at the time of treatment ( χ2 =6.25,P =0.012 ),the interval between the diagnosis of the primary tumor and brain metastases ( χ2 =7.34,P =0.025 ) and the status of extracranial metastases ( χ2 =4.20,P =0.040) were independent prognosis factors for survival in multivariate analyses.ConclusionsStereotactic radiation therapy is an effective and alternative treatment choice for multiple brain metastases.

Objective To evaluate target-volume coverage and organ at risk (OAR) protection achieved with conventional radiotherapy (CRT), three dimensional eonformal radiotherapy (3DCRT) , and intensity-modulated radiotherapy(IMRT) through dosimetric comparison in patients with cervical cancer after hysterectomy. Methods The planning CT scans of 10 patients treated with pelvic radiation after hysterectomy for cervical cancer were used to generate CRT,3DCRT and IMRT plans for this study. Clinical target volume(CTV) was contoured on the individual axial CT slices of every patient. The CTV was then uniformly expanded by 1.0 cm to create the planning target volume (PTV). The small bowel, rectum, bladder, bone marrow, ovaries, and femoral heads were outlined for the organ at risk (OAR) evaluation. The CRT ,3DCRT and IMRT plans were generated using commercial planning software. CRT plan was prescribed to deliver 45 Gy to the reference point,while IMRT and 3DCRT plans were 45 Gy to 95% of the FFV. Isodose line and dose volume histograms(DVH) were used to evaluate the dose distribution in CTV and OAR. Results For 10 patients, the average volume of CTV receiving the prescribed dose of CRT was significantly lower than 3DCRT( Q = 8.27,P ＜ 0.01 ) and IMRT( Q = 8.37, P ＜ 0.01 ), respectively. Comparing with the CRT plan,the 3DCRT and IMRT plans notably reduced the volume of bowel at 30 and 45 Gy levels. The IMRT plan significantly spared rectum and bladder at 30 and 45 Gy levels comparing with the CRT ( P ＜ 0.01 ) and 3DCRT( P ＜ 0.05 ) plans,while the 3DCRT plan significantly spared rectum and bladder at 45 Gy level comparing with the CRT( P ＜0.01 ) plans. For 4 patients with ovarian transposition, the average doses of ovary over 3 Gy were 2 patients with the 3DCRT and IMRT plans, and 2 with all three plans. Conclusions IMRT and 3DCRT are superior to CRT in improving dose coverage of target volume and sparing of OAR ,while IMRT being the best. The superiority of IMRT and 3DCRT is obvious in sparing bone marrow at high dose levels. IMRT,3DCRT and CRT could not spare the transposed ovary effectively.

Objective To summarize the clinical and pathological features of glycogen storage disease (GSD) type Ⅱ. Methods The clinical and pathological data of the 20 GSD type Ⅱ patients were reviewed. Results One patient with infantile-onset mainly presented hypotonia, muscle weakness, feeding difficulties, pulmonary infection and cardiomyopathy insufficiency and increase of serum creatine kinase (778 IU/L) and echographic evidence of hypertrophic cardiomyopathy were detected. Electromyography studies indicated a definite myopathy. Nineteen cases were late-onset, presenting a slowly progressive proximal myopathy with truncal involvement or with symptoms dominated by respiratory insufficiency. Not all muscles were equally affected. Increase of serum creatine kinase (208-2600 IU/L) was detected in 14 patients and normal level in 1 patient. Electromyography studies indicated a definite myopathy in 9 patients,with abnormal irritability in 1 patient and susceptible in 4 patients and myotonic discharge in 1 patient and no abnormalities in 2 patients. Echographic evidence of thickening of the interventricular septum and pulmonary hypertension were detected in 2 patients respectively. The common light microscopic feature of all case was a vacuolar myopathy with high glycogen content and acid phosphatase activity in the vacuoles. Conclusions GSD type Ⅱ often presents slowly progressive myopathy which often affect the toro and respiratory muscles.In most patients the serum creatine kinase level is elevated slightly. Muscle biopsy is of use to make the definite diagnosis of this disease.

Objective To investigate the value of the cerebrospinal fluid ( CSF ) cytology in diagnosis of intracranial germinomas by reviewing the outcomes of CSF cytology of 8 patients with intracranial germinomas. Methods Eight patients with positive CSF cytology at our clinic from January 2006 to June 2009 were reviewed. Conventional cytology and immunocytochemistry of CSF were performed. The relevant literature on the subject was reviewed. Results The patients, including 7 male and 1 female, developed endocrinological or neurological symptoms at the age of 13 to 25, and the typical neurological presentation included vertigo, headache, mental and behavior disorders, double vision and weakness of legs. The CSF cell count ranged from 0 to 300 leukocytes per cubic and elevated in 7 cases, typically lymphocytic inflammation. CSF level of human chorionic gonadotropin was 3.2-1087.0 mIU/ml, higher than the individual serum level. On CSF cytology studies, typical tumor cells of germinima were found, which had positive particles in cytoplasm on periodic acid Schiff stain. All presents had lymphocyte inflammation ( small lymphocyte predominant ). On immunocytochemical studies of CSF, the tumor cells were positive on placental alkaline phosphatase and Ki-67 stains. Conclusions CSF cytology is clinically useful for diagnosis of primary intracranial germinoma. Further clinical and cytological studies will be necessary for a better understanding of the biology of these tumors.

Objective To explore the safety and clinical efficacy of Ginkgo biloba lactone injection combined with Alteplase intravenous thrombolysis in treatment of acute ischemic stroke.Methods Totally 87 patients were recruited and divided into control group and test group.The,patients in control group (39 cases) were given Alteplase 0.9 mg/kg for injection,intravenous bolus total dose 10％ was given within 1 min,then intravenous infusion of the remaining 90％ was given in 1 h,and given basic therapy after 24 h.The 48 cases in test group,which were immediately iv Ginkgo biloba lactone injection after intravenous thrombolysis,6 mL added into 250 mL saline,once daily for 14 d,and also were given basic therapy after 24 h.All NIHSS scores were recorded before treatment,14 d and 90 d after treatment,and the adverse events were recorded.The modified Rankin scale (mRS) score and BI index were performed at 14 and 90 d after admission.Patients in two groups were classified according to the TOAST classification,and the patients with large-arteryatherosclerosis and small-artery occlusion were analyzed.Results No intracranial hemorrhage occurred in the two groups.The NIHSS score and mRS score of test group were significantly lower than that of control group,and BI index was significantly increased 90 d after treatment.The NIHSS score and mRS score of test group were significantly lower than that of control group,and BI index was significantly increased90 d after treatment of patients with large-artery atherosclerosis.But there was no significant difference between test group and control group of patients with small-artery occlusion.Conclusion Ginkgo biloba lactone injection combined with rt-PA intravenous thrombolysis in the treatment of acute ischemic stroke has high safety,and can improve the prognosis of patients.

Objective To evaluate the effects of four types of variance reduction techniques ( ring counter grid, high electron cutoff energy, termination of electron tracking in some structures, and emission direction?biased sampling of source) on the efficiency and accuracy of Monte Carlo simulation for the single source channel of the Leksell Gamma Knife. Methods The single source channel of the Leksell Gamma Knife was modeled using Monte Carlo software MCNP . Four types of variance reduction techniques were used to simulate the dose distribution in the water?like phantom. The computation efficiency and simulation result were compared between the four techniques. Results All techniques substantially improved the computation efficiency and had little effect on the accuracy of the simulation ( relative error less than 2. 5%) . However, if the electron cutoff energy was above 50 keV, the simulation became quite inaccurate due to neglect of the scattering of high?energy electrons and their dosimetric contribution to the penumbra. When the scattering of high?energy electrons and their dosimetric contribution to the penumbra were ignored, the dose to the Profile platform was overestimated and the dose to the penumbra was underestimated. Conclusions Rational use of variance reduction techniques can substantially improve the efficiency of Monte Carlo simulation for the single source channel of the Leksell Gamma Knife. However, the impact of variance reduction techniques on the accuracy of the simulation should be carefully evaluated.

Objective To develop whole breast irradiation with volumetric-modulated arc therapy (VMAT)-based hybrid intensity-modulated radiotherapy (IMRT) after breast conserving surgery for breast cancer,and to evaluate its value in clinical application.Methods Ten patients with breast cancer undergoing breast conserving surgery were enrolled.Two radiotherapy plans were designed based on hybrid fixed-beam IMRT/IMRT technique and hybrid VMAT/IMRT technique,respectively.One group received whole breast irradiation with a prescribed dose of 50 Gy in 25 fractions.The other group received whole breast irradiation with a prescribed dose of 50 Gy in 25 fractions,as well as simultaneous integrated boost to the tumor bed with 60 Gy in 25 fractions.The dosimetric parameters and delivery efficiency were compared between the two plans using paired t test.Results For patients treated with whole breast irradiation alone,there were no significant differences in conformity index and homogeneity index of target volume between the two plans (P=0.866,0.056);however,compared with the hybrid fixed-beam IMRT/IMRT technique,the hybrid VMAT/IMRT technique significantly increased the doses to organs at risk (OARs) and the number of monitor units (MUs) in the intensity-modulated field (P=0.000-0.050,P=0.002).For patients treated with whole breast irradiation with a simultaneous integrated boost to the tumor bed;however,the hybrid VMAT/IMRT technique significantly reduced the doses to the lung and spinal cord,number of MUs in intensity-modulated field,and delivery time compared with the hybrid fixed-beam IMRT/IMRT technique (P=0.004,0.001,0.000,0.000).Conclusions For patients treated with whole breast irradiation with a simultaneous integrated boost to the tumor bed,the hybrid VMAT/IMRT technique is highly promising for clinical application due to better OAR sparing and higher delivery efficiency.

Objective To evaluate the plan quality of volumetric modulated arc therapy (VMAT) in single brain metastasis compared with the stereotactic arc therapy (S_ARC).Methods 31 patients were replanned using VMAT and S_ARC technique.Prescription dose is 40 Gy delivered in 4 fractions covering at least 95％ of the target volume while keeping minimum doses to the volume of normal brain tissue.The plans were assessed and compared using the conformity indexes (CI),gradient indexes (GI),the mean dose of normal brain tissue,the volumes of normal brain tissue receiving 4 Gy doses,the number of monitor unit and treatment times.A paired t test or non-parametric Wilcoxon signed rank test was performed to analyze the difference between these two plans.Results VMAT plans increased dose conformity,but not dose gradient,compared with S_ARC plans.The median dose conformity index values were 0.815,0.818,and 0.779 (P =0.000,0.000),and the median dose gradient score index values were 5.865,5.706,and 3.133(P =0.000,0.000,0.000),in single arc,double arc VMAT plans and S_ARC plans,respectively.The mean dose of normal brain tissue was higher in VMAT plans.And the volume of the normal brain tissue receiving doses of 4 Gy in VMAT plans was significantly larger than the volume in S_ARC plans.The VMAT plans got higher MU number (P =0.000,0.000).And the mean treatment times were (2.7 ± 0.1) min,(2.8 ± 0.1) min,and (7.6 ± 0.2) min in single arc,double arc VMAT plans and S_ ARC plans,respectively (P =0.000,0.000).Conclusions The dosimetry of VMAT plan can meet the requirements of clinical,and is recommended in the treatment of big volume single brain metastasis or single brain metastasis in cerebellum.