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Objective To evaluate the secondary cancer risk to various organs due to radiation treatment for early left-sided breast cancer using 6 MV X-ray flattening filter free (FFF) and flattening filter (FF) modes.Methods Two techniques,6 MV FFF and 6 MV FF X-rays modes,were used to develop the two tangential fields d-IMRT plans for 20 early left-sided breast cancer patients respectively.For all the patients,the dose to surrounding tissues was minimized as low as possible,the 95％ volume of the planning target volume (PTV) and clinical target volume (CTV) was consistent with the prescribed dose.The beam parameters and the plan optimization parameters of FFF modes were in consonance with FF modes.The radiation doses and volumes of the planning target volumes,organs at risk and normal tissue were detected by dose-volume histogram.And then,the excess absolute risk(EAR) of contralateral breast,ipsilateral lung,contralateral lung,thyroid and liver were calculated using the radiotherapy-induced secondary primary cancer risks models.Results The treatment plans of two groups met the requirements of clinical.The FFF d-IMRT techniques resulted in a systematic reduction of the organ equivalent dose (OED) (t =2.18-9.72,P ＜ 0.05),and the EAR (t =2.11-9.99,P ＜ 0.05) of contralateral breast,ipsilateral lung,contralateral lung,thyroid and liver was compared to the FF IMRT techniques,especially for the contralateral breast.Conclusions Both FFF and FF d-IMRT plans can achieve comparable target dose coverage in patients with early left-sided breast cancer,while the FFF d-IMRT techniques could reduce the excess absolute risk of contralateral breast,ipsilateral lung,contralateral lung,thyroid and liver.These results are of clinical importance,especially for the early-stage patients with an overall good prognosis.
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Objective To compare the survival effects between using electron beams (EB) and modulated X-ray beams (XB) for boosting irradiation in breast cancer patients after breast-conserving surgery and postoperative radiotherapy.Methods This study retrospectively included 485 breast cancer patients who underwent breast-conserving surgery at Beijing Cancer Hospital.All patients underwent either EB or XB for tumor bed boost irradiation (10-16 Gy/5-8 fractions) after whole-breast irradiation of 46-50 Gy/23-25 fractions.Results Median follow-up time for the cohort was 96.04 months.Statistically significant increase of local recurrence free Survival (LRFS) was observed in XB group than in EB group.The 5-year and 10-year LRFS was both 98.4％ in XB group,as well as 94.2％ and 93.2％ in EB group,respectively (x2 =4.190,P ＜ 0.05).But there was not statistically significant difference in 5-year and 10-year overall survival (OS) between XB group(96.7％ and 95.8％) and EB group(94.9％ and 89.4％),respectively (P ＞ 0.05).The multivariate analysis showed that LRFS was significantly correlated with age≤40,positive pathological lymph nodes and positive expression of Her-2 receptor.But boost irradiation method was not independent prognostic factor for LRFS and OS (P ＞ 0.05).Conclusions For cancer patients treated with breast-conserving surgery and whole-breast postoperative radiation followed by a boost irradiation to tumor bed,XB irradiation was superior to EB irradiation in term of LRFS,yet no difference of OS was observed in both groups.
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Objective:To investigate the association between p53 codon 72 polymorphism and the prognosis of breast cancer pa-tients receiving chemotherapy and radiotherapy after surgery. Methods:A total of 427 breast cancer patients treated with chemo-radio-therapy after surgery at Beijing Cancer Hospital were selected for this study. Polymerase chain reaction–restriction fragment length polymorphism was adopted to analyze the p53 codon 72 polymorphism. Survival analysis was conducted to compare the disparities of recurrence and survival among the patients with different p53 codon 72 polymorphic variants. Results:The distribution of three geno-types of p53 codon 72 in our cohort is as follows:Pro/Pro 18.3%(78/427), Pro/Arg 44.0%(188/427), and Arg/Arg 37.7%(161/427). No significant difference was observed among the local recurrence-free survival (LRFS), loco-regional recurrence-free survival (LR-RFS), distant disease-free survival (DDFS), and overall survival (OS) among the three genotypes (all P>0.05). Among the 303 estro-gen receptor (ER)-positive patients, OS was significantly better in patients with Arg/Arg genotype than those with Pro/Pro genotype (χ2=6.33, P=0.042). The multivariate analysis showed that the p53 codon 72 polymorphism is an independent factor of prognosis for LRFS, LRRFS, DDFS, and OS of ER-positive patients. For the ER positive patients with Pro/Pro genotype, the local recurrence, local-regional recurrence, distant metastasis, and mortality risks were 5.9 (HR=5.9, 95%CI 1.1-31.1, P=0.036), 3.1 (HR = 3.1, 95% CI 1.1-9.1, P=0.039), 2.8 (HR=2.8, 95% CI 1.3-6.0, P=0.010), and 4.0 (HR=4.0, 95% CI 1.3-12.0, P=0.013) times higher than those with Arg/Arg genotype, respectively. Conclusion:For ER-positive breast cancer patients who underwent surgery and chemo-radiotherapy, the local recurrence, loco-regional recurrence, distant metastasis, and mortality risk with Pro/Pro genotype are significantly higher compared to those with Arg/Arg genotype.
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Objective To compare the dosimetric differences of the targets and organs at risk (OARs) for early stage breast cancer patients receiving intensity modulated radiotherapy (IMRT) with supine or prone setups after breast conserving surgery.Methods After breast conserving surgery,15 left breast cancer patients with large and pendulous breasts were selected.Their planning CT images were acquired with supine and prone orientations respectively,based on which IMRT plans of 2 tangential fields were developed using the same optimization parameters.Treatment plans of the two setups were evaluated by comparing the target dose distribution,the doses and irradiated volumes of the heart,left lung,and right breast,and the monitor units (MUs).Results Superior conformal index (CI) was observed in the plans of prone setup than the supine cases (0.79 ± 0.05 vs.0.72 ± 0.04,W =138,P ＜ 0.01).The homogeneity index (HI) of prone positioning was also better than that of supine setup (1.09 ±0.01 vs.1.12 ± 0.02,t =-4.7,P ＜0.01).The planning target volume (PTV) receiving 95％ of prescribed dose (V95％),and the minimum doses (Dmin) of the prone cases were significantly higher than the supine patients (t =7.1,6.4,P＜0.01).Higher mean doses (D) were observed in prone cases (W=153,P＜0.01).The maximum doses (Dmax) of the supine plans were lower than the prone cases (t =-3.6,P ＜0.01).The right breast volumes receiving 5 Gy doses or higher (V5) were less in the supine cases than the prone plans (W=160,P ＜0.01).The heart volumes received no less than 30 Gy (V30),D of the heart,and the left lung volumes received higher than 20 Gy or 5 Gy (V20,V5) of the supine plans were significantly higher than the prone cases (W =133,120,120,P ＜0.01).No significant difference was observed on the MUs.Conclusions For cancer patients with large and pendulous breasts receiving IMRT after breast conserving surgery,prone setup leads to better homogeneity of target dose distribution,and reduces the doses and irradiated volumes of the heart and lungs.
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Objective To compare the dosimetric differences of target and organs at risk (OAR) induced by the tangential and non-coplanar multi-fields used in the dynamic intensity modulated radiotherapy (IMRT) plans for breast cancer patients after breast-conserving surgery.Methods Forty patients with early-stage left breast cancer after breast-conserving surgery were included.Based on the CT anatomy of the same patient,dynamic IMRT treatment plans using two tangential fields,3,4 and 5 non-coplanar fields were designed respectively utilizing the same optimization objects.The plans were compared by means of target dose distribution,the doses and irradiated volumes of heat,left lung,right breast,and total monitor units (MUs).Results The conformal index (CI) and homogeneity index (HI) of planning target volume (PTV) in the plans using 4 and 5 fields were better than that using 2 fields (P ＜ 0.05).Maximum doses (Dmax) in PTV were significantly lower in the plans of 4 and 5 fields than of 2 fields (P ＜0.05).Yet the plans of 4 and 5 fields generated significant higher minimum doses (Dmin) in PTV than that of 2 fields (P ＜ 0.05).No significant difference was observed between plans of 2 or 3 fields.Across the four plans,the differences of right breast V5 (relative volume acquired at least 5 Gy of dose),heart V30,heart mean dose (D),left lung V20,V5 and D were not significant.Yet the disparities of total MUs were statistically significant (F =25.63,P ＜ 0.05).The least MUs were used by the 2 fields and the most MUs were observed in the 5-field plans.Conclusions Comparing with IMRT plans of 2 fields,using 4 or 5 non-coplanar fields can improve the target dose distribution without increasing OAR doses.As a tradeoff,more MUs are needed for multi-fields plans.
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Objective To compare the dosimetric difference between volumetric are modulation with RapidArc and fixed field dynamic IMRT for breast cancer radiotherapy after breast-conserving surgery.Methods Twenty patients with early left-sided breast cancer received radiotherapy after breast-conserving surgery.After target definition,treatment planning was performed by RapidAre and two fixed fields dynamic IMRT respectively on the same CT scan.The target dose distribution,homogeneity of the breast,and the irradiation dose and volume for the lungs,heart,and eontralateral breast were read in the dosevolume histogram (DVH) and compared between RapidAre and IMRT.The treatment delivery time and monitor units were also compared.Results In comparison with the IMRT planning,the homogeneity of clinical target volume (CTV) ,the volume proportion of 95% prescribed dose (V95%) was significantly higher by 0.65% in RapidAre (t =5.16,P = 0.001) ,and the V105% and V110% were lower by 10.96% and 1.48 % respectively,however,without statistical significance (t =-2.05 ,P =0.055 and t =-1.33 ,P =0.197).The conformal index of planning target volume (PTV) by the Rap~dAre planning was (0.88±0.02),significantly higher than that by the IMRT planning [(0.74±0.03),t = 18.54,P < 0.001].The homogeneity index (HI) of PTV by the RapidArc planning was 1.11±0.01,significantly lower than that by the IMRT planning (1.12±0.02,t =-2.44,P =0.02).There were no significant differences in the maximum dose (Dmax) and V20 for the ipsilateral lung between the RapidArc and IMRT planning,but the values of V10,V5 ,Dmin and Dmean by RapidArc planning were all significantly higher than those by the IMRT planning (all P < 0.01).The values of max dose and V30 for the heart were similar by both techniques,but the values of V10 and V5 by the RapidArc planning were significantly higher (by 18% and 50% ,respectively).The V5 of the contralateral breast and lung by the RapidArc planning were increased by 9.33% and 3.04% respectively compared to the IMRT planning.The mean MU of the RapidArc was 608 MU,significantly higher than that by the IMRT planning (437 MU,t = 10.86,P < 0.001).The treatment time by the RapidArc planning was 111.3 s,significantly longer than that by IMRT planning (103.6 s,t = 3.57,P = 0.002).Conclusions The RapidArc planning improves the dose distribution of CTV and homogeneity of PTV for breast cancer radiotherapy after breast-conserving surgery.However,it significantly enlarges the volume of normal tissues irradiated in low dose areas,prolongs the treatment delivery time,and increases the MU value in comparison with IMRT.
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<p><b>OBJECTIVE</b>This study was to introduce the method for obtaining accurate 3D data of soft tissues using a 3D scanner under non-contact condition and the standard 3D measurement of the nasal orbit fossa for plastic surgery.</p><p><b>METHODS</b>A 3D laser scanner and the Geomagic software were used to obtain the standard facial contour of 30 Chinese people. The nasal orbit fossa, as the feature of beauty, was measured and the data were analyzed.</p><p><b>RESULTS</b>3D measurement exhibited the three-dimensional facial shape at every meaningful angle, with the advantages of high precision of 0.01 mm. We determined the lowest point and described the 3D feature of the nasal orbit fossa.</p><p><b>CONCLUSIONS</b>This method can illustrate the relation of the nasal orbit fossa and the surrounding structure. It is a new approach to facilitate preoperative plans, operation simulation and postoperative evaluation.</p>
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Adult , Female , Humans , Male , Image Processing, Computer-Assisted , Imaging, Three-Dimensional , Methods , Lasers , Nose , OrbitABSTRACT
This paper reports the identification of vaginal secretions from the following stains by SDS-PAGGE,i.e.vaginal secretion stains and mixed stains kept at—30℃,4℃ for 3 years and at roomtemperature for 9 years.The method was applied to the forensic practice.
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The protein band patterns of 102 Chinese male's seminal plasma demonstrated bySDS-PAGGE were analyzed.The common electrophoretic patterns consist of 40 ormore protein bands belonging to 3 divisions.Some band patterns are uniqus for theseminal plasma so that the seminal plasma can be distinguised from the human va-ginal fluid,saliva,colostrum and serum In addition,a variant band called 83kdtentatively was discovered in the seminal plasma.Its frequency is 8. 22?2. 81%.TheSDS-PAGGE pattern was successfully applied to the case work.
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Genetic polymorphism of the C1R subcomponent of human first complement component was in-vestigated in 360 unrelated Chinese individuals using isoelectric focusing followed by immunoblotting.Six common and four rare were detected. The allele frequencies were as follows: C1R * 1 = 0. 5181,C1R ? 2=0. 5291,C1R * 3= 0. 1472 and C1R * R(C1R * 5,C1R * 6,C1R * 12 and C1R * 13) = 0.0056. The distribution of allotypes fitted the Hardy-Weinberg equilibrium. This complemlement sys-tem is a useful genetic marker for anthropological studies and forensic science practice.