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Objective:To evaluate the effect of image-guided with cone-beam computed tomography (CBCT) based on volumetric modulated arc therapy (VMAT)-flattening filter free (FFF) on the setup errors of stereotactic body radiotherapy (SBRT) in patients with spinal metastatic tumors.Methods:The clinical data of 15 patients with spinal metastatic tumors who underwent SBRT in Jilin Cancer Hospital from August 2020 to January 2022 were retrospectively analyzed. The radiotherapy dose of bone metastasis was 32 Gy per 4 times and CBCT scanning was performed before and after radiotherapy. Every patient received radiotherapy 4 times; all 15 patients underwent SBRT 60 times in total and 120 CBCT volume images were finally obtained and analyzed. The systematic error (Σ) and random error (σ) were calculated at different correction threshold levels. The translational setup error and rotational setup error at the left-right (X axis), head-foot (Y axis) and front-back (Z axis) directions before and after radiotherapy were compared, which were expressed as Σ ± σ.Results:The pre-SBRT and post-SBRT translational setup errors were (0.14±0.27) cm and (0.07±0.19) cm, respectively ( P<0.001) in the X direction, (-0.05±0.33) cm and (0.00±0.19) cm, respectively ( P = 0.001) in the Y direction, (-0.13±0.19) cm and (-0.02±0.14) cm, respectively ( P = 0.012) in the Z direction. The pre-SBRT and post-SBRT rotational setup errors were (-0.31±0.76)° and (-0.09±0.34)°, respectively ( P < 0.001) in the X direction, (-0.13±0.88)° and (-0.07±0.36) °, respectively ( P < 0.001) in the Y direction, (0.10±0.51)° and (0.16±0.38)°, respectively ( P < 0.001) in the Z direction. Conclusions:CBCT correction could reduce Σ and σof the translational setup and rotational setup, increase the accuracy of SBRT based on VMAT-FFF for patients with spinal metastatic tumors.
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Objective:To compare the dosimetric differences between accelerated partial breast irradiation intensity modulated radiation therapy (APBI-IMRT) and whole breast irradiation with simultaneous integrated boost intensity modulated radiotherapy (WBI-SIB-IMRT) for early-stage breast cancer after breast-conserving surgery.Methods:A total of 35 patients with early-stage breast cancer in Jilin Province Cancer Hospital between July 2009 and December 2014 after breast-conserving surgery were enrolled. The targeted regions of APBI-IMRT and WBI-SIB-IMRT were created for each patient. The dosimetric difference comparison of the targeted region and normal tissues was evaluated by using dose volume histogram (DVH).Results:There was no significant difference in the dosimetric comparison of gross tumor volume (GTVtb) and planning gross tumor volume (PGTVtb) after correction of cumulative radiation effect (CRE) between WBI-SIB-IMRT group and APBI-IMRT group (both P > 0.05). The dose of clinical target volume (CTV) and planning target volume(PTV) in APBI-IMRT group was higher than that in WBI-SIB-IMRT group [CTV: (4 720±71) cGy vs. (3 889±79) cGy, t = 3.184, P = 0.027; PTV: (4 675±164) cGy vs. (3 807±199) cGy, t = 2.751, P = 0.032] after CRE correction. Compared with WBI-SIB-IMRT group, the dose of ipsilateral lung tissue and left heart tissue in APBI-IMRT group was decreased after CRE correction [(558.5±8.9) cGy vs. (1 304.9±34.4) cGy, t = -7.328, P = 0.001; (35.5±5.3) cGy vs. (843.0±41.5) cGy, t = -8.137, P = 0.001]. V 5/3.6 Gy, V 10/7.3 Gy, V 15/10.9 Gy, V 20/14.6 Gy, V 25/18.2 Gy and V 30/21.9 Gy of the ipsilateral lung and V 30/21.9Gy, V 40/29.2Gy of left heart in all breast cancer patients after two chemotherapy treatments had significant differences (all P = 0.001). Conclusion:Compared with WBI-SIB, APBI-IMRT can improve the dose distribution in target area and reduce the volume of high dose irradiation in organs at risk.
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Objective To evaluate the efficacy of accelerated partial breast irradiation ( APBI ) and whole breast irradiation ( WBI ) with simultaneous integrated boost ( SIB ) from the perspective of economics, and provide a reference for postoperative adjuvant therapy mode selection for early-stage breast cancer after breast-conserving surgery. Methods A total of 355 early-stage breast cancer patients who underwent APBI or WBI-SIB after breast-conserving surgery were evaluated on efficacy and cost-effectiveness, of which 177 patients received APBI, and 178 patients received WBI-SIB. Survival analysis was done according to treatment received. NCI-CTC 3.0 was used to score the toxicities. Breast aesthetic outcome were evaluated with Harris standards. Results Median follow-up was 42 months ( 5.8 -92.7 months) . The 3-year locoregional recurrence free survival( LRFS) rates in APBI group and WBI-SIB group were 98.2％ and 97.6％, distant metastasis free survival( DMFS) were 94.3％ and 93.7％, disease-free survival ( DFS) were 93.1％ and 91.6％, and overall survival 95.5％ and 94.3％, respectively, without statistically significant differences(P>0.05). Compared with WBI-SIB group, the acute reaction rates in APBI group decreased from 5. 6％ to 3.4％(χ2 =6.044, P <0. 05), and late reactions from 5.6％ to 2.3％ (χ2 =6.149, P<0. 05), while the cosmetic outcome improved from 88.8％ to 93.8％(χ2 =5.22, P<0. 05). Moreover, the processing average time was shortened by 26.5 d (χ2 =40.76, P<0. 05). Conclusions After breast-conserving surgery, the efficacy of APBI showed no difference from WBI-SIB with respect to 3-year local control, disease-free survival, and overall survival, but displayed a significantly better toxicity profile and cost-effectiveness ratio for early breast cancer patients. It can be used as a good radiotherapy model after breast-conserving surgery in early-stage breast cancer.
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Objective To explore the influence of the number and orientation of the beams on the optimization of IMRT plan.Methods Four IMRT plans were designed for 9 patients with cervical cancer,and 7 and 15 fields were applied.The 15-field plans had 30 segments and the 7-field plans had 55 segments.The initial beam angle degrees were 0° and 180°,respectively.Dose delivery time,MUs of plans,the dose distributions of the targets,organs at risk and normal tissues were analyzed and compared in the plans.Results Compared the plans with different beam directions under the same amount,no difference of the irradiation dosimetry in the target and organs at risk was found,except for irradiation dosimetry received by the 7-field 180° small intestine was about 4％ higher than the other three plans(F=6.164,P＜0.05).The terms of the volume of organs at risk got high dose irradiation(V40 and V30 of the rectum and bladder,V40 of the small intestine),which was similar in the 7-and 15-field plans.V20 and Dmean of organs at risk were significantly smaller(F=3.665-10.503,P＜0.05)in the 15-field plans.The 15-field plans needed a little longer treatment time(F=0.312,P＜0.05)and HI was slightly worse (F=12.933,P＜0.05),but the number of MUs was significantly reduced(F=4.650,P＜0.05).Conclusions Increasing the beam number will offset the negative impact of sub field reduction and get the similar dose distribution result.
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Objective To probe the influence of electron beam radiotherapy in different manners using different tissue equivalent boluses on skin and lung.Methods Adult female cavia cobayas were randomly divided into four groups as control group,fuU-time with bolus group,half-time with bolus group and without bolus group.Acute-irradiation animal models were established using electron beam in different manners with or without 0.5 cm tissue equivalent bolus.Pathological changes in lung,hair vesicle and fibroblast cell count were analyzed 40 clays after irradiation.Results The radiation dermatitis in the group with bolus was slighter than that of the group without bolus,but the radiation pneumonia was reverse.With bolus,the radiation dermatitis of haft-time group was slighter than that of full-time group.The injury repair of half-time group was more active than full-time group.Conclusions The treatment of haft-time bolus could protect lung without serious skin complications.
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This study sought to assess the biocompatibility of P(DA-SA)-Adriamycin, a new controlled-release chemotherapy system, in rabbit brain, and to examine its controlled release effect both in vitro and in vivo and its curative effects in vitro. The reaction of animal brain to the implanted P(DA-SA) or P(DA-SA)-Adriamycin was observed. The controlled-release profiles in phosphate buffer solutions and in rabbit brain were measured by UV spectrometry. Then, through flow cytometer, the rate of apoptosis in cultured glioma cells was tested. The reaction of rabbit brain to P(DA-SA) polymer was moderate and not significantly different from that to Gelfoam. The controlled-release rate of P(DA-SA)-Adriamycin in vitro and in vivo was stable and the duration of controlled-release of P(DA-SA)-Adriamycin spanned three weeks. The rate for apoptosis of glioma cells of P(DA-SA)-Adriamycin group was 69.9%, which was significantly higher than that of the control group. In conclusion, P (DA-SA)-Adriamycin controlled release chemotherapy system that bears curative effect has favorable controlled-release effect and good biocompatibility in rabbit brain. This system has potential value in treatment of malignant brain tumor.
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Animals , Rabbits , Antibiotics, Antineoplastic , Pharmacokinetics , Apoptosis , Brain , Metabolism , Decanoic Acids , Metabolism , Doxorubicin , Pharmacokinetics , Drug Carriers , Metabolism , Drug Implants , Materials Testing , Polyesters , Metabolism , Tumor Cells, CulturedABSTRACT
Objective To analyse the cause of constipation and evaluate the diagnostic value of colonic transit test and defecography for constipation diagnosis. Methods 110 cases with constipation were studied with colonic transit test and defecography. Results Abnormal colonic transit in 79 cases and defecography in 53 cases, overpassing the integrated analysis for the result of colonic transit test and defecography, the 40 cases were colonic inertia and 53 cases were function outlet obstruction. Conclusion The associated application of colonic transit test and defecography could be more accurate to differentiate constipations which are colonic inertia or function outlet obstruction and more specific the pathogeny of function outlet obstruction, to offer reliable foundation for the clinical cure.
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Objective To compare the pass rates of two primary hearing screening times and to determine the appropriate screening time.Methods The newborns born in 2004 and 2005 at our hospital were divided into two groups: group A and group B.Group A received hearing screening with distortion product otoacoustic emission(DPOAE) on the 3rd day after birth,while group B screened in one month after birth.The newborns who failed the initial screening were rescreened one month later.The babies with positive screening findings were referred to full auditory assessments.Results Group A(n=2 305) had pass rate 81.9% at the initial screening and 85.2% at rescreening.Group B(n=1 348) had pass rate 93.9%(?2=103.99,P