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Purpose@#The purpose of this study was to compare the survival and toxicities in cervical esophageal squamous cell carcinoma (CESCC) treated by concurrent chemoradiothrapy with either three-dimensional conformal radiotherapy (3D-CRT) or intensity-modulated radiotherapy (IMRT) techniques. @*Materials and Methods@#A total of 112 consecutive CESCC patients were retrospectively reviewed. 3D-CRT and IMRT groups had been analyzed by propensity score matching method, with sex, age, Karnofsky performance status, induction chemotherapy, and tumor stage well matched. The Kaplan-Meier method and Cox proportional hazards model were used for overall survival (OS) and progression-free survival (PFS). Toxicities were compared between two groups by Fisher exact test. @*Results@#With a median follow-up time of 34.9 months, the 3-year OS (p=0.927) and PFS (p=0.859) rate was 49.6% and 45.8% in 3D-CRT group, compared with 54.4% and 42.8% in IMRT group. The rates of grade ≥ 3 esophagitis, grade ≥ 2 pneumonitis, esophageal stricture, and hemorrhage were comparable between two groups, while the rate of tracheostomy dependence was much higher in IMRT group than 3D-CRT group (14.3% vs.1.8%, p=0.032). Radiotherapy technique (hazard ratio [HR], 0.09; 95% confidence interval [CI], 0.01 to 0.79) and pretreatment hoarseness (HR, 0.12; 95% CI 0.02 to 0.70) were independently prognostic of tracheostomy dependence. @*Conclusion@#No survival benefits had been observed while comparing IMRT versus 3D-CRT in CESCC patients. IMRT with fraction dose escalation and pretreatment hoarseness were considered to be associated with a higher risk for tracheostomy dependence. Radiation dose escalation beyond 60 Gy should be taken into account carefully when using IMRT with hypofractionated regimen.
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Objective To investigate the influence of degree of the injury in uterine junctional zone (JZ) of intrauterine adhesions (IUAs) patients on postoperative pregnancy outcomes by magnetic resonance imaging (MRI). Methods Design: Retrospective observational study. Setting: Navy General Hospital of PLA, Beijing. The study included ninety-two patients undergoing preoperative pelvic MRI from June 2011 to June 2014, and they were diagnosed as IUA by hysteroscopy, and hysteroscopic adhesiolysis was conducted under the guidance of abdominal ultrasound. All patients had tried to be pregnant for longer than six months. According to whether uterine junctional zone (JZ) was injured or not, the patients were divided into two groups: group A (JZ was normal) and group B (JZ was partly or completely injured). All patients were followed up with telephone comunication regarding postoperative pregnancy outcome within two weeks in August 2015. The difference of severity of IUAs and pregnancy outcome was compared. Results There were 51 and 41 IUAs cases in Group A and Group B, respectively. According to European Society of Gynecological Endoscopy (ESGE) classification of IUAs, the number of mild, moderate and severe IUA cases were 20, 24 and 7, respectively, in group A; and 10, 12 and 19, respectively, in group B. The proportion of severe IUA cases was significantly higher in group B than in group A (P=0.001). Forty-six of 92 IUAs cases had been pregnant, the pregnancy rate was 50%. Among them 4 had conceived twice. Twenty-one IUAs had given live birth (one had given birth to a pair of twins), and 10 were in pregnancy. The live-birth delivery rate was 42%, and the pregnancy loss rate was 38%. Thirty-one and fifteen IUAs had been pregnant in group A and group B respectively, the pregnancy rate was higher in group A than in group B (60.8% vs 36.6%, P=0.021). The live-birth delivery rate was higher in group A than in group B (47.1% vs 31.3%, P=0.365), while the pregnancy loss rate was higher in group B than in group A (29.4% vs 56.3%, P=0.117), but the difference was not statistically significant. Conclusions The severity of IUAs was associated with the degree of injury of uterine JZ. Especially, when JZ was completely injured, it was meant to have severe IUAs. For IUAs, injured uterine JZ may significantly decrease the postoperative pregnancy rate and live-birth delivery rate, and increase in the pregnancy loss rate. Evaluation of JZ may offer new perspectives to estimate the severity of IUA and the outlook of pregnancy. So it is recommended to evaluate the degree of injury of uterine JZ as an independent predictor for postoperative pregnancy outcome of IUAs. For severe IUAs, once JZ was extensively or completely injured, the outcome of pregnancy may be very poor.
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<p><b>OBJECTIVE</b>To study the impact of different planning target volume (PTV) margin settings on surface and superficial dose distribution and explore the resolution of high superficial dose when the target area is close to the surface during head and neck intensity-modulated radiotherapy (IMRT).</p><p><b>METHODS</b>A typical superficial target volume was designed in an circular neck phantom. Two experimental inverse IMRT plans were conducted with 8MV X ray, and in plan A, the superficial side of PTV margin ranged from 0 to 5 mm, while other side margins were 5 mm; in plan B, an suppositional machine dosimetry data for IMRT optimization was established in which the build-up dose was eliminated, and this machine data was used to optimize the inverse IMRT plan followed by recalculation of the planned dose distribution with the actual clinical machine dosimetry data. The variation of the surface and superficial dose resulting from set-up error and the dose distribution to CTV were compared. The adequate PTV margin was analyzed when the CTV approached the surface.</p><p><b>RESULTS</b>In plan A, the high dose greater than the prescribed dose was found in the surface and superficial region when the superficial sparing distance was between the surface and PTV d<3 mm, and the 3 mm set-up margin increased this superficial dose remarkably. Reducing the superficial side of PTV margin lowered the high superficial dose effectively and allowed maintenance of the prescribed dose to the CTV. To avoid reduction of the dose to the CTV to below 95% of the prescribed dose, the superficial side of PTV margin should be greater than 1 mm. Plan B effectively lowered the surface doses and maintained the prescribed dose to the CTV.</p><p><b>CONCLUSIONS</b>With appropriate techniques for optimizing inverse IMRT, more homogeneous superficial dose can be achieved.</p>
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Humains , Simulation numérique , Tumeurs de la tête et du cou , Radiothérapie , Lésions radiques , Radioprotection , Méthodes , Planification de radiothérapie assistée par ordinateur , Méthodes , Radiothérapie conformationnelle avec modulation d'intensité , Méthodes , Normes de référence , Peau , Effets des rayonnementsRÉSUMÉ
<p><b>BACKGROUND AND OBJECTIVE</b>The planning dose distribution of intensity-modulated radiation therapy (IMRT) has to be verified before clinical implementation. The commonly used verification method is to measure the beam fluency at 0 degree gantry angle with a 2-dimensional (2D) detector array, but not the composite dose distribution of the real delivery in the planned gantry angles. This study was to investigate the angular dependence of a 2D diode array (2D array) and the feasibility of using it to verify the composite dose distribution of IMRT.</p><p><b>METHODS</b>Angular response of the central detector in the 2D array was measured for 6 MV X-ray, 10 cmx10 cm field and 100 cm source axis distance (SAD) in different depths. With the beam incidence angle of 0-60 degrees, at intervals of 10 degrees, and inherent buildup of the 2D array (2 g/cm2), the array was irradiated and the readings of the central diode were compared with the measurement of thimble ionization chamber. Using a combined 30 cmx30 cmx30 cm phantom which consisted of solid water slabs on top and underlying the 2D array, with the diode detectors placed at 8 g/cm2 depth, measurements were taken for beam angles of 0 degrees-180 degrees at intervals of 10 degrees and compared with the calculation of treatment planning system (TPS) that pre-verified with ion chamber measuring.</p><p><b>RESULTS</b>Differences between the array detector and thimble chamber measurements were greater than 1% and 3.5% when the beam angle was larger than 30 degrees and 60 degrees, respectively. The measurements in the combined phantom were different from the calculation as high as 20% for 90 degrees beam angle, 2% at 90 degrees+/-5 degrees and less than 1% for all the other beam angles.</p><p><b>CONCLUSIONS</b>The 2D diode array is capable of being used in composite dose verification of IMRT when the beam angles of 90 degrees+/-5 degrees and 270 degrees+/-5 degrees are avoided.</p>
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Calibrage , Études de faisabilité , Accélérateurs de particules , Fantômes en imagerie , Radiométrie , Dosimétrie en radiothérapie , Planification de radiothérapie assistée par ordinateur , Radiothérapie conformationnelle avec modulation d'intensité , MéthodesRÉSUMÉ
<p><b>BACKGROUND AND OBJECTIVE</b>To ensure the accuracy of dose calculation for radiation treatment plans is an important part of quality assurance (QA) procedures for radiotherapy. This study evaluated the Monitor Units (MU) calculation accuracy of a third-party QA software and a 3-dimensional treatment planning system (3D TPS), to investigate the feasibility and reliability of independent verification for radiation treatment planning.</p><p><b>METHODS</b>Test plans in a homogenous phantom were designed with 3-D TPS, according to the International Atomic Energy Agency (IAEA) Technical Report No. 430, including open, blocked, wedge, and multileaf collimator (MLC) fields. Test plans were delivered and measured in the phantom. The delivered doses were input to the QA software and the independent calculated MUs were compared with delivery. All test plans were verified with independent calculation and phantom measurements separately, and the differences of the two kinds of verification were then compared.</p><p><b>RESULTS</b>The deviation of the independent calculation to the measurements was (0.1 +/- 0.9)%, the biggest difference fell onto the plans that used block and wedge fields (2.0%). The mean MU difference between the TPS and the QA software was (0.6 +/- 1.0)%, ranging from -0.8% to 2.8%. The deviation in dose of the TPS calculation compared to the measurements was (-0.2 +/- 1.7)%, ranging from -3.9% to 2.9%.</p><p><b>CONCLUSIONS</b>MU accuracy of the third-party QA software is clinically acceptable. Similar results were achieved with the independent calculations and the phantom measurements for all test plans. The tested independent calculation software can be used as an efficient tool for TPS plan verification.</p>
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Algorithmes , Fantômes en imagerie , Contrôle de qualité , Radiométrie , Méthodes , Dosimétrie en radiothérapie , Planification de radiothérapie assistée par ordinateur , Méthodes , LogicielRÉSUMÉ
<p><b>OBJECTIVE</b>To investigate the feasibility and efficiency of jaws-only intensity-modulated radiation therapy (JO-IMRT) in treatment of nasopharyngeal carcinoma (NPC) using direct aperture optimization (DAO) technique and the independent jaws of linear accelerator.</p><p><b>METHODS</b>Both JO-IMRT and MLC-IMRT were planed in 10 NPC cases. The differences in the target coverage and dose uniformity, as well as the total monitor units and delivery times of the two IMRT plans were compared.</p><p><b>RESULTS</b>All the tested plans met the clinical requirement of the designed simplified IMRT (sIMRT). The conformal index (CI) of JO-IMRT and MLC-IMRT were 0.941±0.015 and 0.981±0.013, respectively (P<0.001), showing a minor superiority of MLC-IMRT. While controlling the total segment numbers to approach the limitation of sIMRT, the two therapies showed a total MU of 474.3 and 419.6 (P<0.05) with delivery times of 8.0 and 7.5 min (P<0.01), respectively. The efficiency of JO-IMRT was slightly lower than that of MLC-IMRT.</p><p><b>CONCLUSION</b>JO-IMRT can meet the sIMRT requirement in NPC treatment, and is feasible as an alternative treatment modality for the centers not equipped with MLC in their accelerators.</p>
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Humains , Carcinomes , Études de faisabilité , Tumeurs du rhinopharynx , Radiothérapie , Accélérateurs de particules , Planification de radiothérapie assistée par ordinateur , Méthodes , Radiothérapie conformationnelle avec modulation d'intensité , MéthodesRÉSUMÉ
Objective To analyse the preliminary clinical results of intensity modulated radiation therapy (IMRT) for 122 untreated nasopharyngeal carcinoma (NPC)pafients.Methods 122 NPC pa- tients received IMRT alone from Feb.2001 to Jun.2004,with 31 females and 91 males,and a median age of 45 years(range 25-66).According to the Fuzhou Stage Classification,there were StageⅠ11 patients, StageⅡ34,StageⅢ62,and StageⅣa 15.IMRT was carried out using an inverse planning system (COR- VUS 5.0,Peacock plan) developed by the NOMOS Corp.The treatment was given with the Multi-leaf Inten- sity Modulating Collimator (MIMIC) using a slice-by-slice arc rotation approach.The prescription dose was 68 Gy/30f to the nasopharynx gross tumor volume (GTV_(nx)),60-66 Gy/30f to positive neck lymph nodes (GTV_(nd)),60 Gy/30f to the first clinical target volume (CTV_1) and 54 Gy/30f to the second clinical target volume (CTV_2).Kaplan-Meier method was used to calculate the overall survival rate (OS),distant metas- tasis-free survival rates (DMFS),and local-regional control rates from the last date of therapy.Log-rank test was used to detect the difference between groups.Results The median follow-up time was 20 months ( range 6 to46 months).The 1-,2-,and 3-year OS was 95.2%,91.4%,85.1%,DMFS was 91.9%, 88.6%,85.6%,and the local-regional control rates was 96.5%,93.2%,93.2%,respectively.Statistics of the local control rate was insignificant either for advanced T(T3+T4) stage or early T(T1+T2) stage diseases(P=0.148).The 2-year regional control rate was insignificant either for patients with N(+) or N (-),but the 2-year DMFS was significant both for patients with N(+) and N(-)lesions(P=0.004).For 17 patients who failed,there were two with residual disease and one with recurrence at the primary site (17.6%),three patients in the neck (17.6%),twelve patients (70.6%) in distant metastases.Conclu- sions Intensity modulated radiation therapy does provide excellent local-regional control for untreated NPC, especially in patients with advanced T stage or N(+) lesion.Distant metastasis is the main cause of failure. N (+) is significantly correlated with distant metastasis.
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Objective Objective To verify the accuracy of dose calculation and the precision of beam modeling in a Pinnacle three-dimension treatment planning system(TPS).Methods Based on the photon beam model data of a Varian 600C Linac,output factor verification and 12 tests were carried out ac- cording to the recommendation of Netherlands Commission on Radiation Dosimetry(NCS).The results of ion chamber measurement and TPS calculation at selected points were compared.Deviation and confidence limit were used to evaluate dose calculation accuracy.Results The Pinnacle TPS had a high precision of dose calculation when compared with the measurement data.Deviation of calculated output factors was<1% on all opening patrols,and was<3% on wedged portal except one with the size of 15 cm?40 cm and angled 60?.The results of 12 tests were in accordance with the criteria of NCS recommendation,with maximum av- erage deviation<1%.The overall accuracy is better than those of other TPS reported in the literature. Conclusions Dose verification is a prerequisite before a three-dimension treatment planning system is used in the clinical practice.Pinnacle treatment planning system installed in our institute is reasonably acceptable and satisfactory.
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<p><b>OBJECTIVE</b>To evaluate the feasibility, toxicity and tumor control of intensity modulated radiation therapy (IMRT) for recurrent nasopharyngeal carcinoma.</p><p><b>METHODS</b>Fourty-nine patients (Karnofsky performance status (KPS) >or= 80) with local-regional recurrence in the nasopharynx were treated with full course IMRT. Three patients with cervical lymph node metastasis (N1 2 and N3 1) were further supplemented with 5 to 6 courses of chemotherapy (Cisplatin + 5-Fu) after IMRT.</p><p><b>RESULTS</b>The results of treatment plan showed that the mean dose of covering gross tumor volume (GTV) (D(95)) in the nasopharynx was 68.09 Gy and the mean volume of GTV (V(95)) receiving the 95% dose was 98.46%. The mean dose of GTV, clinical target volume CTV1 and CTV2 in the targets were 71.40 Gy, 63.63 Gy and 59.81 Gy. The median follow-up time was 9 months (range 3 to 16 months). The local-regional progression-free survival was 100% with local-regional residual disease in 3 (6.1%) cases but was complicated with nasopharyngeal mucosa necrosis in 14 (28.6%) cases after IMRT.</p><p><b>CONCLUSION</b>Intensity modulated radiation therapy, as a re-treatment option for recurrent nasopharyngeal carcinoma, is able to improve the tumor target coverage and spare the adjacent critical structures. As high dose IMRT can result in radio-necrosis of nasopharyngeal mucosa, the prescription dose of GTV should be suitably decreased to 60 - 65 Gy.</p>
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Adulte , Sujet âgé , Femelle , Humains , Mâle , Adulte d'âge moyen , Carcinome épidermoïde , Anatomopathologie , Radiothérapie , Études de suivi , Métastase lymphatique , Tumeurs du rhinopharynx , Anatomopathologie , Radiothérapie , Récidive tumorale locale , Radiothérapie , Stadification tumorale , Lésions radiques , Anatomopathologie , Dosimétrie en radiothérapie , Planification de radiothérapie assistée par ordinateur , Radiothérapie conformationnelle , MéthodesRÉSUMÉ
Objective Study the ideal drug to treat age depen de nt epileptic ncephalopathy (ADEE) in earlier period. Methods fi fty-four patients with ADEE were studyed.21 cases used with single topiramate(T PM) as initial treatment and 27 cases used with TPM and antiepileptic drug(AEDs ) .Results Seizure was fully controlled in 11 patients with TPM m onotherapy and in 4 patients with TPM as adjunction.The differences was signif icant(P
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To investigate the application of a recently developed metallic oxide semiconductor field effect transistor(MOSFET)detector for use in vivo desimetry.Methods The MOSFET detector was calibrated for X-ray beams of 8 MV and 15 MV,as well as electron beams with energy of 6,8,12 and 18 MeV.The dose linearity of the MOSFET detector was investigated for the doses ranging from 0 up to 50 Gy using 8 MV X-ray beams.Angular effect was evaluated as well in a cylindrical PMMA phantom by changing the beam entrance angle every 15?clockwise.The MOSFET detector was then used for a breast cancer patient in vivo dose measurement, after the treatment plan was verified in a water phantom using a NE-2571 ion chamber,in vivo measurements were performed in the first and last treatment,and once per week during the whole treatment.The measured doses were then compared with planning dose to evaluate the accuracy of each treatment.Results The MOSFET detector represented a good energy response for X-ray beams of 8 MV and 15 MV,and for electron beams with energy of 6 MeV up to 18 MeV.With the 6 V bias,Dose linearity error of the MOSFET detector was within 3.0% up to approximately 50 Gy,which can be significantly reduced to 1% when the detector was calibrated before and after each measdurement.The MOSFET response varied within 1.5% for angles firm 270?to 90?.However,maximum error of 10.0% was recorded comparing MOSFET response between forward and backward direction.In vivo mea surement for a breast cancer patient using 3DCRT showed that,the average dose.deviation between measurement and calculation was 2.8%,and the maximum error was less then 5.0%.Conclusions The new MOSFET detector,with its advantages of being in size,easy use,good energy response and dose linearity,can be used for in vivo dose measurement.
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Objective To compare three kinds of irradiation treatment plans for cervical and upper thoracic esophageal cancer,in order to arrived at proper decision for the patient.Methods From February 2001 to June 2004,43 such patients were studied with three different simulated treatment plans made including conformal plan,conventional four-field plan and conventional two-field plan for every one.All plans were evaluated with iso- dose curve and dose-volume histogram.Results GTV on 95% isodose curve was 99.5%,98.2% and 87.4% in conforaml plan,conventional four-field plan and conventional two-field plan,respectively;PTV_1 and PTV_2 on 95% isodose with 97.8%,97.2%,94.8% and 95.8%,86.6%,73.7%.The volume of>20 Gy dose of left lung accepted was 18.6%,17.2% and 32.3%,in conformal plan,conventional four-field plan and conventional two-field plan,respectively;the right lung received 20.5%,19.9% and 35.5%.Conclusions Conformal plan is the best in radiotherapy,as it can provide ideal dose distribution of irradiated target with adequate protection of the normal tissues.Conventional four-field plan,being easy to carry out,can replace the conformal plan in most situations.Conventional two-field has the most uneven dose distribution and largest lung volume irradiated.