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Objective:To evaluate the effect of radical image-guided radiotherapy (IGRT) on the target dose in cervical cancer and investigate the appropriate application mode.Methods:Twenty patients with cervical cancer treated with helical tomotherapy (HT) in Seventh Medical Center of PLA General Hospital from 2012 to 2016 were selected. A megavoltage CT (MVCT) scan was performed before each treatment. The obtained MVCT images were used for dose parameter in the adaptive module of HT to obtain the actual dose (Plan 1) and the non-image-guided dose parameter was simulated (Plan 2). Each single dose distribution and the corresponding fused CT images were transferred to the software Mimvista 6.5 to obtain the total radiation dose parameter by dose superposition.Results:The motion of CTV, uterus and GTV in Plan 2 was significantly larger than that of Plan 1(all P<0.05), and the largest changes were seen in the ventrodorsal and uterine direction. The V 45Gy, V 50Gy, D 98% and D mean of CTV and uterus and V 50Gy of GTV in Plan 2 were significantly decreased compared with those in Plan 1(all P<0.05). The left-right motion of Plan 1 was negatively correlated with D 2% and D 98% of CTV and uterus (both P<0.05). The head-foot motion was negatively associated with V 45Gy and V 50Gy of GTV (both P<0.05). The ventrodorsal motion was negatively correlated with D 98% of uterus ( P<0.05). The left-right motion of Plan 2 was negatively correlated with D 2% of CTV and V 50Gy of uterus (both P<0.05). The head-foot motion was negatively associated with D 98% of CTV, and D 98%, D mean, V 45Gy and V 50Gy of uterus (all P<0.05). The ventrodorsal motion was negatively correlated with D 98% of CTV, D 98%, D mean, V 45Gy and V 50Gy of uterus, and D mean and V 45Gy of GTV (all P<0.05). Conclusions:In intensity-modulated radiotherapy for cervical cancer, the uterine body displacement is large and the low CTV area is mainly located in the uterine body. IGRT can significantly reduce the dosimetric deviation induced by organ movement.
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Objective@#To evaluate the prognostic factors of T1-2N0M0 esophageal squamous cell carcinoma (ESCC) treated with definitive radiotherapy.@*Methods@#The clinical data of 196 patients with T1-2N0M0 ESCC who were treated with definitive radiotherapy in 10 hospitals were retrospectively analyzed. All sites were members of Jing-Jin-Ji Esophageal and Esophagogastric Cancer Radiotherapy Oncology Group (3JECROG). Radiochemotherapy were applied to 78 patients, while the other 118 patients received radiotherapy only. 96 patients were treated with three-dimensional conformal radiotherapy (3DCRT) and 100 treated with intensity-modulated radiotherapy (IMRT). The median dose of plan target volume(PTV) and gross target volume(GTV) were both 60 Gy. The median follow-up time was 59.2 months. Log rank test and Cox regression analysis were used for univariat and multivariate analysis, respectively.@*Results@#The percentage of normal lung receiving at least 20 Gy (V20) was (18.65±7.20)%, with average dose of (10.81±42.05) Gy. The percentage of normal heart receiving at least 30 Gy (V30) was (14.21±12.28)%. The maximum dose of exposure in spinal cord was (39.65±8.13) Gy. The incidence of radiation pneumonia and radiation esophagitis were 14.80%(29/196) and 65.82%(129/196), respectively. The adverse events were mostly grade 1-2, without grade 4 toxicity. Median overall survival (OS) and progression-free survival (PFS) were 70.1 months and 62.3 months, respectively. The 1-, 3- and 5-year OS rates of all patients were 75.1%、57.4% and 53.2%, respectively. The 1-, 3- and 5-year PFS rates were 75.1%、57.4% and 53.2%, respectively. Multivariate analysis demonstrated that patients′age (HR=1.023, P=0.038) and tumor diameter (HR=1.243, P=0.028)were the independent prognostic factors for OS, while tumor volume were the independent prognostic factor for PFS.@*Conclusions@#Definitive radiotherapy is a promising therapeutic method in patients with T1-2N0M0 ESCC. Patients′ age, tumor diameter and tumor volume may impact patients′ prognosis.
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Objective:The aim of this study was to investigate the relationship between monocyte to high density lipoprotein-cholesterol ratio (MHR) and the infection, severity, and prognosis of diabetic foot ulcer.Methods:A retrospective cohort study of 194 patients with diabetic foot ulcer between September 2016 and August 2018 was conducted at the First Affiliated Hospital of University of South China. The clinical data, glucose and lipids metabolism, renal function, nutritional status, coagulation function, and severity of infection, severity, ischemic, and diagnosis were recorded. The rates of healed ulcer, amputation, and mortality were followed for six months.Results:The higher MHR levels of diabetic foot ulcer patients were accompanied with the higher Wagner grade, infection grade, severity of lower extremity ischemia, and proportion of adverse outcomes ( P trend<0.05). MHR and many traditional risk factors of diabetic foot ulcer (white blood cell count, C-reactive protein, albumin, estimated glomerular filtration rate, and ankle brachial index) were significantly correlated (all P<0.05). After adjustment for potential confounders, multivariate logistics regression analysis showed that MHR levels were positively associated with the occurrence of adverse outcomes [odds ratio ( OR) for the highest quartile vs lowest quartile, 1.52 (95% CI 1.08-3.08), P<0.05]. The receiver operating characteristic (ROC) curve analysis showed that area under the curve (AUC) of high MHR, high C-reactive protein, and low albumin for predicting the occurrence of adverse outcomes in diabetic foot ulcer patients were 0.674 (95% CI 0.581-0.747), 0.703(95% CI 0.615-0.772), and 0.667(95% CI 0.569-0.734), respectively. Conclusion:Elevation of MHR in diabetic foot ulcer patients are positively correlated with the grading of Wagner classification, and the severity of infection and ischemia, and seriously affects the prognosis of patients, suggesting that more attention should be paid to the MHR.
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Objective:To evaluate the effect of definitive radiotherapy with different doses on overall survival (OS) and identify the prognostic factors of patients with non-metastatic esophageal squamous cell carcinoma (ESCC).Methods:Clinical data of 2 344 ESCC patients treated with definitive radiotherapy (RT) alone or chemoradiotherapy from 2002 to 2016 in 10 hospitals were collected and analyzed retrospectively. After the propensity score matching (PSM)(1 to 2 ratio), all patients were divided into the low-dose group (equivalent dose in 2 Gy fractions, EQD 2Gy<60 Gy; n=303) and high-dose group (EQD 2Gy≥60 Gy; n=606) based on the dose of radiation. Survival analysis was conducted by Kaplan- Meier method. Multivariate prognostic analysis was performed by Cox′s regression model. Results:The median follow-up time was 59.6 months. After the PSM, the 1-, 3- and 5-year overall survival (OS) rate was 66.5%, 34.7%, 27.2% in the low-dose group, 72.9%, 41.7% and 34.7% in the high-dose group, respectively ( P=0.018). The 1-, 3-and 5-year progression-free survival rate was 52.2%, 27.2%, 23.1% in the low-dose group, 58.3%, 38.1% and 33.9% in the high-dose group, respectively ( P=0.001). The outcomes of univariate analysis indicated that cervical/upper esophagus location, early (stage Ⅱ) AJCC clinical stage, node negative status, tumor length ≤5 cm, receiving intensity-modulated radiation therapy (IMRT), receiving concurrent chemotherapy and EQD 2Gy≥60 Gy were closely associated with better OS (all P<0.05). Multivariable analysis demonstrated that tumor location, regional lymph node metastasis, concurrent chemotherapy and EQD 2Gy were the independent prognostic factors for OS (all P<0.05). Conclusion:Three-dimensional conformal or IMRT with EQD 2Gy≥60 Gy yields favorable survival outcomes for patients with locally advanced ESCC.
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Objective:To investigate the expression change of blood plasma miRNA-210 (miR-210) in blood plasma for patients with esophageal squamous cell carcinoma (ESCC) before and after radiotherapy and its effect on cell proliferation, cycle, apoptosis of ESCC cells in vitro.Methods:The blood specimens from 22 patients with newly diagnosed ESCC (ESCC group) before and after radical radiotherapy between December 2013 and March 2015 in Linyi People's Hospital of Shandong Province as well as 15 healthy controls (the healthy control group) were collected. miRNA-21 (miR-21) was treated as the positive controls. The real-time polymerase chain reaction (RT-PCR) was used to detect the expression level of miR-210 and miR-21 in blood plasma before and after radiotherapy for patients, and the expression of miR-21 in ESCC Eca109 cells at normoxia and hypoxia time. The cell proliferation, cycle and apoptosis of Eca109 cells in untransfected group (the blank control group), miR-21 transfected mimics negative control RNA group (negative control group) and miR-210 transfected mimics RNA group (miR-210 group) were detected by using EdU cell proliferation assay and flow cytometry.Results:A total of 59 plasma samples from ESCC group and the healthy control group were collected. The relative expression level [median ( P25, P75)] of blood plasma miR-210 and miR-21 in ESCC group before radiotherapy was higher than that in the healthy control group, and the difference was statistically significant [4.04×10 -4 (2.06×10 -4, 6.68×10 -4) vs. 0.54×10 -4 (0.28×10 -4, 0.77×10 -4), 397.07×10 -4 (181.77×10 -4, 742.93×10 -4) vs. 127.43×10 -4 (21.97×10 -4, 184.65×10 -4); U value was 37.0, 49.0, respectively, all P < 0.01]. The expression level of miR-210 and miR-21 before radiotherapy in ESCC group was not related with tumor location and differentiation degree (all P > 0.05). After the radical radiotherapy one week later, the relative expression level of miR-210 and miR-21 in blood plasma of ESCC group was 65.33×10 -4 (22.15×10 -4, 160.87×10 -4), 437.23×10 -4 (327.18×10 -4, 749.09×10 -4), respectively, which was higher compared with that before radiotherapy ( U value was 32.0, 154.0, respectively, both P < 0.05), and the increase of miR-210 was more significant. The expression level of miR-210 after hypoxic cultured Eca109 cells for 12 h was increased compared with the normal oxygen with the peak value 12 h later, and the difference was statistically significant ( P < 0.01). EdU cell proliferation assay showed that the Eca109 cell proliferative activity after transfection of 24 h and 48 h in miR-210 group was decreased compared with the negative control group and the blank control group, and the difference was statistically significant (all P < 0.01). Flow cytometry analysis showed that the proportion of G 2/M phase of Eca109 cells in miR-210 group after transfection of 24 h was increased compared with the negative control group and the blank control group, and the difference was statistically significant ( P < 0.05). After transfection of 48 h, the increased proportion in G 2/M phase was more obvious ( P <0.01); there was no statistically difference in the apoptotic cell proportion among three groups after transfection of 24 h and 48 h (all P > 0.05). Conclusions:miR-210 is highly expressed in the blood plasma of ESCC patients, especially the significant increase in the expression level of miR-210 in blood plasma after radical radiotherapy. miR-210 is highly expressed in hypoxic ESCC Eca109 cells. The overexpression of miR-210 can inhibit cell proliferation and its mechanism may be related with cell arrest in G 2/M phase.
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Objective@#To explore the relationship between serum C1q and tumor necrosis factor related protein 6(CTRP6) level and insulin resistance in patients with newly diagnosed type 2 diabetes mellitus (T2DM).@*Methods@#A total of 167 patients with newly diagnosed T2DM in the outpatient department of our hospital were recruited from April 2016 to March 2017 and 165 subjects with normal glucose tolerance were used as the control group. The concentrations of CTRP6, interleukin 6 (IL-6), monocyte chemoattractant protein-1 (MCP-1), and tumor necrosis factor α (TNF-α) were determined by ELISA.@*Results@#Circulating CTRP6 level was significantly higher in T2DM group than that in control group [(652.54±132.57) vs (521.28±119.93)μg/L, P<0.01] after adjusting age and body mass index (BMI). Overweight/obese subjects revealed higher CTRP6 levels compared with those in lean individuals. In addition, circulating CTRP6 level was positively correlated with BMI, waist circumference, fasting plasma glucose, postprandial 2h plasma glucose, HbA1C, fasting insulin, homeostasis model assessment insulin resistance index (HOMA-IR), triglyceride (TG), IL-6, MCP-1, highly sensitive C-reactive protein (hs-CRP), and TNF-α, while it was inversely correlated with high-density lipoprotein-cholesterol(P<0.01). Multivariate linear regression analysis showed that TG, HOMA-IR, and IL-6 were independent factors for CTRP6 level. After adjusting for potential confounders, CTRP6 remained an independent risk factor for T2DM. Trend test showed that the increase in CTRP6 level was significantly linear with the occurrence of T2DM. The analysis of receiver operating characteristic curves revealed that the area under the curve for circulating CTRP6 to predict T2DM was 0.730.@*Conclusions@#CTRP6 may be associated with insulin resistance.
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Objective To explore the relationship between serum C1q and tumor necrosis factor related protein 6 ( CTRP6 ) level and insulin resistance in patients with newly diagnosed type 2 diabetes mellitus (T2DM). Methods A total of 167 patients with newly diagnosed T2DM in the outpatient department of our hospital were recruited from April 2016 to March 2017 and 165 subjects with normal glucose tolerance were used as the control group. The concentrations of CTRP6, interleukin 6 (IL-6), monocyte chemoattractant protein-1 ( MCP-1), and tumor necrosis factor a( TNF-α) were determined by ELISA. Results Circulating CTRP6 level was significantly higher in T2DM group than that in control group [(652.54 ± 132.57) vs ( 521.28 ± 119.93) μg/L, P＜0.01] after adjusting age and body mass index (BMI). Overweight/obese subjects revealed much higher CTRP6 levels compared with those in lean individuals. In addition, circulating CTRP6 level was positively correlated with BMI, waist circumference, fasting plasma glucose, postprandial 2h plasma glucose, HbA1C, fasting insulin, homeostasis model assessment insulin resistance index ( HOMA-IR), triglyceride ( TG), IL-6, MCP-1, highly sensitive C-reactive protein ( hs-CRP ), and TNF-α, while it was inversely correlated with high-density lipoprotein-cholesterol ( P＜0.01). Multiple linear regression analysis showed that TG, HOMA-IR, and IL-6 were independent factors for CTRP6 level. After adjusting for potential confounders, CTRP6 remains an independent risk factor for T2DM. Trend detection showed that the increase in CTRP6 level was significantly linear with the occurrence of T2DM. The analysis of receiver operating characteristic curves revealed that the area under the curve for circulating CTRP6 to predict T2DM was 0.730. Conclusions CTRP6 may be associated with insulin resistance.
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Objective To retrospectively analyze the effect of tumor length on the prognosis in stage Ⅱ/Ⅲ esophageal squamous cell carcinoma (ESCC) patients treated with definitive radiotherapy and to evaluate the role of tumor length in clinical stage for non-operative ESCC patients.Methods The data of 2 086 ESCC patients who were treated with definitive radiotherapy from 2002 to 2016 in 10 hospitals (3JECROG) were analyzed.The effect of tumor length on overall survival (OS) was analyzed and stratified analysis of tumor length was done in different stages of ESCC.Results The median OS and median progression-free survival (PFS) time of the whole group were 25.6 months and 18.2 months respectively.The Cox multivariate analysis showed that treatment moda,aga,alinical stage and tumor length were independent prognostic factors.The median,1-,3-,and 5-year OS were 28.9 months,77.3％,45.0％,and 36.3％ versus 21.9 months,69.9％,37.9％,and 28.1％ for patients with ≤ 5 cm and patients ＞ 5 cm respectively (P＜0.05).For stage Ⅱ patienta,abe median OS were 42.1 and 38.9 months respectively in ≤ 5 cm group and＞5 cm group (P=0.303).And for stage Ⅲ patienta,abe median OS were 23.9 and 19.3 months respectively in ≤5 cm group and＞5 cm group (P＜0.001).The median OS with N1was 24.1 and 18.4 montha,aespectively in ≤5 cm group and＞5 cm group (P＜0.001).Conclusions The tumor length was an independent prognostic factor for stage Ⅱ/Ⅲ patients treated definitive radiotherapy.The tumor length may be helpful in clinical staging of ESCa,aspecially for stage Ⅲ and N1.
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Objective To compare the therapeutic effects between three-dimensional conformal radiotherapy (3DCRT) and intensity-modulated radiotherapy (IMRT) in patients with stage Ⅱ/Ⅲ esophageal cancer and investigate the prognostic factors.Methods Medical record of 2 132 patients with stage Ⅱ/Ⅲ esophageal cancer who underwent definitive radiotherapy with/without chemotherapy in 10 hospitals from January 2002 to December 2016 from were retrospectively analyzed.Among these patients,37.9％ of them were aged ≥ 70 years,33.9％ with neck and upper esophageal tumors and 66.1％ with middle and lower esophageal and borderline tumors.The median gross tumor volume (GTV) and lymph node gross tumor volume (GTVnd) was 41.6 cm3.Among them,32％ were stage Ⅱ] and 68％ were stage Ⅲ.A total of 723 patients received 3DCRT and 1 409 cases received IMRT.Patients received an equivalent dose in 2 Gy (EQD2) ≥ 60 Gy accounted for 86.1％,and 41.1％ of them received concurrent chemoradiotherapy.Results The median follow-up time was 60.8 months.The 1-,3-and 5-year overall survival (OS) of all patients was 73.9％,41.7％ and 32.6％,and the 1-,3-and 5-year progression-free survival (PFS) was 62.2％,37.3％ and 32％,respectively.Multivariate analysis demonstrated that age,primary tumor location,clinical stage,tumor target volume,EQD2 and concurrent chemoradiotherapy were the independent prognostic factors for OS.Age,primary tumor location,clinical stage,tumor target volume and EQD2 were the independent prognostic factors for PFS.The OS and PFS did not significantly differ among the low-risk,low-/moderate-risk,moderate-/high-risk and high-risk groups according to age≥70 years,tumor diameter＞5 cm,tumor volume ≥41.6 cm3 and stage Ⅲ (P＜0.001).After the propensity score matching (PSM) method,neither 3DCRT nor IMRT yielded significant advantages in OS or PFS (P=0.971;P=0.658).However,IMRT tended to yield survival benefits in low-risk patients (P=0.125).Conclusions Both 3DCRT and IMRT yield relatively high OS rate in patients with stage Ⅱ/Ⅲ esophageal cancer.The prognosis model established in this investigation can properly predict the survival of patients.Low-risk patients tend to obtain survival benefits from IMRT.
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Objective To evaluate the survival and prognostic factors of esophageal cancer treated with definitive ( chemo ) radiotherapy by applying novel radiation techniques including three-dimensional conformal radiotherapy (3DCRT) or intensity-modulated radiotherapy (IMRT). Methods Clinical data of 2762 patients with non-operated esophageal squamous cell carcinoma who underwent definitive ( chemo ) radiotherapy from 2002 to 2016 in 10 hospitals were retrospectively analyzed.The prognostic factors were also identified and analyzed. Results The median follow-up time was 60. 8 months. The 1-, 2-, 3-and 5-year overall survival (OS) of all patients was 71. 4％,48. 9％,39. 3％,and 30. 9％,respectively.The 1-,2-,3-and 5-year progression-free survival (PFS) was 59.5％,41.5％,35.2％,and 30％,respectively.The median survival was 23 months.The median time to progression was 17. 2 months.Multivariate analysis demonstrated that age, primary tumor location, clinical stage, tumor target volume, EQD2 and treatment mode were the independent prognostic factors for OS.Primary tumor location,clinical stage,tumor target volume and EQD2 were the independent prognostic factors for PFS. Conclusions In this first large-scale multi-center retrospective analysis of definitive ( chemo) radiotherapy for esophageal squamous cell carcinoma in China, the 5-year OS of patients with esophageal squamous cell carcinoma is significantly improved by 3DCRT, IMRT combined with chemotherapy drugs. However, the findings remain to be validated by prospective clinical trials with high-level medical evidence.
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Objective To analyze the changes in volume and the planning volume of the bladder and rectum during helical tomotherapy (HT) treatment for cervical cancer,and to evaluate the impacts of bladder and rectum filling on their dosimetric parameters.Methods Twenty patients with cervical cancer who received HT in our hospital from 2012 to 2016 were enrolled as subjects.Before treatment,megavolt computed tomography (MVCT) and registration of planning CT images were preformed to recalculate the dose distribution,delineate the target volume,and measure the volume and position of the bladder and the rectum.Each MVCT image and the corresponding single dose were obtained by dose reconstruction using the Planned Adaptive module in HT planning workstation.The fused MVCT images and the corresponding single dose for each MVCT were loaded to MIM Maestro software 6.0 for dose stacking.The obtained total radiation dose was compared with that obtained by kilovolt CT.Between-group comparison was made by paired t-test or analysis of variance.Results If the volume change in the bladder was more than 400 ml or the rate of volume change was higher than 60％,the displacements of the bladder centroid toward the foot and dorsal sides were significantly increased;the Dmean and V50 were significantly increased (P＜0.05).If the volume change in the rectum was more than 30 ml or the rate of volume change was higher than 30％,the displacements of the rectum centroid toward the head and ventral sides were significantly increased;the V45 and V50 for the rectum were significantly increased (P＜0.05).Conclusions Although the bladder filling status has little effect on the radiation dose to the bladder,the volume change or the rate of volume change should be no more than 400 ml or 60％,respectively.Moderately filled bladder is recommended for positioning and treatment,which achieves satisfactory repeatability of the treatment.A volume change of more than 30 ml or a rate of volume change of higher than 30％ can result in an increase in the dose to the rectum.Empty rectum can effectively reduce the dose to the rectum.
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Objective To analyze the effect of image guidance on the doses to the rectum and bladder in radical external beam radiotherapy for cervical cancer, and to investigate the reasonable application mode of image-guided radiotherapy (IGRT) in the treatment of cervical cancer. Methods A total of 20 patients with cervical cancer who underwent helical tomotherapy(HT) in PLA Army General Hospital from 2012 to 2016 were enrolled in this study. A megavoltage computed tomography(MVCT) scan was performed before each treatment. The obtained MVCT images were used for dose reconstruction in the adaptive module of HT to obtain the actual dose (Plan-1) and the non-image-guided dose was simulated (Plan-2). Each single dose distribution and the corresponding fused CT image were sent to the software MIM 6.0 to obtain the total radiation dose by dose superposition. The radiation doses and volumes of the rectum and bladder were compared between the two therapeutic plans. Results The radiation doses to the rectum and bladder in Plan-2 were significantly higher than those in Plan-1. There were significant differences in Dmaxand V50of the rectum and V50of the bladder between Plan-1 and Plan-2(P=0.040;P=0.000;P=0.047). Compared with Plan-1, there were statistical differences in inter-fractional Dmaxand V50during the initial treatment (P=0.047,0.037), and V50of the rectum within the 13thto 21stradiotherapy, respectively (P=0.009, 0.017, 0.028). Besides, differences regarding Vmaxand V50in the initial treatment and the 21stto 23rdradiotherapy were close to the statistical significance when compared to those in Plan-1, respectively (P= 0.061,0.053; P= 0.072,0.058). Conclusions IGRT can reduce the radiation doses and volumes of the rectum and bladder, especially the rectum. The therapeutic plan should be rescheduled when tumor retraction is evident at half of the total radiation dose (around 13thfraction) in external beam radiotherapy. If it is difficult to achieve image guidance in each treatment,selective image guidance could be performed to effectively reduce the injuries of the rectum and bladder.
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Objective To determine the margins of planning target volume (MPTV) in primary cervical cancer patients with tomotherapy and evaluate the importance of automatic registration(AR) plus manual registration.Methods The setup errors of 29 primary cervical cancer patients receiving external radiation from June 2012 to Dec 2014 were measured by megavoltage computed tomography (MVCT),which were performed at least two times weekly before treatment and were registered with the planning CT.The setup errors between automatic registration and total shift (TS) including both AR and manual registration were compared MPTV was calculated.Results Setup errors were collecte from 443 sets of MVCT in 29 patients.AR and total shift (TS) values in the x,y,z directions and rotation angle were (-0.9±2.3),(0.0±3.1),(1.0±2.6) mm,0.2° ±0.8° and (-0.8±1.8),(-0.4±3.4),(l.4 ± 2.5) mm,0.1° ± 0.5°,respectively.There were statistically significant differences between the two groups in all directions except for the x axis (t =5.1,-5.2,3.2,P ＜ 0.05).MPTV were 4.6,5.7,3.3 mm in the x,y,z directions,respectively.Conclusions Manual registration is necessary after automatic registration in cervical cancer patients with tomotherapy.For patients with cervical cancer treated by tomotherapy,planning target volume MPTV parameters are suggested to be 5,6,4 mm in the x,y,z directions.
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Objective To use helical tomotherapy ( HT ) for determining the difference between actual doses and planning doses to the target volume and organs at risk ( OARs ) in patients with nasopharyngeal carcinoma receiving radiotherapy, and to provide guidance for the clinical treatment. Methods Localization and delineation of the target volume and OARs were performed by computed tomography ( CT) in 21 patients with nasopharyngeal carcinoma receiving radical radiotherapy using HT. All patients underwent megavoltage CT ( MVCT) scan prior to treatment. The obtained MVCT images were used for dose reconstruction in the adaptive module of HT, in which the actual dose was obtained and the non?image?guided dose was simulated. Each single dose distribution and the corresponding CT image were sent to software MIM6. 0 for superimposition, and the overall dose was obtained. The initial plan, image?guided plan, and non?image?guided plan were named Plan?1, 2, and 3, respectively. The dose distribution in the target volume and OARs was compared between the three plans with t ? test or wilcoxon test . Results Compared with those in Plan?1, the D98 values for the planning gross tumor volume ( PGTV) and planning target volume ( PTV) in Plan?2 were significantly reduced by 1. 16% and 2. 3%, respectively ( P=0. 025;P=0. 043);the volumes of the left and right parotids in Plan?2 were significantly reduced by 46. 0% and 46. 5% on average, respectively ( P=0. 000);the distances between the midline and the center?of?mass for left and right parotids were significantly reduced by 6. 9% and 6. 5%, respectively ( P=0. 000);the V26 and Dmean for both parotid glands were significantly elevated by 32. 8% and 25. 2%, respectively ( P=0. 000) . Compared with those in Plan?1, the D98 values for PGTV, PTV?1, and PTV?2 in Plan?3 were significantly reduced by 2. 0%, 1. 9%, and 2. 4%, respectively ( P=0. 001;P=0. 007;P=0. 036);the V26 and Dmean for both parotid glands in Plan?3 were significantly elevated by 33. 6% and 25. 3%, respectively ( P=0. 000);Dmax to the spinal cord was significantly increased by 6. 9%( P=0. 005) . There was no significant difference in D2 to the spinal cord between Plan?2 and Plan?1( P=0. 392) . Conclusions The doses to both parotid glands increase during HT for nasopharyngeal carcinoma, which is closely associated with the shift of the parotid glands toward the midline. Image?guided radiotherapy does not enhance the dose to the target volume, but reduces the dose to the spinal cord.
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Objective To observe the interfractional variation and actual dose for cervical cancer patients treated with tomotherapy.Methods Five patients who received tomotherapy were chosen from Aug 2013 to Feb 2014.A megavohage computed tomography (MVCT) scan was performed before treatment and then registered with the planning CT images.Dose distributions were recalculated and targets were contoured on the MVCT images.The differences between the actual radiation and planning were analyzed.Results In the patients received external radiotherapy, the decline in cervix volume and maximum diameter was 68.90％ and 26.91％ , respectively (t =5.21, 8.39, P ＜0.05).Cervix, uterus and CTV movement in left-right, anteroposterior, superoinferior were 1.43,-7.72, 0.02,-0.40,-1.24, -6.51,-0.43,-1.68and-0.22mm.The medianCTV V95％ was 99.40％ (95.96％-100％), and missing volume was 6.94 cm3 (0-32.30 cm3).Conclusions During radiotherapy for cervical cancer patients, the volume, position and doses are different between initial plan and actual radiation.Based on image guided radiation therapy (IGRT), missing targets are limited.
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Objective To analyze the response rate and prognostic factors for patients with locally recurrent rectal cancer treated with hypofractionated chemoradiotherapy without reresection.Methods Totally 52 patients with locally recurrent rectal cancer received hypofractionated irradiation and concurrent chemotherapy from January 2006 to January 2013 were enrolled.All patients received intensity-modulated radiotherapy (IMRT).The median dose was 63.4 Gy (61.6-64.4 Gy) at 2.2-2.3 Gy/f,5 f/week.Thirteen patients underwent prophylactic irradiation at lymph nodes region,the total dose of 45-50.4 Gy with conventional fraction and a simultaneous integrated boost was used.All patients received concurrent chemotherapy,capecitabine at 1 650 mg·m-2 ·d-1,divided into 2 times,5 d/week.The variables were compared by the chi-square test or Fisher's exact test.Local control (LC) and overall survival (OS) were calculated with using the Kaplan-Meier method.Results For all patients,the clinical complete response (CR),partial response (PR),stable disease (SD) and progressive disease (PD) was 23.1％,38.5％,32.7％ and 5.8％,respectively.The response rate (CR + PR) for patients with previous irradiation to pelvis and without were 37.1％ and 71.1％,respectively (x2 =5.40,P ＜ 0.05);for patients with 1 and 2 or more recurrent subsites were 81.8％ and 46.7％,respectively (x2 =6.63,P ＜ 0.05).Acute grade 3 skin and hematologic toxicities occurred in 19 patients (36.5％) and 1 patient (1.9％),respectively.None occurred grade 4 toxicity and none occurred grade 3 or more gastrointestinal and urologic toxicities.Four patients showed severe late toxicity of anastomotic stricture and performed a stoma at transverse colon.No other severe late toxicities were observed.The LC at 5 years was 49.1％ and the OS was 23.1％.Conclusions For patients with locally recurrent rectal cancer,hypofractionated chemoradiotherapy without resection is an acceptable and effective regimen,the response rate and long-term outcomes are promising.
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Objective To compare acute toxicity for stage Ⅱ-Ⅲ patients with rectal cancer irradiated with helical tomotherapy (HT) and conventional five-field intensity-modulated radiotherapy (5-IMRT).Methods The data of 84 stage Ⅱ-Ⅲ patients with rectal adenocarcinoma treated with concurrent chemoradiotherapy (CRT) were retrospectively analyzed.19 patients underwent postoperative CRT,and 65 patients underwent preoperative CRT.43 patients received radiotherapy with HT and 41 patients with 5-IMRT.The delineation on clinical target volume (CTV) and gross tumor target (GTV) was similar for two groups.The CTV to plan tumor volume (PTV) margins were 1.0 cm for patients with 5-1MRT and 0.5 cm for patients with HT.For all patients,a dose of 45.0-50.4 Gy,in daily fractions of 1.8 Gy,was delivered to PTV.For 45 patients with high risk factors,simultaneous integrated boost (SIB) was given to the tumor or tumor bed of a total dose of 55.0-60.0 Gy,in daily fractions of 2.1-2.3 Gy.Before treatment,the patients treated with HT underwent scanning by the tomotherapy-integrated megavoltage computed tomography (MVCT) scan modality and were positioned by co-registration of these images to the original kilovoltage planning CT image set.Concurrent capecitabine every day 1 600 mg/m2,twice daily on every day in the week.Results The rates of grade ≥ 2 acute cystitis were 7.0 ％ (3 cases) in HT group and 2.4 ％ (1 case) in 5-IMRT group (P =0.616),and ≥3 grade acute diarrhea were 4.7 ％ (2 cases) and 12.2 ％ (5 cases),respectively (P =0.259).≥2 grade leukopenia were 48.8 ％ (21 cases) and 19.5 ％ (8 cases),respectively (P =0.005),≥1 grade anemia were 34.9 ％ (15 cases) and 14.6 ％ (6 cases),respectively (P =0.032),and ≥1 grade thrombocytopenia were 23.3 ％ (10 cases) and 14.6 ％ (6 cases),respectively (P =0.314).Conclusions There is no significant difference in acute diarrhea and cystitis for patients treated with HT and 5-IMRT.Leukopenia and anemia in patients treated with HT are worse than those in patients with 5-IMRT,and thrombocytopenia is similar in the two groups.
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Objective To analyze the impact of parotid's position and volume changing on radiation dose for head and neck cancer treated with TomoTherapy.Methods Totally 12 patients with head and neck cancer were treated with TomoTherapy.Before the treatment,the dose distribution was recalculated with MVCT images,which would obtain the parameters of position,volume and actual radiation dose for parotids.Results The volume of parotids in Plan2 was significantly lower than in Plan1,and the percentage reduction was 29.06％ and 31.78％ for left and right parotid,respectively (Z =6.77,3.06,P ＜ 0.05).Distance between the COM (center of mass) of parotids and the midline of body was significantly smaller in Plan2 than in Plan1,and the percentage reduction was 6.72％ and 6.19％ (t =5.14,5.80,P ＜ 0.05) at left and right side,respectively.Average dose and V26 for both parotids were higher than those in Plan1,increasing by an average of 37.74％,25.08％ (Z =-6.03,-5.31,P ＜ 0.05) for left parotid and 30.45％,19.33％ (Z =-5.43,-3.26,P ＜0.05) for right parotid,respectively.Conclusions The actual radiation dose to parotids was significantly increased during the radiation therapy for patients with head and neck cancer.There was a linear correlation between the decrease of distance between the COM of parotids and the midline of body and the percentage increase of parotids' radiation dose.No correlation between the reduction of parotids' volume and dose to parotids.In order to reduce the parotids' radiation dose,modification of treatment plan at the appropriate time is essential.
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Objective To evaluate the effect of GTV volume on response of esophageal carcinoma.Methods From Jan.2004 to Dec.2008,72 cases newly diagnosed N0 stage thoracic esophageal carcinomas were included in this retrospective study.All treatment plans were set up and designed by CT simulator and 3D TPS.They received dose 56-70 Gy/27-33F/6-7w with 6MV X-ray.The GTV,the tumor length and maximum diameters were measured on the treatment planning system with the X-ray.RECIST standard was applied to evaluate the radiotherapy response of esophageal carcinoma.The effectiveness of related prognostic factors on survival was evaluated by univariate analyses.Results The short-term response with CR were 79％ with length ＜ 5 cm,48％ with 5-7 cm and 26％ with length ＞7 cm(P =0.003).The 1-,2-,3-and 5-year survival rates were 93％,79％,69％,69％ ; 91％,61％,46％,46％ and 80％,46％,28％,22％ (P =0.037).The short-term response with CR were 56％ with maximum diameters ≤3 cm and 33％ with maximum diameters ＞ 3 cm(P =0.033).The 1-,2-,3-and 5-year survival rates were 91％,72％,55％,37％ and 80％,45％,30％,30％ (P =0.037).The short-term response with CR were 52％ with GTV volume≤40 cm3 and 30％ with GTV volume ＞40 cm3(P =0.059).The 1-,2-,3-and 5-year survival rates were 91％,67％,51％,41％ and 80％,43％,27％,27％ (P =0.047).In the multivariate analysis,the length of GTV was likely to be the most important factor for the short-term response(P =0.005,0.014).Conclusions GTV volume,the tumor length and maximum diameters are factors for short-term response of N0 stage esophageal carcinoma.The GTV length is independent prognostic factor.The GTV length is the worse the prognosis will be.