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Objective:To explore a new technique for lung dose reduction in esophageal cancer radiotherapy based on the dose distribution characteristics of the half-field combined with intensity-modulated radiotherapy (IMRT) technique.Methods:A three-dimensional water tank was used to measure the dose distribution at the edge of the symmetrical field and half-field, which was then compared and analyzed. Twenty patients with the middle and lower thoracic esophageal cancer receiving radiotherapy with prescription doses of 50.4-60.0 Gy were selected. Based on the Varian Vital beam linear accelerator and Eclipse planning system, flattening filter (FF) technique symmetrical field and half-field beam design and the flattening filter-free (FFF) technique symmetrical field and half-field design were adopted to compare and analyze various dose data and treatment MU numbers for the target area and the endangered organs. The field settings were chosen in the front 1 and back 4 mode.Results:Compared with the symmetrical field plan, the half-field plan significantly improved the irradiated dose to the lung with a statistically significant difference ( P<0.05), and the half-field FFF was slightly better than the half-field FF mode. Compared with the total lung V 5Gy, V 20Gy, V 30Gy, and D mean dosimetric parameters (Gy), the FF symmetric field and FFF half-field were (49.64±5.39)% vs.(42.70±5.53)%, (15.99±3.93)% vs.(13.32±3.06)%, (9.24±2.77)% vs.(8.50±2.62)%, and (10.45±1.76)% vs.(9.50±1.53)%, respectively. There was a significant reduction in the volume dose values for all structures of the lung (all P<0.05). For other comparative data, the irradiated dose for the heart of the symmetrical field was better than that of the half-field mode ( P<0.05), and the differences in conformity index (CI) and homogeneity index (HI), number of treated MU, and spinal cord associated with the target area were not statistically significant (all P>0.05). Conclusions:During radiotherapy for esophageal cancer, target area coverage and dose volume data of the lung are the main parameters affecting the efficacy and side effects. IMRT treatment based on the half-field mode can give full play to the advantages of half-field and IMRT, and significantly improve the irradiated dose to the lung, which can offer an additional clinical option.
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Objective:To propose an automatic planning method of intensity-modulated radiotherapy (IMRT) for esophageal cancer based on dose volume histogram prediction and beam angle optimization in Raystation treatment planning system.Methods:50 IMRT plans of esophageal cancer were selected as the training set to establish a dose prediction model for organs at risk. Another 20 testing plans were optimized in Raystation using RuiPlan and manual method, and the beam angle optimization and dose volume histogram prediction functions of RuiPlan were used for automatic planning. Dosimetric differences and planning efficiency between two methods were statistically compared with paired t-test. Results:There were no significant dosimetric differences in the conformity index (CI), homogeneity index (HI) of PTV, V 5Gy of both lungs and D max of the spinal cord between automatic and manual plans (all P>0.05). Compared with those in the manual plans, the V 20Gy and D mean of the left and right lungs generated from automatic plans were reduced by 1.1%, 0.37 Gy and 1.2%, 0.38 Gy (all P<0.05), and the V 30Gy, V 40Gy and D mean of the heart in automatic plans were significantly decreased by 5.1%, 3.0% and 1.41 Gy, respectively (all P<0.05). The labor time, computer working time, and monitor unit (MU) number of automatic plans were significantly decreased by 65.8%, 14.1%, and 17.2%, respectively (all P<0.05). Conclusion:RuiPlan automatic planning scripts can improve the efficiency of esophageal cancer planning by dose prediction and beam angle optimization, providing an alternative for esophageal cancer radiotherapy planning.
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In recent years, unconventional fractionated radiotherapy has shown increasing advantages in the treatment of multiple system tumors. Simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) involves the delivery of standard-fraction doses of radiotherapy to different areas, achieving the delivery of higher doses of radiotherapy per fraction to the high-risk gross tumor volume (GTV) without sacrificing the irradiation dose to the normal tissues. The dosimetric advantages of SIB-IMRT have been widely recognized. At present, the local control, survival advantage, indication population and the optimal upper limit of single fraction of SIB-IMRT for esophageal carcinoma are still unclear. This article reviews the application of SIB-IMRT in esophageal carcinoma.
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Objective:To investigate the relationship between Onodera′s prognostic nutritional index (PNI) and prognosis of patients with esophageal squamous cell carcinoma (ESCC) after definitive chemoradiotherapy or radiotherapy, aiming to provide a convenient, effective and accurate predictive indicator for evaluating the long-term survival of patients after treatment.Methods:Clinical data of 231 ESCC patients treated with definitive chemoradiotherapy or radiotherapy at the Fourth Hospital of Hebei Medical University from 2013 to 2015 were retrospectively analyzed. The PNI values of each patient at different radiotherapy periods were calculated and the ROC curve was used to determine the optimal cutoff value of PNI before radiotherapy, 231 patients were divided into the better-nourishment group ( n=86) and worse-nourishment group ( n=145). Kaplan- Meier method was used for survival analysis. Cox proportional hazards model was utilized to analyze the relationship between different nutritional status and prognosis. The short-term clinical efficacy and incidence of acute toxicities were statistically compared between two groups. Results:The mean values of PNI before, at week 3, week 6 and 1 month after radiotherapy were48.68±5.08, 39.68±4.87, 43.74±4.89 and48.31±4.92, respectively. The optimal cutoff value of pretreatment PNI was 49.25, the area under the curve (AUC) was 0.655, the sensitivity and specificity were 68.6% and 60.9%, respectively. The 5-year overall survival (OS) and progression-free survival (PFS) rates in the better-nourishment group (PNI≥49.25) were 36.0% and 31.3%, significantly better than 19.3% and 18.6% in the worse-nourishment group (PNI<49.25)( P=0.001, P=0.039). Multivariate analysis showed PNI before the therapy was an independent prognostic factor for OS ( P=0.021). Stratified analysis demonstrated that Stage Ⅰ/Ⅱ and concurrent chemotherapy patients in the better-nourishment group all obtained significantly better OS than their counterparts in the worse-nourishment group ( P=0.007, P=0.004). In addition, the objective response rate in the better-nourishment group was significantly higher than that in the worse-nourishment group ( P=0.047), whereas the incidence of ≥3 grade radiation esophagitis was lower than that in the worse-nourishment group ( P=0.060). Conclusions:Pretreatment PNI is a convenient and reliable indicator for predicting the long-term survival of ESCC patients after definitive chemoradiotherapy or radiotherapy. Patients with higher PNI have relatively better prognosis and radiotherapy tolerance, especially in those with early stage or concurrent chemotherapy.
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Objective@#To observe the variation trend of the peripheral blood lymphocyte-to-monocyte ratio (LMR) during radiotherapy in patients with esophageal cancer and analyze the relationship between LMR and the radiation-induced injury, aiming to provide parameters for accurate evaluation of radiotherapy responses and clinical efficacy.@*Methods@#Clinical data of 248 eligible patients undergoing definitive radiotherapy in our department from January 2013 to December 2015, 248 were retrospectively analyzed. The routine peripheral blood examination was performed weekly before, during and at the end of radiotherapy. The absolute number of lymphocyte and monocyte was recorded to calculate the LMR. The standard classification of LMR value was conducted based on the median value of each parameter. All data including the lesion length, lesion location, clinical stage and LMR were analyzed using the Kaplan-Meier, cox and logistic regression methods, respectively.@*Results@#LMR displayed an exponential decline during radiotherapy. Univariate analysis showed that the average LMR value was the influential factor of overall survival (P=0.011) and progression-free survival (P=0.017). The mean LMR value almost exerted significant effect upon local control rate (P=0.053). No significant correlation was observed between the mean LMR value and radioactive esophagitis and pneumonitis. Stratified analysis based on the results of multivariate analysis demonstrated that patients with higher average LMR value still had longer survival. Logistic regression model revealed that the length of esophageal lesion and irradiation pattern were the influential factors of the mean LMR value.@*Conclusions@#LMR value displays an exponential decline during radiotherapy. The greater amplitude prompts the worse prognosis. The wider the irradiation field and the greater decrease in LMR exert more obvious impact on the prognosis.
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Objective To observe the variation trend of the peripheral blood lymphocyte-tomonocyte ratio (LMR) during radiotherapy in patients with esophageal cancer and analyze the relationship between LMR and the radiation-induced injury,aiming to provide parameters for accurate evaluation of radiotherapy responses and clinical efficacy.Methods Clinical data of 248 eligible patients undergoing definitive radiotherapy in our department from January 2013 to December 2015,248 were retrospectively analyzed.The routine peripheral blood examination was performed weekly before,during and at the end of radiotherapy.The absolute number of lymphocyte and monocyte was recorded to calculate the LMR.The standard classification of LMR value was conducted based on the median value of each parameter.All data including the lesion length,lesion location,clinical stage and LMR were analyzed using the Kaplan-Meier,cox and logistic regression methods,respectively.Results LMR displayed an exponential decline during radiotherapy.Univariate analysis showed that the average LMR value was the influential factor of overall survival (P=0.011) and progression-free survival (P=0.017).The mean LMR value almost exerted significant effect upon local control rate (P=0.053).No significant correlation was observed between the mean LMR value and radioactive esophagitis and pneumonitis.Stratified analysis based on the results of multivariate analysis demonstrated that patients with higher average LMR value still had longer survival.Logistic regression model revealed that the length of esophageal lesion and irradiation pattern were the influential factors of the mean LMR value.Conclusions LMR value displays an exponential decline during radiotherapy.The greater amplitude prompts the worse prognosis.The wider the irradiation field and the greater decrease in LMR exert more obvious impact on the prognosis.
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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 clinical efficacy and analyze relevant prognostic factors of simultaneous integrated boost intensity-modulated radiation therapy ( SIB-IMRT ) for esophageal squamous cell carcinoma. Methods A total of 101 patients diagnosed with esophageal squamous cell carcinoma received SIB-IMRT from 2009 to 2015. The prescribed dose of PTV was 5040 cGy/28 times ( 180 cGy/time) and the dose for planning gross tumor volume (PGTV) was 6020 cGy/28 times (215 cGy/time) or 6160 cGy/28 times ( 220 cGy/time) simultaneously. The total treatment time was 5. 5 weeks ( once a day, 5 times a week).The adverse events, mode of treatment failure,l-,3-and 5-year local control (LC) and overall survival ( OS) rates were observed. Results The quantity of patients who completed the 1-,3-and 5-year follow-up was 101, 84 and 45, respectively. The 1-,3-and 5-year LC rates were 81. 6％,70. 4％ and 68. 4％, respectively. The 1-, 3-and 5-year OS rates were 72. 3％, 49. 4％ and 45. 2％, respectively. The median survival time was 36 months. Univariate and multivariate analyses showed that clinical staging ( stageⅠ/Ⅱ/Ⅲ) and tumor response ( complete remission/ partial remission/no remission ) were the prognostic factors of OS (P=0. 016,0. 000,0. 005,0. 000).There were no significant differences in the LC and OS between the two groups of 215 cGy and 220 cGy (P=0. 283,0. 951).The incidence rates of grade 1,2,3 acute pneumonitis were 10. 9％(11/101),2. 0％(2/101) and 2. 0％(2/101), respectively. The incidence rates of grade 1, 2, 3 acute esophagitis were 63. 4％( 64/101 ) , 10. 9％( 11/101 ) and 4. 0％( 4/101 ) , respectively. No acute esophageal perforation or hemorrhage occurred. Five patients experienced late pneumonitis ( two died) . One case developed late lemostenosis, two cases developed esophageal perforation and hemorrhage, and two patients experienced esophageal hemorrhage. The patients treated with a fractionated dose of 220 cGy had a higher incidence rate of acute pneumonitis and upper gastrointestinal adverse reactions than those receiving 215 cGy ( P= 0. 062, 0. 024 ) . The local failure and recurrence accounted for 62. 5％ of all treatment-related failures. Conclusions SIB-IMRT yields high long-term clinical efficacy and tolerable adverse events in the treatment of esophageal squamous cell carcinoma. Compared with the dose of 215 cGy, the fractionated dose of 220 cGy fails to improve LC and OS rates, whereas enhances the risk of adverse events. The clinical staging and short-term clinical efficacy are the prognostic factors of survival rate.