Objective:Several studies have been conducted on the effects and toxicity of adding oxaliplatin to fluorouracilbased or capecitabine-based chemoradiotherapy(CRT)regimens as significantly increasing the toxic response ...Objective:Several studies have been conducted on the effects and toxicity of adding oxaliplatin to fluorouracilbased or capecitabine-based chemoradiotherapy(CRT)regimens as significantly increasing the toxic response without benefit to survival.In this study,we further explored the role of these two postoperative CRT regimens in patients with pathological stage N2 rectal cancer.Methods:This study was a subgroup analysis of a randomized clinical trial.A total of 180 patients with pathological stage N2 rectal cancer were eligible,85 received capecitabine with radiotherapy(RT),and 95 received capecitabine and oxaliplatin with RT.Patients in both groups received adjuvant chemotherapy[capecitabine and oxaliplatin(XELOX);or fluorouracil,leucovorin,and oxaliplatin(FOLFOX)]after CRT.Results:At a median follow-up of 59.2[interquartile range(IQR),34.0−96.8]months,the three-year diseasefree survival(DFS)was 53.3%and 64.9%in the control group and the experimental group,respectively[hazard ratio(HR),0.63;95%confidence interval(95%CI),0.41−0.98;P=0.04].There was no significant difference between the groups in overall survival(OS)(HR,0.62;95%CI,0.37−1.05;P=0.07),the incidence of locoregional recurrence(HR,0.62;95%CI,0.24−1.64;P=0.33),the incidence of distant metastasis(HR,0.67;95%CI,0.42−1.06;P=0.09)and grade 3−4 acute toxicities(P=0.78).For patients with survival longer than 3 years,the conditional overall survival(COS)was significantly better in the experimental group(HR,0.39;95%CI,0.16−0.96;P=0.03).Conclusions:Our results indicated that adding oxaliplatin to capecitabine-based postoperative CRT is safe and effective in patients with pathological stage N2 rectal cancer.展开更多
AIM: To investigate the effect of three-dimensional conformal radiotherapy (3-DCRT) in combination with FOLFOX4 chemotherapy for unresectable recurrent rectal cancer. METHODS: Forty-eight patients with unresectabl...AIM: To investigate the effect of three-dimensional conformal radiotherapy (3-DCRT) in combination with FOLFOX4 chemotherapy for unresectable recurrent rectal cancer. METHODS: Forty-eight patients with unresectable recurrent rectal cancer were randomized and treated by 3-DCRT or 3-DCRT combined with FOLFOX4 chemotherapy between September 2001 and October 2003. For the patients without prior radiation history, the initial radiation was given to the whole pelvis by traditional methods with tumor dose of 40 Gy, followed by 3-DCRT for the recurrent lesions to the median total cumulative tumor dose of 60 Gy (range 56-66 Gy); for the post-radiation recurrent patients, 3-DCRT was directly given for the recurrent lesions to the median tumor dose of 40 Gy (36-46 Gy). For patients in the study group, two cycles chemotherapy with FOLFOX4 regimen were given concurrently with radiotherapy, with the first cycle given simultaneously with the initiation of radiation and the second cycle given in the fifth week for patients receiving conventional pelvis radiation or given in the last week of 3-DCRT for patients receiving 3-DCRT directly. Another 2-4 cycles (average 3.6 cycles) sequential FOLFOX4 regimen chemotherapy were given to the patients in the study group, beginning at 2-3 wk after chemoradiation. The outcomes of symptoms relieve, tumor response, survival and toxicity were recorded and compared between the study group and the control group. RESULTS: For the study group and the control group, the pain-alleviation rates were 95.2% and 91.3%(P〉 0.05); the overall response rates were 56.5% and 40.0% (P〉0.05); the 1-year and 2-year survival rates were 86.9%, 50.2% and 80.0%, 23.9%, with median survival time of 25 mo and 16 mo (P〈 0.05); the 2-year distant metastasis rates were 39.1% and 56.0% (P= 0.054), respectively. The side effects, except peripheral neuropathy which was relatively severer in the study group, were similar in the the two groups and well tolerated. CONCLUSION: Three-dimensional conformal radiotherapy combined with FOLFOX4 chemotherapy for unresectable recurrent rectal cancer is a feasible and effective therapeutic approach, and can reduce distant metastasis rate and improve the survival rate.展开更多
AIM: To assess the usefulness of two independent histopathological classifications of rectal cancer regression following neo-adjuvant therapy. METHODS: Forty patients at the initial stage cT3NxM0 submitted to preope...AIM: To assess the usefulness of two independent histopathological classifications of rectal cancer regression following neo-adjuvant therapy. METHODS: Forty patients at the initial stage cT3NxM0 submitted to preoperative radiotherapy (42 Gy during 18 d) and then to radical surgical treatment. The relationship between "T-downstaging" versus regressive changes expressed by tumor regression grade (TRG 1-5) and Nasierowska-Guttmejer classification (NG 1-3) was studied as well as the relationship between TRG and NG versus local tumor stage ypT and lymph nodes status, ypN. RESULTS: Complete regression (ypT0, TRG 1) was found in one patient. "T-downstaging" was observed in 11 (27.5%) patients. There was a weak statistical significance of the relationship between "T-downstaging" and TRG staging and NG stage. Patients with ypT1 were diagnosed as TRG 2-3 while those with ypT3 as TRGS. No lymph node metastases were found in patients with TRG 1-2. None of the patients without lymph node metastases were diagnosed as TRG 5. Patients in the ypT1 stage were NG 1-2. No lymph node metastases were found in NG 1. There was a significant correlation between TRG and NG. CONCLUSION: Histopathological classifications may be useful in the monitoring of the effects of hyperfractionated preoperative radiotherapy in patients with rectal cancer at the stage of cT3NxM0. There is no unequivocal relationship between "Todownstaging" and TRG and NG. There is some concordance in the assessment of lymph node status with ypT, TRG and NG. TRG and NG are of limited value for the risk assessment of the lymph node involvement.展开更多
A clinical trial of radiotherapy with modified simultaneous integrated boost(SIB)technique against huge tumors was conducted.A 58-year-old male patient who had a huge pelvic tumor diagnosed as a rectal adenocarcinoma ...A clinical trial of radiotherapy with modified simultaneous integrated boost(SIB)technique against huge tumors was conducted.A 58-year-old male patient who had a huge pelvic tumor diagnosed as a rectal adenocarcinoma due to familial adenomatous polyposis was enrolled in this trial.The total dose of 77 Gy(equivalent dose in 2Gy/fraction)and 64.5 Gy was delivered to the center of the tumor and the surrounding area respectively,andapproximately 20%dose escalation was achieved with the modified SIB technique.The tumor with an initial maximum size of 15 cm disappeared 120 d after the start of the radiotherapy.Performance status of the patient improved from 4 to 0.Radiotherapy with modified SIB may be effective for patients with a huge tumor in terms of tumor shrinkage/disappearance,improvement of QOL,and prolongation of survival.展开更多
Objective:Prognosis of patients with locally advanced rectal cancer(LARC)but achieving yp T1–2N0 stage after neoadjuvant concurrent chemo-radiotherapy(CRT)has been shown to be favorable.This study aims to determ...Objective:Prognosis of patients with locally advanced rectal cancer(LARC)but achieving yp T1–2N0 stage after neoadjuvant concurrent chemo-radiotherapy(CRT)has been shown to be favorable.This study aims to determine whether the long-term outcome of yp T1–2N0 cases can be comparable to that of p T1–2N0 cohort that received definitive surgery for early disease.Method:From January 2008 to December 2013,449 consecutive patients with rectal cancer were treated and their outcome maintained in a database.Patients with LARC underwent total mesorectal excision(TME)surgery at4–8 weeks after completion of CRT,and those achieving stage yp I were identified as a group.As a comparison,stage p I group pertains to patients whose initially limited disease was not upstaged after TME surgery alone.After propensity score matching(PSM),comparisons of local regional control(LC),distant metastasis-free survival(DMFS),disease-free survival(DFS)and overall survival(OS)were performed using Kaplan-Meier analysis and log-rank test between yp I and p I groups.Down-staging depth score(DDS),a novel method of evaluating CRT response,was used for subset analysis.Results:Of the 449 patients,168 matched cases were generated for analysis.Five-year LC,DMFS,DFS and OS for stage p I vs.yp I groups were 96.7%vs.96.4%(P=0.796),92.7%vs.73.6%(P=0.025),91.2%vs.73.6%(P=0.080)and 93.1%vs.72.3%(P=0.040),respectively.In the DDS-favorable subset of the yp I group,LC,DMFS,DFS and OS resulted in no significant differences in comparison with the p I group(P=0.384,0.368,0.277 and0.458,respectively).Conclusions:LC was comparable in both groups;however,distant metastasis developed more frequently in down-staged LARC than de novo early stage cases,reflecting the need to improve the efficacy of systemic treatment despite excellent pathologic response.DDS can be an indicator to identify a subset of the yp I group whose longterm oncologic outcomes are as good as those of stage p I cohort.展开更多
Objective: The aim of the study was to compare the difference of dose distribution in clinical target volume and organ at risk (OAR) between five-field intensity-modulated radiotherapy (IMRT) and conventional thr...Objective: The aim of the study was to compare the difference of dose distribution in clinical target volume and organ at risk (OAR) between five-field intensity-modulated radiotherapy (IMRT) and conventional three-dimensional conformal radiotherapy (3DCRT) in the radiotherapy of rectal cancer. Methods: Fifteen patients with rectal cancer treated with radio- therapy (RT) were retrospectively analyzed. Among the patients, seven received RT preoperatively and 8 postoperatively. The target volume and the OARs such as the small bowel, bladder and femoral heads were contoured for each patient. 3DCRT-plan and IMRT-plan were performed for each patient respectively, with the prescribed dose covering at least 95% of the planning target volume (PTV). The conformity index (CI) and homogeneity index (HI) were used for evaluation of the dose distribution in the target volume, and the Dx% (the lowest dose to the x% volume of the OARs that received the highest dose of irradiation) and the mean dose were used for evaluation of the dose to OARs. Paired-T test was used for companson of the difference between the two plans. Results: In the IMRT-plan and 3DCRT-plan, the CI were 0.94 and 0.87 (P = 0.000) and the HI were 1.13 and 1.17, respectively (P = 0.001). For small bowel, the D30%, D50% and the mean dose were 19.67 Gy, 15.13 Gy and 18.81 Gy in the IMRT-plan and 25.20 Gy, 22.20 Gy and 22.89 Gy in the 3DCRT-plan, respectively (P 〈 0.001 for all pairs of parameters). For bladder, the D30%, D50%, and the mean dose were 24.80 Gy, 34.20 Gy and 28.70 Gy in the IMRT- plan, and 35.07 Gy, 44.67 Gy and 35.68 Gy in the 3DCRT-plan, respectively (P 〈 0.001 for all pairs of parameters). For femoral heads, the D5% in the IMRT-plan and 3DCRT-plan were 40.6 Gy and 40.47 Gy, respectively (P = 0.936), and the mean dose were 30.14 Gy and 25.57 Gy, respectively (P = 0.001). Conclusion: Five-field IMRT-plan is better than 3DCRT-plan in the conformity and the dose homogeneity within target volume and also better in sparing the small bowel and bladder.展开更多
Objective The aim of this study was to explore the three-dimensional conformal radiotherapy combined with FOLFOX scheme chemotherapy in the treatment of postoperative recurrence of rectal cancer.
BACKGROUND The management of rectal cancer patients is mainly based on the use of the magnetic resonance imaging(MRI)technique as a diagnostic tool for both staging and restaging.After treatment,to date,the evaluation...BACKGROUND The management of rectal cancer patients is mainly based on the use of the magnetic resonance imaging(MRI)technique as a diagnostic tool for both staging and restaging.After treatment,to date,the evaluation of complete response is based on the histopathology assessment by using different tumor regression grade(TRG)features(e.g.,Dworak or Mandard classifications).While from the radiological point of view,the main attention for the prediction of a complete response after chemotherapy treatment focuses on MRI and the potential role of diffusion-weighted images and perfusion imaging represented by dynamiccontrast enhanced MRI.The main aim is to find a reliable tool to predict tumor response in comparison to histopathologic findings.AIM To investigate the value of dynamic contrast-enhanced perfusion-MRI parameters in the evaluation of the healthy rectal wall and tumor response to chemo-radiation therapy in patients with local advanced rectal cancer with histopathologic correlation.METHODS Twenty-eight patients with biopsy-proven rectal adenocarcinoma who underwent a dynamic contrast-enhanced MR study performed on a 1.5 T MRI system(Achieva,Philips),before(MR1)and after chemoradiation therapy(MR2),were enrolled in this study.The protocol included T1 gadolinium enhanced THRIVE sequences acquired on axial planes.A dedicated workstation was used to generate color permeability maps.Region of interest was manually drawn on tumor tissue and normal rectal wall,hence the following parameters were calculated and statistically analyzed:Relative arterial enhancement(RAE),relative venous enhancement(RVE),relative late enhancement(RLE),maximum enhancement(ME),time to peak and area under the curve(AUC).Perfusion parameters were related to pathologic TRG(Mandard’s criteria;TRG1=complete regression,TRG5=no regression).RESULTS Ten tumors(36%)showed complete or subtotal regression(TRG1-2)at histology and classified as responders;18 tumors(64%)were classified as non-responders(TRG3-5).Perfusion MRI parameters were significantly higher in the tumor tissue than in the healthy tissue in MR1(P<0.05).At baseline(MR1),no significant difference in perfusion parameters was found between responders and nonresponders.After chemo-radiation therapy,at MR2,responders showed significantly(P<0.05)lower perfusion values[RAE(%)54±20;RVE(%)73±24;RLE(%):82±29;ME(%):904±429]compared to non-responders[RAE(%):129±45;RVE(%):154±39;RLE(%):164±35;ME(%):1714±427].Moreover,in responders group perfusion values decreased significantly at MR2[RAE(%):54±20;RVE(%):73±24;RLE(%):82±29;ME(%):904±429]compared to the corresponding perfusion values at MR1[RAE(%):115±21;RVE(%):119±21;RLE(%):111±74;ME(%):1060±325];(P<0.05).Concerning the time-intensity curves,the AUC at MR2 showed significant difference(P=0.03)between responders and non-responders[AUC(mm2×10-3)121±50 vs 258±86],with lower AUC values of the tumor tissue in responders compared to nonresponders.In non-responders,there were no significant differences between perfusion values at MR1 and MR2.CONCLUSION Dynamic contrast perfusion-MRI analysis represents a complementary diagnostic tool for identifying vascularity characteristics of tumor tissue in local advanced rectal cancer,useful in the assessment of treatment response.展开更多
Objective: Preservation of the pelvic autonomic nerves in order to lower bladder and sexual dysfunction after radical rectal cancer surgery & to evaluate functional outcome, local recurrence. Methods: A prospective...Objective: Preservation of the pelvic autonomic nerves in order to lower bladder and sexual dysfunction after radical rectal cancer surgery & to evaluate functional outcome, local recurrence. Methods: A prospective study was under- taken on Egyptian patients. Forty one patients participated in the study in the period from December 2002 till June 2004 where they underwent radical surgery but with preservation of the pelvic autonomic nerves this was followed by adjuvant pelvic radiotherapy. Results: Six months, 1-year and 2-year follow-up of urinary function was complete in 32 out of 41 (78%), 30 out of 41 (73%) and 27 out of 41 patients (65%) respectively There was no statistically significant correlation between the extent of nerve preservation and the reported minor voiding dysfunction. None of the patients reported major incontinence. Six months, 1-year and 2-year follow-up of sexual function revealed that 22 out of 41 patients (53%) were sexually active. Three out of 41 patients (7.3%) developed local recurrence. 38 (92.7%) patients were free of local recurrence, regarding pa- tients who received adjuvant radiotherapy 3 out of the 34 (8.8%) patients developed local pelvic recurrence while 9 patients (26.5%) developed distant metastases (3 of them did not receive adjuvant chemotherapy), while patients who received adju- vant chemotherapy, 2 out of 20 patients (10%) developed local recurrence while distant metastases developed in 6 patients (30%). Conclusion: Preservation of the pelvic autonomic nerves minimizes bladder and sexual dysfunction especially in male patients after rectal cancer surgery.展开更多
基金supported by grants from Sanming Project of Medicine in Shenzhen(No.SZSM202211030)the Science and Technology Department Basic Research Project of Shanxi(No.202203021221284)。
文摘Objective:Several studies have been conducted on the effects and toxicity of adding oxaliplatin to fluorouracilbased or capecitabine-based chemoradiotherapy(CRT)regimens as significantly increasing the toxic response without benefit to survival.In this study,we further explored the role of these two postoperative CRT regimens in patients with pathological stage N2 rectal cancer.Methods:This study was a subgroup analysis of a randomized clinical trial.A total of 180 patients with pathological stage N2 rectal cancer were eligible,85 received capecitabine with radiotherapy(RT),and 95 received capecitabine and oxaliplatin with RT.Patients in both groups received adjuvant chemotherapy[capecitabine and oxaliplatin(XELOX);or fluorouracil,leucovorin,and oxaliplatin(FOLFOX)]after CRT.Results:At a median follow-up of 59.2[interquartile range(IQR),34.0−96.8]months,the three-year diseasefree survival(DFS)was 53.3%and 64.9%in the control group and the experimental group,respectively[hazard ratio(HR),0.63;95%confidence interval(95%CI),0.41−0.98;P=0.04].There was no significant difference between the groups in overall survival(OS)(HR,0.62;95%CI,0.37−1.05;P=0.07),the incidence of locoregional recurrence(HR,0.62;95%CI,0.24−1.64;P=0.33),the incidence of distant metastasis(HR,0.67;95%CI,0.42−1.06;P=0.09)and grade 3−4 acute toxicities(P=0.78).For patients with survival longer than 3 years,the conditional overall survival(COS)was significantly better in the experimental group(HR,0.39;95%CI,0.16−0.96;P=0.03).Conclusions:Our results indicated that adding oxaliplatin to capecitabine-based postoperative CRT is safe and effective in patients with pathological stage N2 rectal cancer.
文摘AIM: To investigate the effect of three-dimensional conformal radiotherapy (3-DCRT) in combination with FOLFOX4 chemotherapy for unresectable recurrent rectal cancer. METHODS: Forty-eight patients with unresectable recurrent rectal cancer were randomized and treated by 3-DCRT or 3-DCRT combined with FOLFOX4 chemotherapy between September 2001 and October 2003. For the patients without prior radiation history, the initial radiation was given to the whole pelvis by traditional methods with tumor dose of 40 Gy, followed by 3-DCRT for the recurrent lesions to the median total cumulative tumor dose of 60 Gy (range 56-66 Gy); for the post-radiation recurrent patients, 3-DCRT was directly given for the recurrent lesions to the median tumor dose of 40 Gy (36-46 Gy). For patients in the study group, two cycles chemotherapy with FOLFOX4 regimen were given concurrently with radiotherapy, with the first cycle given simultaneously with the initiation of radiation and the second cycle given in the fifth week for patients receiving conventional pelvis radiation or given in the last week of 3-DCRT for patients receiving 3-DCRT directly. Another 2-4 cycles (average 3.6 cycles) sequential FOLFOX4 regimen chemotherapy were given to the patients in the study group, beginning at 2-3 wk after chemoradiation. The outcomes of symptoms relieve, tumor response, survival and toxicity were recorded and compared between the study group and the control group. RESULTS: For the study group and the control group, the pain-alleviation rates were 95.2% and 91.3%(P〉 0.05); the overall response rates were 56.5% and 40.0% (P〉0.05); the 1-year and 2-year survival rates were 86.9%, 50.2% and 80.0%, 23.9%, with median survival time of 25 mo and 16 mo (P〈 0.05); the 2-year distant metastasis rates were 39.1% and 56.0% (P= 0.054), respectively. The side effects, except peripheral neuropathy which was relatively severer in the study group, were similar in the the two groups and well tolerated. CONCLUSION: Three-dimensional conformal radiotherapy combined with FOLFOX4 chemotherapy for unresectable recurrent rectal cancer is a feasible and effective therapeutic approach, and can reduce distant metastasis rate and improve the survival rate.
文摘AIM: To assess the usefulness of two independent histopathological classifications of rectal cancer regression following neo-adjuvant therapy. METHODS: Forty patients at the initial stage cT3NxM0 submitted to preoperative radiotherapy (42 Gy during 18 d) and then to radical surgical treatment. The relationship between "T-downstaging" versus regressive changes expressed by tumor regression grade (TRG 1-5) and Nasierowska-Guttmejer classification (NG 1-3) was studied as well as the relationship between TRG and NG versus local tumor stage ypT and lymph nodes status, ypN. RESULTS: Complete regression (ypT0, TRG 1) was found in one patient. "T-downstaging" was observed in 11 (27.5%) patients. There was a weak statistical significance of the relationship between "T-downstaging" and TRG staging and NG stage. Patients with ypT1 were diagnosed as TRG 2-3 while those with ypT3 as TRGS. No lymph node metastases were found in patients with TRG 1-2. None of the patients without lymph node metastases were diagnosed as TRG 5. Patients in the ypT1 stage were NG 1-2. No lymph node metastases were found in NG 1. There was a significant correlation between TRG and NG. CONCLUSION: Histopathological classifications may be useful in the monitoring of the effects of hyperfractionated preoperative radiotherapy in patients with rectal cancer at the stage of cT3NxM0. There is no unequivocal relationship between "Todownstaging" and TRG and NG. There is some concordance in the assessment of lymph node status with ypT, TRG and NG. TRG and NG are of limited value for the risk assessment of the lymph node involvement.
文摘A clinical trial of radiotherapy with modified simultaneous integrated boost(SIB)technique against huge tumors was conducted.A 58-year-old male patient who had a huge pelvic tumor diagnosed as a rectal adenocarcinoma due to familial adenomatous polyposis was enrolled in this trial.The total dose of 77 Gy(equivalent dose in 2Gy/fraction)and 64.5 Gy was delivered to the center of the tumor and the surrounding area respectively,andapproximately 20%dose escalation was achieved with the modified SIB technique.The tumor with an initial maximum size of 15 cm disappeared 120 d after the start of the radiotherapy.Performance status of the patient improved from 4 to 0.Radiotherapy with modified SIB may be effective for patients with a huge tumor in terms of tumor shrinkage/disappearance,improvement of QOL,and prolongation of survival.
基金supported by Natural Science Foundation of China (No.81773241)Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences (No.2017I2M-1-006)
文摘Objective:Prognosis of patients with locally advanced rectal cancer(LARC)but achieving yp T1–2N0 stage after neoadjuvant concurrent chemo-radiotherapy(CRT)has been shown to be favorable.This study aims to determine whether the long-term outcome of yp T1–2N0 cases can be comparable to that of p T1–2N0 cohort that received definitive surgery for early disease.Method:From January 2008 to December 2013,449 consecutive patients with rectal cancer were treated and their outcome maintained in a database.Patients with LARC underwent total mesorectal excision(TME)surgery at4–8 weeks after completion of CRT,and those achieving stage yp I were identified as a group.As a comparison,stage p I group pertains to patients whose initially limited disease was not upstaged after TME surgery alone.After propensity score matching(PSM),comparisons of local regional control(LC),distant metastasis-free survival(DMFS),disease-free survival(DFS)and overall survival(OS)were performed using Kaplan-Meier analysis and log-rank test between yp I and p I groups.Down-staging depth score(DDS),a novel method of evaluating CRT response,was used for subset analysis.Results:Of the 449 patients,168 matched cases were generated for analysis.Five-year LC,DMFS,DFS and OS for stage p I vs.yp I groups were 96.7%vs.96.4%(P=0.796),92.7%vs.73.6%(P=0.025),91.2%vs.73.6%(P=0.080)and 93.1%vs.72.3%(P=0.040),respectively.In the DDS-favorable subset of the yp I group,LC,DMFS,DFS and OS resulted in no significant differences in comparison with the p I group(P=0.384,0.368,0.277 and0.458,respectively).Conclusions:LC was comparable in both groups;however,distant metastasis developed more frequently in down-staged LARC than de novo early stage cases,reflecting the need to improve the efficacy of systemic treatment despite excellent pathologic response.DDS can be an indicator to identify a subset of the yp I group whose longterm oncologic outcomes are as good as those of stage p I cohort.
文摘Objective: The aim of the study was to compare the difference of dose distribution in clinical target volume and organ at risk (OAR) between five-field intensity-modulated radiotherapy (IMRT) and conventional three-dimensional conformal radiotherapy (3DCRT) in the radiotherapy of rectal cancer. Methods: Fifteen patients with rectal cancer treated with radio- therapy (RT) were retrospectively analyzed. Among the patients, seven received RT preoperatively and 8 postoperatively. The target volume and the OARs such as the small bowel, bladder and femoral heads were contoured for each patient. 3DCRT-plan and IMRT-plan were performed for each patient respectively, with the prescribed dose covering at least 95% of the planning target volume (PTV). The conformity index (CI) and homogeneity index (HI) were used for evaluation of the dose distribution in the target volume, and the Dx% (the lowest dose to the x% volume of the OARs that received the highest dose of irradiation) and the mean dose were used for evaluation of the dose to OARs. Paired-T test was used for companson of the difference between the two plans. Results: In the IMRT-plan and 3DCRT-plan, the CI were 0.94 and 0.87 (P = 0.000) and the HI were 1.13 and 1.17, respectively (P = 0.001). For small bowel, the D30%, D50% and the mean dose were 19.67 Gy, 15.13 Gy and 18.81 Gy in the IMRT-plan and 25.20 Gy, 22.20 Gy and 22.89 Gy in the 3DCRT-plan, respectively (P 〈 0.001 for all pairs of parameters). For bladder, the D30%, D50%, and the mean dose were 24.80 Gy, 34.20 Gy and 28.70 Gy in the IMRT- plan, and 35.07 Gy, 44.67 Gy and 35.68 Gy in the 3DCRT-plan, respectively (P 〈 0.001 for all pairs of parameters). For femoral heads, the D5% in the IMRT-plan and 3DCRT-plan were 40.6 Gy and 40.47 Gy, respectively (P = 0.936), and the mean dose were 30.14 Gy and 25.57 Gy, respectively (P = 0.001). Conclusion: Five-field IMRT-plan is better than 3DCRT-plan in the conformity and the dose homogeneity within target volume and also better in sparing the small bowel and bladder.
文摘Objective The aim of this study was to explore the three-dimensional conformal radiotherapy combined with FOLFOX scheme chemotherapy in the treatment of postoperative recurrence of rectal cancer.
文摘BACKGROUND The management of rectal cancer patients is mainly based on the use of the magnetic resonance imaging(MRI)technique as a diagnostic tool for both staging and restaging.After treatment,to date,the evaluation of complete response is based on the histopathology assessment by using different tumor regression grade(TRG)features(e.g.,Dworak or Mandard classifications).While from the radiological point of view,the main attention for the prediction of a complete response after chemotherapy treatment focuses on MRI and the potential role of diffusion-weighted images and perfusion imaging represented by dynamiccontrast enhanced MRI.The main aim is to find a reliable tool to predict tumor response in comparison to histopathologic findings.AIM To investigate the value of dynamic contrast-enhanced perfusion-MRI parameters in the evaluation of the healthy rectal wall and tumor response to chemo-radiation therapy in patients with local advanced rectal cancer with histopathologic correlation.METHODS Twenty-eight patients with biopsy-proven rectal adenocarcinoma who underwent a dynamic contrast-enhanced MR study performed on a 1.5 T MRI system(Achieva,Philips),before(MR1)and after chemoradiation therapy(MR2),were enrolled in this study.The protocol included T1 gadolinium enhanced THRIVE sequences acquired on axial planes.A dedicated workstation was used to generate color permeability maps.Region of interest was manually drawn on tumor tissue and normal rectal wall,hence the following parameters were calculated and statistically analyzed:Relative arterial enhancement(RAE),relative venous enhancement(RVE),relative late enhancement(RLE),maximum enhancement(ME),time to peak and area under the curve(AUC).Perfusion parameters were related to pathologic TRG(Mandard’s criteria;TRG1=complete regression,TRG5=no regression).RESULTS Ten tumors(36%)showed complete or subtotal regression(TRG1-2)at histology and classified as responders;18 tumors(64%)were classified as non-responders(TRG3-5).Perfusion MRI parameters were significantly higher in the tumor tissue than in the healthy tissue in MR1(P<0.05).At baseline(MR1),no significant difference in perfusion parameters was found between responders and nonresponders.After chemo-radiation therapy,at MR2,responders showed significantly(P<0.05)lower perfusion values[RAE(%)54±20;RVE(%)73±24;RLE(%):82±29;ME(%):904±429]compared to non-responders[RAE(%):129±45;RVE(%):154±39;RLE(%):164±35;ME(%):1714±427].Moreover,in responders group perfusion values decreased significantly at MR2[RAE(%):54±20;RVE(%):73±24;RLE(%):82±29;ME(%):904±429]compared to the corresponding perfusion values at MR1[RAE(%):115±21;RVE(%):119±21;RLE(%):111±74;ME(%):1060±325];(P<0.05).Concerning the time-intensity curves,the AUC at MR2 showed significant difference(P=0.03)between responders and non-responders[AUC(mm2×10-3)121±50 vs 258±86],with lower AUC values of the tumor tissue in responders compared to nonresponders.In non-responders,there were no significant differences between perfusion values at MR1 and MR2.CONCLUSION Dynamic contrast perfusion-MRI analysis represents a complementary diagnostic tool for identifying vascularity characteristics of tumor tissue in local advanced rectal cancer,useful in the assessment of treatment response.
文摘Objective: Preservation of the pelvic autonomic nerves in order to lower bladder and sexual dysfunction after radical rectal cancer surgery & to evaluate functional outcome, local recurrence. Methods: A prospective study was under- taken on Egyptian patients. Forty one patients participated in the study in the period from December 2002 till June 2004 where they underwent radical surgery but with preservation of the pelvic autonomic nerves this was followed by adjuvant pelvic radiotherapy. Results: Six months, 1-year and 2-year follow-up of urinary function was complete in 32 out of 41 (78%), 30 out of 41 (73%) and 27 out of 41 patients (65%) respectively There was no statistically significant correlation between the extent of nerve preservation and the reported minor voiding dysfunction. None of the patients reported major incontinence. Six months, 1-year and 2-year follow-up of sexual function revealed that 22 out of 41 patients (53%) were sexually active. Three out of 41 patients (7.3%) developed local recurrence. 38 (92.7%) patients were free of local recurrence, regarding pa- tients who received adjuvant radiotherapy 3 out of the 34 (8.8%) patients developed local pelvic recurrence while 9 patients (26.5%) developed distant metastases (3 of them did not receive adjuvant chemotherapy), while patients who received adju- vant chemotherapy, 2 out of 20 patients (10%) developed local recurrence while distant metastases developed in 6 patients (30%). Conclusion: Preservation of the pelvic autonomic nerves minimizes bladder and sexual dysfunction especially in male patients after rectal cancer surgery.