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Objective To evaluate the clinical efficacy of radical surgery combined with irradiation in the treatment of rectal cancer and its effect on the angiogenesis and survival rate.Methods A total of 200 colorectal cancer patients admitted to Zhengzhou Central Hospital from March,2014 to March,2015 were recruited and divided into the observation group (n=105) and control group (n=95) by using random number table method.In the control group,radical surgery was performed,and radical surgery combined with irradiation was conducted in the observation group.The clinical efficacy,the serum levels of vascular endothelial growth factor-C (VEGF-C) and prostaglandin E2(PGE2) were statistically compared between the control and observation groups.The changes of the microvascular morphology and microvessel density (MVD) in the rectal cancer tissues were observed and recorded.The 3-year survival rate was calculated during postoperative follow-up.Results After corresponding treatment,the clinical overall response rate was 86.67％ in the observation group,and 70.53％ in the control group (P＞0.05).The 2-year survival rate did not significantly differ between two groups (P＞0.05).The 3-year survival rate in the observation group was significantly higher than that in the control group (P＜0.05).After treatment,the serum levels of VEGF-C and PGE2 were significantly improved in two groups (both P＜0.05).In the observation group,the serum levels of VEGF-C and PGE2 were significantly lower compared with those in the control group (both P＜0.05).The microvessel morphology in the cancer tissues remarkably differed between two groups.The microvessel diameter did not significantly differ,whereas the lumen diameter in the observation group was significantly smaller than that in the control group.The MVD in the observation group was 12.25±3.35,significantly lower than 28.14± 17.26 in the control group (P＜0.05).Conclusion Radical surgery combined with irradiation is an efficacious treatment of rectal cancer,which can effectively improve the serum levels of VEGF-C and PGE2,decrease the MVD,reduce the lumen diameter in the cancer tissues,lower the angiogenesis in rectal cancer and enhance the survival rate,which deserves widespread application in clinical practice.
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Objective To evaluate the feasibility of keeping the consistency of bladder filing by a Bladderscan ( BS ) device during radiotherapy for rectal cancer. Methods The bladder volume was measured using a BS device and recorded. To verify the reliability of the BS measurement, the urinary output was determined by a measuring glass after complete urinary discharge. The bladder volume of 42 patients determined by the planning computed tomography ( CT) scans was used as the standard urinary volume. The bladder volume was measured using the BS device before radiotherapy every day. The chief complaint urinary volume was determined as the bladder volume when a patient felt a strong urge to urinate. The controlled urinary volume was determined as the urinary output intervened by the BS device to reach the standard urinary volume. Comparison was made by t test and data was assessed by Pearson correlation analysis. Results There was no significant difference in obtained urinary volume between the BS device and the planning CT scan ( P=0?84) . The urinary volume measured by the measuring glass was correlated with that measured by the BS device ( P=0?00 ) . The ability to hold urine in all patients was gradually weakened during treatment. The controlled urinary volume had a significantly smaller decrease after 1, 2, 3, 4, and 5 weeks of treatment than the chief complaint urinary volume ( 5% vs. 21%;6% vs. 20%;6% vs. 20%, 4% vs. 21%;11% vs. 26%;all P=0?00) . Conclusions Patients have a gradually decreased urinary volume during treatment. The intervention by the BS device gives a bladder volume close to that in the planning system, which results in a consistent bladder filling.
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Objective To investigate the influence of fixation of both lower limbs with negative pressure vacuum cushion and fixation of both ankles with self-made foam mat on setup errors in radiotherapy for rectal cancer.Methods A total of 12 patients with rectal cancer were enrolled in 2014 and randomly divided into group A (using negative pressure vacuum cushion) and group B (using self-made foam mat).An offline registration analysis was performed for the images of 108 times (A,B group of 54 times) of kilovoltage cone-beam CT (CBCT) before and after treatment.Grey scale translation error registration was used,and the results of registration were analyzed.The setup errors in x-axis (left-right direction),y-axis (cranial-caudal direction),and z-axis (anterior-posterior direction) were compared between the two groups.Results There was no significant difference in the absolute setup error in the y-axis between the two groups (2.13±0.64 mm vs.2.61±1.17 mm,P=0.399),while group A showed significantly lower absolute setup errors in the x-axis and z-axis than group B (x-axis:1.51±0.28 mm vs.2.70±1.05 mm,P=0.039;with an error rate of 7.41％ vs.42.59％;z-axis:1.10±0.29 mm vs.2.37±0.71 mm,P=0.002;with an error rate of 1.85％ vs.35.19％).Conclusions In the radiotherapy positioning for rectal cancer,fixation of both lower limbs with negative pressure vacuum cushion effectively avoids the translation and rotation of both lower limbs,reduces absolute setup errors,and has higher accuracy than fixation of both ankles with self-made foam mat.
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Objective To evaluate the dosimetric characteristics of helical tomotherapy (HT),intensity-modulated radiation therapy (IMRT) and three-dimensional conformal radiation therapy (3D-CRT) for postoperative radiotherapy of rectal cancer.Methods Ten male patients with stage Ⅱ or Ⅲ middle or low position rectal cancer were selected retrospectively.All of the 10 patients underwent Dixon surgery and CT simulation orientation.The target volumes and normal organs were drawn in the CT images and the plans for HT,IMRT and 3D-CRT were designed.The prescribed dose was given 50 Gy in 25 fractions,covering at least 95％ of the planning target volume.Results All plans met the needs of the prescribed doses.The HT and IMRT plans met the needs of dose limit to organs at risk,however,the 3D-CRT plans failed to do that.The conformity indexes of HT,IMRT and 3D-CRT plans were 0.86,0.82 and 0.62,respectively (F =206.81,P ＜ 0.001),and the homogeneity indexes were 0.001,0.157,and 0.205,respectively (x2 =15.8,P ＜ 0.001).The 3D-CRT plans had larger volumes than the HT plans and IMRT plans in the high-dose regions such as pelvic V50,bladder V40,bowel V50 and femoral head D5 (P ＜ 0.05),but the differences between the HT plans and IMRT plans were not statistically significant (P ＞0.05).The V15 value of bowel of HT plans were higher than those of the IMRT and 3D-CRT plans (71.1％ vs.63.3％ and 67.7％,respectively).However,there was no significantly difference.Conclusions All of the HT,IMRT and 3D-CRT plans are able to meet the prescription dose requirement of the target regions of rectal cancer.The HT plans show the best dose homogeneity and target conformity,followed by the IMRT plans,and then the 3D-CRT plans.The HT plans meet the needs of all OARs slightly better than the IMRT plans.3D-CRT plans are simple and practical with poor protective ability toward the OARs.
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ObjectiveTo evaluate the long-term survival and treatment failure patterns for patients with stage Ⅰ adenocarcinoma in the lower rectum after local excision with or without adjuvant radiotherapy.MethodsFrom Jan.2000 to Dec.2008,Seventy-seven patients with rectal cancer received local excision.Among them,41 received adjuvant radiotherapy.Fifty-four patients were pathologically proven as T1,the other 23 as T2.Patients were classified into low-and high-risk groups according to tumor grade,the length of tumor,surgical margin,circumference ratio of tumor/rectum and T stage.Survival rates and prognostic factors were estimated by Kaplan-Meier method,and comparisons were made by the Logrank test.Results Fourty patients were followed up more than 5 years.The 5-year locoregional recurrence-free survival (LRFS)and overall survival (OS)rates were 83％and 82％for the whole group.There were no significant differences in 5-year LRFS and OS rates in low-risk patients between local excision alone and local excision followed by adjuvant radiotherapy ( 86％ ∶ 83％,x2 =0.29,P =0.588 and 100％ ∶ 100％,x2 =1.50,P =0.221 ).In high-risk patients,the 5-year LRFS were similar (80％ ∶ 82％,x2 =0.27,P =0.600),but the OS were significantly different (92％∶ 66％,x2 =4.64,P =0.031 ) between local excision alone and local excision followed by adjuvant radiotherapy.By univariate analysis,large tumor size,positive margin,poor differentiation,tumor located less than 5 cm from anal verge and pT2 stage were poor prognostic factors for OS.The overall relapse rate for the whole group was 29％,and 70％ of them were locoregional relapse.The 5-year OS for patients treated with radical salvage surgery after local relapse was 69％.Conclusions For stage Ⅰ lower-sited rectal cancer,low-risk patients can achieve good result after local excision alone.The role of adjuvant radiotherapy in high-risk patients needs further evaluation.Local relapse is the main cause of failure,and salvage surgery after local relapse can provide long-term survival.
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ObjectiveTo explore the optimal method of protecting bone marrow in postoperative concurrent chemoradiotherapy of stage Ⅱ - Ⅲ rectal cancer by comparing two techniques of intensitymodulated radiotherapy (IMRT). MethodsFifteen patients with stage Ⅱ - Ⅲ rectal cancer after surgery had CT simulation. Clinical target volume, small bowel, bladder and bone marrow were contoured. Two IMRT treatment plannings with and without bone marrow-sparing (BMS-IMRT and IMRT) were separately designed. The dose distribution was compared based on that 95％ of the planning target volume received the prescribed dose. ResultsBMS-IMRT had an advantage over IMRT in terms of conformity indices ( 1. 06∶1. 04, t =- 2. 61, P =0. 023 ), but inferior to I M RT for homogeneity indices ( 0. 81 : 0. 75, t =- 2. 34, P =0.037)).Compared with IMRT, BMS-IMRT reduced the V5, V10, V20, V30, V40 of bone marrow (97.09％∶98.72％, t=-2.34, P=0.037;92.38％∶96.46％, t=-2.41, P=0.033;83.36％∶91.70％, t=-3. 18, P=0.008;51.47％∶69.65％, t=-4.92, P=0.000;36.34％∶49.57％, t=-2.66, P =0. 021 ). The doses received by small bowel and bladder were similar between BMS-IMRT and IMRT, except that the V20 of bladder was lower in BMS-IMRT (77. 32％∶92. 39％, t =-3.52, P=0. 004). Conclusions BMS-IMRT reduces low dose volume of bone marrow without increasing dose to other risk organs.BMS-IMRT might reduce acute hematologic toxicity and increase the feasibility of postoperative concurrent chemoradiotherapy in stage Ⅱ -Ⅲ rectal cancer.
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Objective To evaluate the feasibility and efficacy of chemoradiotherapy for locally advanced (inoperable) rectal cancer. Methods Seventy-six patients with locally advanced (T_4) or recurrent rectal cancer were randomized into two groups of concurrent chemoradiotherapy with either oxaliplatin plus 5-FU (oxaliplatin 130 mg/m~2, day 1,5-FU 350 mg/m~2, day 1 -5 ,LV 200 mg/m~2, day 1 -5, 4 weeks per cycle) or capecitabine (1650 mg/m~2, day 1 -14, 3 weeks per cycle) alone. All patients received pelvic three-dimensional conforrnal radiotherapy (3 DCRT) of 46 -50 Gy in 23 -25 fractions, with a boost of 14 -18 Gy in 7 -9 fractions. Results The median follow-up time was 19 months. The overall response rate was 64% in the oxaliplatin/5-FU group comparing with 58% in the capecitabine group (χ~2 = 0. 08 ,P =0. 772), with the median survival time of 22 months and 18 months (u = 17.71, P = 0. 077), respectively. The overall survival in the two groups was 68% and 63% at 1 year, and 21% and 19% at 2 years, respectively (χ~2 = 0. 97, P = 0. 326). There were no treatment-related deaths or grade 4 toxicities. Neutrocytopenia (39. 5% vs 77.7%, z = -3.97,P =0. 0001), diarrhea (47.4% vs 88.9%, z = -4. 78, P = 0. 0001), nausea and vomiting (68.4% vs 97.2%, z = -3. 17, P = 0. 0001), and neurotoxicity (5.3% vs 66.7%, z= -6.56, P= 0.0001) were more common in the oxaliplatin/5-FU group. Conclusions Concurrent chemoradiotherapy is well-tolerated and effective in patients with locally advanced (inoperable) rectal cancer.
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Objective To evaluate the dose distribution of target volume and normal tissues with different treatment planning such as three dimensional conformal radiotherapy(3DCRT) ,simplified intensity modulated radiotherapy(sIMRT) ,and intensity modulated radiotherapy (IMRT) for patients with radically resected rectal cancer. Methods Ten male patients with stage Ⅱ and Ⅲ rectal cancer after radical resection (Dixon surgery) were enrolled in this study. 3-field or 5-field 3DCRT,slMRT and 5-field or 7-field IMRT plans were performed for each patient. The dose distributions of target volume and normal tissues,conformal index(CI) and heterogeneous index(HI) were analyzed using the dose-volume histogram(Dvit). The prescription dose was 50 Gy in 25 fractions. Results The CI for PTV of IMRT and sIMRT was superior to 3DCRT. Conversely,the HI for PTV of 3DCRT was superior to sIMRT and IMRT. sIMRT and IMRT can protect the organs at risk better than 3DCRT. The mean of total MU for 3DCRT3f,3DCRT5f, sIMRT, IMRT5f and IMRTT7f was 482±13,504±11,455±42,841±36 and 884±46, respectively. Conclusions Comparing with 3DCRT plans and IMRT plans, sIMRT plan was the optimal plan for clinical practice. All of the three radiotherapy techniques can protect the rectal stump and anal canal well with the prescription dose of 50 Gy.
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Objective To evaluate the effect of radiotherapy(RT)combined with arterial infusion chemotherapy(AIC) in the treatment of locally advanced or recurrent rectal cancer. Methods From May.1994 to Dec.2000, 62 patients with locally advanced or recurrent rectal cancer were randomized into two groups: RT alone group(31 patients)and the combined group(RT+AIC, 31 patients). All patients were treated with conventional radiotherapy by 8 18 ?MV X ray to a total dose of D T40 50 ?Gy in 4 to 5 weeks for the resectable disease, or to a dose of 60 70 ?Gy in 6 to 7 weeks for the unresectable disease. However, the combined group received concurrent arterial infusion chemotherapy by DDP 70?mg/m 2 and 5 FU 600 ?mg/m 2 in 2 3 cycles. Results The response rates were 83.9% and 54.8% in combined group and RT alone group, respectively (P
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Objective To evaluate the effects of 3-dimensional conformal radiation therapy(3DCRT) in form of local control and survival of rectal cancer patients. Methods Forty-two patients with rectal cancer were irradiation by 3DCRT. They first received 40 Gy with larger field, at 1.8-2.0 Gy/f, 1 fraction qd, then followed by a boost of 24-27 Gy with reduced field, at 3.0-4.0 Gy/f, 1 fraction qod, to a total dose of 0,64-67 Gy. Results The 1-,2-,3-year survival rates were 83.3% ,64.3% and 45.2% .The 1-,2-,3-year local recurrence rates were 2.4%,11.9% and 23.9%. Conclusion Three-dimensional conformal radiotherapy is able to prolong the survival and improve the life quality of patients with rectal cancer.
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Objective To investigate the down stage effect and long-term results of preoperative chemoradiotherapy for locally advanced lower rectal adenocarcinoma. Methods From Jan. 1989 to Jul 1999, 103 patients suffering from lower rectal carcinoma were treated. Criteria entry: 1. Distance between anal verge and centre of tumor 4-8?cm(median 6.2?cm), 2. Uncertainty in decision of preservation of anus before admission, 3. Lesion belonged to locally advanced type, 4. definitive pathology, clinical stage and presence of objective observation of tumor extent, 5. Performance status proposed by Eastern Cooperative Oncology Group 0-2, 6. Age0.05), 25.5% and 48.5% (P
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0.05). ConclusionsConventional radiotherapy plus three dimensional conformal radiotherapy combined with chemotherapy may significantly improve the survival rate and reduce the distant metastasis rate of locally advanced or recurrent rectal cancer.