Dosimetric study of five-field intensity-modulated radiotherapy compared with conventional three-dimensional conformal radiotherapy for rectal cancer

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.

Analysis of the efficacy and safety of conventional radiotherapy of chest wall and clavicular field and three-dimensional conformal radiotherapy in patients after modified radical mastectomy

Objective:To explore the efficacy and safety of conventional radiotherapy of chest wall and clavicular field and three-dimensional conformal radiotherapy in patients after modified radical mastectomy.Methods: A total of 84 patients who were admitted in our hospital after modified radical mastectomy were included in the study and divided into the conventional radiotherapy group (n=42) and the three-dimensional conformal radiotherapy group (n=42) according to different radiotherapy methods. The patients in the conventional radiotherapy group were given conventional radiotherapy of chest wall and clavicular field, while the patients in the three-dimensional conformal radiotherapy group were given three-dimensional conformal radiotherapy. The serum tumor markers and peripheral blood T lymphocyte subsets 6-8 weeks after treatment in the two groups were detected. The clinical efficacy, and toxic and side effects in the two groups were evaluated.Results: The serum CA15-3, CA125, CEA, and CK19 levels after treatment in the two groups were significantly reduced when compared with before treatment, CD3+,CD4+, and CD4+/CD8+ were significantly elevated, while CD8+ was significantly reduced when compared with before treatment, but the comparison of the above indicators between the two groups was not statistically significant. The occurrence rate of radioactive skin damage and pneumonia after treatment in the conventional radiotherapy group was significantly higher than that in the three-dimensional conformal radiotherapy group. Conclusions:The two kinds of radiotherapy schemes have an equal efficacy, but the toxic and side effects of three-dimensional conformal radiotherapy are significantly lower than those by the conventional radiotherapy, with a certain advantage.

Concurrent gemcitabine and cisplatin combined with 3D conformal radiotherapy for stage III non-small cell lung cancer

Objective： To study the toxicities and efficacy of concurrent gemcitabine plus cisplatin combined with three-dimensional conformal radiotherapy for stage Ⅲ non-small cell lung cancer （NSCLC）. Methods： Thirty-six patients with pathologically diagnosed NSCLC received radiotherapy and concurrent chemotherapy. There were 22 patients with stage Ilia and 14 patients with IIIb. Radiotherapy was given a total of 60-70 Gy in conventional fractionation. Chemotherapy included gemcitabine （600 mg/m^2） and cisplatin （20 mg/m^2）, once per week. Results： Thirty-two patients received a total dose of 60-72 Gy. Two patients received 56 Gy and another two patients received 58 Gy. Thirty-four patients received 4-6 weeks of chemotherapy, while two patients received only 2 weeks of chemotherapy. The overall response rate （CR ＋ PR）, complete response rate （CR）, partially response rate （PR） were 83.3% （30/36）, 11.1% （4/36） and 72.2% （26/36） respectively. The median follow-up duration was 18.4 months. The 1- and 2-year overall survival rates were 77.8% （28/36） and 55.6% （20/36）, respectively. Conclusion： Concurrent gemcitabine and cisplatin combined with three-dimensional conformal radiotherapy for stage III non-small cell lung cancer is effective and well tolerated. Lone-term results need further study.

Clinical observation in three-dimensional conformal radiotherapy (3D-CRT) with concurrent chemotherapy in treatment of postoperative cerebral gliomas

Objective:The aim of the study was to investigate the efficacy of three-dimensional conformal radiotherapy (3D-CRT) combined with Temozolomide (TMZ) concurrent chemotherapy in treatment of postoperative cerebral gliomas by prospective randomized controlled trials. Methods: Sixty-two patients with cerebral glioma who had residual tumor were divided into 3D-CRT group (radiotherapy group, n=31) and 3D-CRT with concurrent chemotherapy group (chemoradiotherapy group, n=31) prospectively. All patients received a dose of 50-60 Gy/25-30 F/5-6 weeks by 6 MV-X ray, three-dimensional conformal radiotherapy, 1 f/d, 5 times a week. Chemotherapy regimen was Temozolomide:75 mg/m2/d, concomitantly with radiotherapy, followed by 150-200 mg/m2/d, 5 days, 28 days per cycle, totally 3-6 cycles. Results: The total response rate was 35.3% (11/31) in radiotherapy group. The response rate was 61.3% (19/31) in chemoradiotherapy group. There was significant difference in curative effect (P=0.042). There was no significant difference in survival comparison of two groups (P=0.263). Stratified analysis showed the patients with grade Ⅲ gliomas of chemoradiotherapy group had better prognosis than ones of radiotherapy group (P=0.043). Conclusion: The 3D-CRT with concurrent chemotherapy can improve the survival of cerebral gliomas with pathological grade Ⅲ.

Clinical observation of three-dimensional conformal radiotherapy(3D-CRT) with concurrent chemotherapy in treatment of recurrent cervical cancers

Objective： The aim of the study was to explore the efficacy of three-dimensional conformal radiotherapy （3D- CRT） combined with TP concurrent chemotherapy in treatment of recurrent cervical cancers. Methods： From May 2005 to May 2009, 36 patients with recurrent cervical cancer were treated by 3D-CRT of 60-66 Gy and TP （docetaxel 70 mg/m^2, d1; cisplatin 20 mg/m^2, dl-d3; 21 days per cycle, totally 2 cycles） concurrent chemotherapy. Results： All of the patients had finished the 3D-CRT, the total response rate, complete response rate and partial response rate were 80.0% （28/35）, 45.7% （16/35）, and 34.3% （12/35）, respectively. The pain-alleviation rate was 91.4% （32/35）. The hemorrhage control rate was 94.3% （33/35）. The median overall survival was 21.2 months. The 1-, 2- and 3-year survival rates were 54.3%, 37.1% and 22.8%, respectively. The life qualities of the patients were improved, without any treatment related death. Conclusion： Radiotherapy is effective and well-tolerated for recurrent cervical cancers, and it can promote regional control of the disease and prolong survival time.

Curative 3D Conformal Radiotherapy of Non-Operated Prostate Adenocarcinoma at Pointe-a-Pitre University Hospital (Guadeloupe): About 29 Cases

Context: Technological advances have improved the toxicities of radiotherapy. We are evaluating the 3D technique in prostate cancer. Materials and Methods: Retrospective study from January 2015 to December 2015 with 29 files. Survival was calculated by Kaplan-Meier method. Results: We collected 29 patient records over the study period. The median age was 75 years with the following extremes: 54 years and 83 years. The median PSA level was 12 ng/ml with a range of 3.05 to 79 ng/ml. Gleason score analysis showed 6 patients (20.69%) with a score of 6 (3 + 3), 23 patients (79.31%) with a score of 7 including 12 patients (41.38%) with grade 3 and 11 patients (37.93%) with grade 4. The median dose delivered was 74 Gy, with a mean dose of 73.79 Gy and extremes of 70 Gy for the minimum and 76 Gy for the maximum. Hormone therapy was combined with radiotherapy in 17 patients (58.62%). Seven patients (24.14%) had grade 1 acute bladder toxicity and one patient (3.45%) had grade 2 acute toxicity. Late bladder toxicity was grade 1 in 5 patients (17.24%), grade 2 in 3 patients (10.34%) and grade 3 in 1 patient (3.45%). Late rectal toxicity, grade 2 in 3 patients (10.34%), grade 3 in 1 patient, was noted. Overall survival at 2 years was 100% and 89.65% at 5 years. Relapse-free survival at 2 years was 82.76% and 62.07% at 5 years. There were 3 deaths (10.34%) of which only one was related to prostate cancer. Conclusion: Radiotherapy, like surgery, is a fundamental option for the treatment of prostate cancers, particularly those that are locally advanced. It is gaining in importance with the improvement of techniques (IMRT, VMAT…) and new fractionations which contribute to the reduction of toxicities and the comfort of patients (shorter spread).

Clinical Research on Three-Dimensional Conformal Radiotherapy of Non-Small Cell Lung Cancer

OBJECTIVE To investigate the clinical efficacy and toxic effect of the 3-dimensional conformal radiation therapy （3DCRT） for non- small cell lung cancer （NSCLC）. METHODS Fifty-two patients with the Stage-I and IV NSCLC were treated with 3DCRT. Cross analysis of the clinical data was conducted in the comparison between the 52 cases with 3DCRT and the other 50 cases with the conventional radiation therapy （CRT）. In the 3DCRT group, only the primary tumor and positive lymph-node draining area were included in the clinical target area, setting 4 to 6 coplanar or non-coplanar irradiation fields, with 2 Gy or 3 Gy/fraction, 1 fraction a day and 5 fractions per week. The total dose ranged from a test dose （DT） of 66 Gy to 72 Gy. In the CRT group, the field area contained the primary tumor plus the homolateral hilum of the lung, the mediastinum superior or hol-mediastinum, and opposed anteroposterior irradiation. When the dosage reached DT 36-40 Gy, an oblique portal administered radiation was conducted in order to avoid injuring the spinal cord. The DT was 1.8-2.0 Gy/fraction, 1 fraction a day, 5 fractions per week, with a total dose of 60 Gy to 70 Gy. RESULTS The therapeutic effect （CR ＋ PR） was 90.4% in the 3DCRT group, and was 72% in the CRT group. There was statistically significant difference between the two groups, P 〈 0.01. There was a clinical symptom improvement attained by 96.5% and 86.4% respectively in the two groups, and there was a statistically significant difference between the groups, P 〈 0.01. The 6-month, 1 and 2-year overall survival rates were 92.3%, 75.0% and 42.3% in the 3DCRT group, and 76%, 60% and 30% in the CRT group, respectively. There was a significant difference in the 6-month overall survival rate between the groups, P 〈 0.05. There was no obvious significant difference in the 1 and 2-year overall survival rates between the two groups, P 〉 0.05. The toxic reaction was 12.5% and 23.7% respectively in the 3DCRT and CRT groups. Acute radioactive esophagitis and leucopenia were markedly lower in the 3DCRT group than in the CRT group. There was a statistically significant difference between the groups, P 〈 0.05. No toxic reaction of Stage-III and over was found in the 3DCRT group during radiation therapy. CONCLUSION The 3DCRT method has a satisfactory shortterm efficacy and improvement of clinical symptoms in treating NSCLC, with a mild toxic reaction and good tolerance in patients. It can be used for enhancing the tumor-control rate and bettering the quality of life.

Evaluation of whole-course three-dimensional conformal radiotherapy combined with late-course accelerated hyperfractionated radiotherapy for esophageal carcinoma patients

Objective： The aim of the study was to evaluate the therapeutic effect and safety of whole-course three-dimensional conformal radiotherapy （3DCRT） combined with late-course accelerated hyperfractionated radiotherapy （LCAFR） on patients with esophageal carcinoma. Methods： one hundred and one patients with esophageal carcinoma were divided into two groups. Observing group （49 cases） were treated by whole-course 3DCRT. Patients in control group （52 cases） were treated by conventional radiotherapy. Clinical efficiencies and radiation toxicities were compared between two groups. Results： The side effects including radiation esophagitis （63.2%） and tracheitis （49.0%） decreased in observing group, but there was no significant difference between two groups （69.2% and 55.7% in controls）. The 1-, 2-and 3-year tumor local control rates and overall survival rates in the observing group were significantly improved compared with the control group, being respectively 87.8%, 75.5%, 63.3% vs 71.2%, 55.8%, 42.3% and 85.7%, 71.4%, 46.7% vs 69.2%, 51.9%, 26.9% （all P 0.05）. Conclusion： The therapeutic effect of whole-course 3DCRT combined with LCAFR for esophageal carcinomas is superior to conventional radiotherapy.

Effects of three-dimensional conformal radiotherapy on the esophageal carcinoma

Objective： Radiation therapy is an important component of the multidisciplinary management of esophageal carcinoma. Three-dimensional conformal radiation therapy requires the precise definition of the target volume. We aimed to compare the treatment results and radiation toxicities between three-dimensional conformal radiotherapy （3D-CRT） and conventional radiotherapy （CR） for patients with cervical and thoracic esophageal carcinoma. Methods： From June 2004 to December 2006, a random study was performed on 106 patients treated with 3D-CRT or CR, 53 patients in each group. The patients in CR group received conventional radiotherapy in 2.0 Gy/f, 5 f/week and total dose was 66-70 Gy in 6.5 or 7 weeks. The patients in 3D-CRT group were treated by 3D-CRT in 2.0 Gy/f, 5 f/week and total dose was 64-70 Gy in 6 weeks. The local control rates, survival rates and radiation toxicities for the two groups were investigated. Results： The 1-year and 3-year local control rates were 83.0% and 60.4% in 3D-CRT group and 64.2% （x^2 = 4.853, P = 0.028） and 32.1% （x^2 = 9.812, P = 0.002） in CR group. The 1-year and 3-year survival rates were 73.6% and 50.9% in 3D-CRT group and 54.7% （x^2 = 4.102, P = 0.043） and 32.1% （x^2 = 3.886, P = 0.049） in CR group. Between the two groups, there was no significant difference in radiation toxicities. Conclusien： The 1-year and 3-year local control rates and survival rates of patients with esophageal carcinoma treated by 3D-CRT is superior to CR. However, longer-term results and radiation toxicity need further study which involves more patients and prolonged follow-up.

Three-Tesla Magnetic Resonance and Computed Tomography Imaging in Three-Dimensional Conformal Radiotherapy for Localized Prostate Cancer

Aims and background: we evaluate CT-3Tesla MRI fusion in conformal radiotherapy for localized prostate cancer.Methods: 18 consecutive patients underwent a 3T MRI scan under radiotherapy planning conditions, after the CT scan. Bowel and bladder preparation were prescribed. CT and MR images were automatically fused;prostate and seminal vesicles were contoured on CT and on MRI, organs at risk were defined on CT-MRI fusion. Late rectal and sexual toxicity, differences in target volume between MRI and CT and differences in rectal and penile bulb dose distribution based on CT only or on CT-MRI fusion were evaluated.Results: one patient experienced a late rectal toxicity;no patient had sexual toxicity. The difference between the mean MRI and CT target volumes was statistically significant (p = 0.0001 paired Student's t-test). The dose-volume histogram (DVH) analysis shows a significant reduction of the dose received by the rectum and the penile bulb in MRI-plans compared to CT-plans.Conclusions: 3 Tesla MRI scan under radiotherapy planning conditions along with bowel preparation significantly improves the definition of the target volume sparing normal tissue irradiation.

Management of Hepatocellular Carcinoma Patients with Portal Vein Thrombosis Using Three-Dimensional Conformal Radiotherapy

Objective: To determine the possible therapeutic gain of using three-dimensional conformal radiotherapy (3D-CRT) as a treatment option for portal vein tumor thrombus (PVTT) in patients with hepatocellular carcinoma (HCC) and to evaluate the tolerance and toxicity of using such treatment. Materials and methods: Sixty two patients were enrolled in this prospective study between June 2013 and August 2015. The clinical target volume (CTV) was the PVTT and the prescribed dose was 50 Gy/25 fractions. The median follow-up time was 7.4 months. Results: The thrombus crude response rate was 40.4% and the only significant prognostic factor for response was the thrombus size. Responders had significant better survival compared to non-responders with a median survival of 12.5 and 8 months respectively (P Conclusions: The results of this study suggest that radiotherapy should be considered as a safe treatment option for HCC patients with PVTT. It is effective not only for PVTT local control but also for survival, although prospective randomized trials are needed to confirm these results.

The follow-up of 34 children with medulloblastoma who received 3-dimensional conformal radiation therapy

Objective:In our investigation,we studied the patients with medulloblastoma who received 3-dimensional conformal radiation therapy(3DCRT) and recorded their effects,side effects and failure reasons.Methods:From August 2001 to August 2007,34 children with medulloblastoma were treated in our hospital.The age at diagnosis was 3-16 years old,and the mean age at diagnosis was 9.5 years old.Among all the patients,16 cases were included in the high risk group and 18 cases were included in the low risk group.All the patients were performed total resection or subtotal resection and no patients received radiotherapy or chemotherapy before operation.All patients received 3DCRT within 3 weeks after resection.The dose of 30 Gy were given to the whole brain and whole spine,followed by 20-25 Gy boosted to the posterior brain fossa.The median fraction dose was 180 cGy.Every patient received the chemotherapy scheme of the Lomustine,Cisplatinum and Vincristine.Nobody received intrathecal chemotherapy.The tests of the complete blood count,blood biochemistry,hepatic and renal functions were required before every cycle of chemotherapy.Results:5-year overall survival(OS) and 5-year disease free survival(DFS) were 71% and 62% respectively.The median follow-up time was 36.5 months.The 5-year OS of the high risk group was 71% compared to 62% of the low risk group.There were significant difference between the two groups(P = 0.01).There were 13 failure cases in all the patients.Of these 13 patients,10 were dead and the other 3 were alive with tumor.The complete remission(CR) rate was 70.5% and the partial remission(PR) rate was 14%.Among the failure patients,there were 3 patients(8.8%) with the recurrences located in the brain of cribriform region.The 5-year OS of the patients with preoperative metastases was 12.5%(1/8),and which of the patients with residual tumor volume > 1.5 cm3 was 0%(0/5).Through the statistic analysis,it was found that both whether or not the metastases were found before surgery and residual tumor volume have the significant impacts on the prognosis of the children with medulloblastoma(P < 0.05).The major adverse reactions were hematological toxicity(7/34,20.6%) and gastrointestinal reaction(4/34,11.8%).Conclusion:Through the using of 3DCRT for the children with medulloblastoma,the severe side effects rate was not high.The prognosis of the patients in low risk group was satisfied which was opposite to that of the patients in high risk group.And the patients with residual tumor volume > 1.5 cm3 and preoperative metastases also had poor prognosis.It is needed to pay attention to the possible low dose of the brain of cribriform region.

3D-CRT与IMRT两种放疗技术在原发性肝癌患者中的应用效果

目的:分析原发性肝癌患者实施三维适形放射治疗(3D-CRT)与强度调控放射治疗(IMRT)的效果。方法:回顾性分析2019年7月—2021年7月于漳州市医院收治的86例原发性肝癌患者的临床资料,根据治疗方法不同分为3D-CRT组(3D-CRT放射治疗)及IMRT组(IMRT放射治疗),各43例。比较两组剂量学参数、放疗照射时间、子野数、总子野跳数及危及器官受量;比较两组放疗后不良反应发生率。结果:IMRT组靶区平均剂量(PTVDmean)、靶区最小剂量(PTVDmin)、靶区最大剂量(PTVDmax)、靶区适形指数(CI)及靶区均匀指数(HI)均高于3D-CRT组,差异有统计学意义(P<0.05)。IMRT组的放疗照射时间长于3D-CRT组,子野数、总子野跳数少于3D-CRT组,差异有统计学意义(P<0.05)。IMRT组脊髓、左肾、右肾、胃受量低于3D-CRT组,差异有统计学意义(P<0.05)。IMRT组放疗后不良反应发生率低于3D-CRT组,差异有统计学意义(P<0.05)。结论:IMRT技术在原发性肝癌放射治疗中可有效提升靶区的照射剂量,并可降低放疗期间对危及器官的损伤程度。

非小细胞肺癌患者血清sTim-3和SPINK1水平与三维适形放疗效果及预后的关系

目的探讨非小细胞肺癌患者血清可溶性T细胞免疫球蛋白黏蛋白分子3(sTim-3)、丝氨酸蛋白酶抑制剂Kazal1型(SPINK1)水平与三维适形放疗效果及预后的关系。方法选取102例肺癌患者作为研究对象,收集患者的一般临床资料(包括年龄、性别、吸烟史、饮酒史、肿瘤直径、TNM分期、分化程度以及病理类型),抽取入院第2日空腹外周静脉血,采用酶联免疫吸附法(ELISA)检测血清sTim-3、SPINK1水平并据中位数大小将患者分为sTim-3低和高水平组、SPINK1低和高水平组;患者均进行三维适形放疗,随访12个月,观察并记录患者疗效,采用Kaplan-Meier生存曲线和log-rank检验研究血清sTim-3、SPINK1与患者预后的关系,采用COX回归研究非小细胞肺癌患者预后的影响因素。结果肿瘤直径>3.0 cm、肿瘤淋巴结转移(TNM)分期为Ⅲ~Ⅳ期、分化程度为低分化的非小细胞肺癌患者血清sTim-3、SPINK1表达水平高于肿瘤直径≤3.0 cm、TNM分期为Ⅰ~Ⅱ期、分化程度为中高分化的非小细胞肺癌患者(P<0.05);接受三维适形放疗后,血清sTim-3、SPINK1低水平组非小细胞肺癌患者总有效率高于高水平组(P<0.05);sTim-3、SPINK1高水平组非小细胞肺癌患者生存率分别低于对应的低水平组(P<0.05);sTim-3、SPINK1、TNM分期、分化程度是影响非小细胞肺癌患者预后的危险因素(P<0.05)。结论非小细胞肺癌患者血清sTim-3、SPINK1高表达与三维适形放疗疗效以及预后有关。

THREE-DIMENSIONAL CONFORMAL RADIATION THERAPY FOR LOCALLY RECURRENT NASOPHARYNGEAL CARCINOMA

Objective: To investigate the safety and effectiveness of three-dimensional conformal radiation therapy (3-D CRT) for locally recurrent nasopharyngeal carcinoma (NPC). Methods: From April 1998 to March 2000, 34 patients who had undergone previous external beam radiation therapy were retreated with 3-D CRT for locally recurrent NPC (33 poorly differentiated squamous cell carcinomas, 1 adenoma). The patients were re-staged according to Huaqing staging system with the following distribution: T1N0M0 in 5 cases, T2N0M0 in 11 cases, T3N0M0 in 12 cases, T4N0M0 in 6 cases. The maximal dimension of the gross tumor volume (GTV) ranged from 1.0 cm to 5.0 cm (median: 2.9 cm). CT simulation and 3-D planning were used to ensure full and conformal coverage of the planning target volume (PTV) by treated volume, while minimizing the absorbed dose of the adjacent normal tissue. 5–7 static conformal coplanar or noncoplanar portals were delivered for each fraction irradiation. The total dose delivered ranged from 65–70 Gy, with 2.5 Gy per fractionation, one fractionation per day, 5 days a week. Median follow-up time from 3-D CRT was 25 months (range: 12–36 months). Results: Over the follow-up period, local recurrence was observed in 3 patients, regional failure in 3, distant metastasis in 3, and six patients died; 88.2% (30/34) of the patient maintained local control, 82.4% (28/34) survived, and 76.5% (26/34) survived with no evidence of tumor. Acute complications were minor and few. The overall incidence of late complication was 20.6% (7/34), and severe complication was 14.7% (5/34), after re-irradiation with 3-D CRT. Conclusion: 3-D CRT is safety and effectiveness for most of the patients with locally recurrent NPC. Our preliminary results indicate a high local control rate and a low complication rate. The long-term curative effect and sequelae await further study.

Late course shrinking gross tumor volume (GTV) and boost radiotherapy for a special left lung cancer patient whose right lung was resected: a case report

We reported a special case of a locally advanced squamous cell carcinoma of the left lung. Due to pulmonary tuberculosis, the patient had underwent a complete right-side pulmonary lobectomy 20 years ago. Left lung supports his life, he is unable to carry on an operation treatment, so he accepted radiotherapy. Firstly, we defined gross tumor volume (GTV1) by CT simulation location, three-dimensional conformal radiotherapy (3D-CRT) was used until tumor dose reached 50 Gy/25 f. Secondly, by repeating the planning CT scan, defined GTV2, continued to radiotherapy by 2.5 Gy/f until the dose was 65 Gy/31 f. Using the same method for third CT scan, defined GTV3, continued to radiotherapy by 3 Gy/f until the total dose was 74 Gy/34 f. After radiotherapy, the patient acquired complete response and he had no obvious side-effect of radiotherapy. There has been no recurrence for 5 years now.

A dosimetric comparative study between conformal and intensity modulated radiation therapy in the treatment of primary nasopharyngeal carcinomas: the Egyptian experience

Objective: The study is a comparative study, the aim of which is to compare 3D conformal radiation therapy (3D-CRT) and intensity modulated radiation therapy (IMRT) in treating nasopharyngeal carcinomas; dosimetrically evaluating and comparing both techniques as regard target coverage and doses to organs at risk (OAR). Methods: Twenty patients with nasopharyngeal carcinoma were treated by 3D-CRT technique and another 20 patients were treated by IMRT. A dosimetric comparison was done by performing two plans for the same patient using Eclipse planning system (version 8.6). Results: IMRT had a better tumor coverage and conformity index compared to 3D-CRT plans (P value of 0.001 and 0.004), respectively. As for the dose homogeneity it was also better in the IMRT plans and the reason for this was attributed to the dose inhomogeneity at the photon/electron junction in the 3D-CRT plans (P value 0.032). Also, doses received by the risk structures, particularly parotids, was significantly less in the IMRT plans than those of 3D-CRT (P value 0.001). Conclusion: IMRT technique was clearly able to increase the dose delivery to the target volume, improve conformity and homogeneity index and spare the parotid glands in comparison to 3D-CRT technique.

Initial outcome of induction chemotherapy followed by radiotherapy and concurrent weekly paclitaxel for stage Ⅲ non-small cell lung cancer

Objective： The aim of our study was to evaluate the toxicity and efficacy of induction chemotherapy （ICT） followed by three-dimensional conformal radiotherapy （3D CRT） and concurrent weekly paclitaxel on unresectable non-small cell lung cancer （NSCLC）. Methods： Stage III NSCLC patients with favorable conditions were treated with 2 to 4 cycles of carboplatin （AUC = 5-6, dl） combined with paclitaxel （175 mg/m〈 dl）, then followed by weekly paclitaxel （40 mg/m2） and concurrent 3D CRT within 3-4 weeks. The prescription dose was given as high as possible under the condition that V20 〈 31% and spinal cord dose 〈 50 Gy. Results： Thirty-one patients were enrolled. ICT was well tolerated. During the concurrent chemoradiotherapy, the treatment of 3 patients was ended ahead of the schedule because of severe pulmonary and heart toxicities; the treatment of 2 patients was delayed for 7 and 12 days because of fatigue. Myelosuppression was mild （16/31）： all were grade 1-2 except 1 was grade 3. Lymphocytopenia was more obvious （29/31, grade 3 in 21）. Three patients developed grade 3 radiation-induced esophagitis, and 2 developed grades 3-4 radiation-induced pneumonitis. Two developed grade 3 esophageal stricture. No grades 3-4 pulmonary fibrosis was observed. The overall response rate was 74.1%. The 1-, 2-, 3-year overall survival rates were 74.2%, 41.9%, and 34.6%, respectively, with the median survival time of 18.5 months. The 1-, 2-, 3-year local progression-freely survival rates were 64.5%, 32.3%, and 20.5%, respectively, with the median local progression-freely survival time of 14.3 months. Conclusion： The program of ICT followed by weekly paclitaxel and 3D CRT is accomplished in most of the favorable stage III NSCLC patients. The toxicity is tolerable, and the response rate is inspiriting.

The impact of intensity modulated radiotherapy on the skin dose for deep seated tumors

Objective: The purpose of this study was to investigate the impact of intensity modulated radiotherapy (IMRT) on surface doses for brain, abdomen and pelvis deep located tumors treated with 6 MV photon and to evaluate the skin dose calculation accuracy of the XIO 4.04 treatment planning system. Methods: More investigations for the influences of IMRT on skin doses would increase its applications for many treatment sites. Measuring skin doses in real treatment situations would reduce the uncertainty of skin dose prediction. In this work a pediatric human phantom was covered by a layer of 1 mm bolus at three treatment sites and thermoluminescent dosimeter (TLD) chips were inserted into the bolus at each treatment site before CT scan. Two different treatment plans [three-dimensional conformal radiation therapy (3DCRT) and IMRT] for each treatment sites were performed on XIO 4.04 treatment planning system using superposition algorism. Results: The results showed that the surface doses for 3DCRT were higher than the surface doses in IMRT by 1.6%, 2.5% and 3.2% for brain, abdomen and pelvis sites respectively. There was good agreement between measured and calculated surface doses, where the calculated surface dose was 15.5% for brain tumor calculated with 3DCRT whereas the measured surface dose was 12.1%. For abdomen site the calculated surface dose for IMRT treatment plan was 16.5% whereas the measured surface dose was 12.6%. Conclusion: The skin dose in IMRT for deep seated tumors is lower than that in 3DCRT which is another advantage for the IMRT. The TLD readings showed that the difference between the calculated and measured point dose is negligible. The superposition calculation algorism of the XIO 4.04 treatment planning system modeled the superficial dose well.

Application of three dimensional conformal radiation therapy combined with high-intensity focused ultrasound for prostate cancer

Objective:Prostate cancer is a form of cancer that develops in the prostate,a gland in the male reproductive system.Prostate cancer tends to develop in men over the age of fifty;it is one of the most prevalent types of cancer in men.This article introduced a new method of prostate cancer treatment with the combination of three dimensional conformal radiation therapy (3D-CRT) and high-intensity focused ultrasound (HIFU),its efficacy was evaluated.Methods:From January 2004 to December 2009,95 patients were diagnosed with prostate cancer,among them,48 patients were received combined therapy with total irradiation of TD 60 Gy/30 Fx and 5 fractions of HIFU treatment,while 47 patients were received with pure 3D-CRT with total irradiation of TD (66-72) Gy/(33-36) Fx.Various indicators were evaluated,such as the local control rate and distant metastasis rate,the changes in blood PSA and fPSA,changes in T-lymphocyte subsets and NK cells,as well as acute adverse reaction of normal tissue.Results:The local response rate difference between the two groups had statistical significance (P < 0.05);the changes in blood PSA and fPSA were significant (P < 0.05);CD3+,CD4+,CD8+,CD4+/CD8+ and NK cells of the combined group increased obviously (P < 0.01),while the latter group had no increase (P > 0.05);the combined group had lower blood cells reduction and II-level acute adverse reaction of rectum,bladder and caput humeri than the pure group,but the II-level acute adverse reaction of urogenital canal in the combined group was higher (P < 0.05).Conclusion:The combined therapy with 3D-CRT and HIFU is a good way for the treatment of aged-related prostate cancer.It can ease the symptoms,control the disease and lengthen the survival time.