Late course three-dimensional conformal radiotherapy for esophageal carcinoma

Objective： The aim of our study was to evaluate the clinical results and acute side effects of late course three-dimensional conformal radiotherapy （3DCRT） for esophageal carcinoma. Methods： From January 2004 to October 2006, 70 patients with esophageal carcinoma received late course 3DCRT. Their clinical data were analyzed retrospectively. The short-term clinical results, acute side effects, local control rates and survival rates were evaluated. Results： The complete response rate was 62.9%, partial response rate was 35.7%, and the overall response rate was 98.6%. The 1-, 2-and 3-year local control rates were 77.1%, 51.4% and 45.7%, respectively. The 1-, 2-and 3-year overall survival rates were 75.7%, 54.3% and 38.6%, respectively. The median survival time was 26 months. Conclusion： The technique of late course 3DCRT is an effective treatment for esophageal carcinoma and tend to improve the overall survival rate.

Three-Dimensional Conformal Radiotherapy for Rectal Cancer and the Changes in Cancer Multi-biomarkers

OBJECTIVE To investigate the clinical efficacy of three-dimensional conformal radiotherapy （3D-CRT） for locally advanced or postoperatively relapsed rectal cancer, and to examine the changes in cancer multi-biomarkers. METHODS Sixty patients with locally advanced or postoperatively relapsed rectal cancer were randomly divided into two groups after 40 Gy external radiation, namely a late-course 3D-CRT group and a conventional radiotherapy group that served as the control. There were 30 patients in each group. For patients in the 3D-CRT group, multi-biomarkers were measured before and after radiotherapy and after relapse. RESULTS Response rates in the 3D-CRT and the control groups were 86.7% （26/30） and 70% （21/30） respectively, without a significant difference （P〉0.05）. The 1-, 2- and 3-year survival rates were 80%, 53.3% and 36.7% in the 3D-CRT group; in the control group the rates were 56.7%, 40% and 13.3% respectively, with a significant difference （P=0.0213）. CEA, CA19-9, CA242 and FER decreased after radiotherapy in the 3D-CRT group, P〈0.01, indicating a significant difference. The values after relapse were higher than those without relapse, P〈0.01, indicating a significant difference. CONCLUSION Conventional radiotherapy with a 3D-CRT boost gives better therapeutic effect to patients with locally advanced or postoperatively locally relapsed rectal cancer. A multi-biomarker protein chip diagnosis system can be utilized as an effective tool to determine the therapeutic effect and prognosis.

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.

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.

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.

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.

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.

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.

The clinical observation of three-dimensional conformal radiotherapy combined with FOLFOX chemotherapy for rectal cancer of postoperative local recurrence

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.

The effects of three-dimensional conformal radiotherapy combined with whole brain irradiation on brain metastases

Objective： To observe the recently therapeutic effects and toxicity of three-dimensional conformal radiotherapy combined with whole brain irradiation for patients with brain metastasis. Methods： 33 cases were treated by whole brain irradiation at first, the dose of which was 36-40 Gy （18-20 f）. Then three-dimensional conformal radiotherapy was added to the focus with a total dose of 20-25 Gy, whose fractionated dose was 2-5 Gy/time, 5 times/week or 3 times/week. Results： Within 1 month after radiotherapy, according to imaging of the brain, the CR of all patients was 45.5%, PR 36.4%, NC 15.1%, and PD 3%. For the 32 cases with neural symptoms before radiation, the CR of the symptoms was 40.6% and PR 59.4%. All patients gained different increases in KPS grade. By the end of the follow-up period, there were 22 deaths with the mean survival time up to 9.3 months. Conclusion： Three-dimensional conformal radiotherapy combined with whole brain irradiation can not only effectively control brain metastases and improve life quality, but also tends to prolong survival time.

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.

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.

Conformal Invariant Asymptotic Expansion Approach for Solving （3＋1）-Dimensional JM Equation

The （3＋1）-dimensional Jimbo-Miwa （JM） equation is solved approximately by using the conformal invariant asymptotic expansion approach presented by Ruan. By solving the new （3＋1）-dimensional integrable models, which are conformal invariant and possess Painlevé property, the approximate solutions are obtained for the JM equation, containing not only one-soliton solutions but also periodic solutions and multi-soliton solutions. Some approximate solutions happen to be exact and some approximate solutions can become exact by choosing relations between the parameters properly.

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.

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 conformal radiotherapy combined with transcatheter arterial chemoembolization for hepatocellular carcinoma

AIM: To compare transcatheter arterial chemoembolization (TACE) and 3D conformal radiotherapy (3D-CRT) with TACE monotherapy in hepatocellular carcinoma (HCC). METHODS: We searched all the eligible studies from the Cochrane Library, PubMed, Medline, Embase, and CNKI. The meta-analysis was performed to assess the survival benefit, tumor response, and the decline in alpha-fetoprotein (AFP) level. According to the heterogeneity of the studies, pooled OR with 95% CI were calculated using the fixed-effects or random-effects model. An observed OR > 1 indicated that the addition of 3D-CRT to TACE offered survival benefits to patients that could be considered statistically significant. Statistical analyses were performed using Review Manager Software. RESULTS: Ten studies met the criteria to perform a meta-analysis including 908 HCC participants, with 400 patients in the TACE/3D-CRT combination group and 508 in the TACE alone group. TACE combined with 3D-CRT significantly improved 1-, 2- and 3-year overall survival compared with TACE monotherapy (OR = 1.87, 95% CI: 1.37-2.55, P < 0.0001), (OR = 2.38, 95% CI: 1.78-3.17, P < 0.00001) and (OR = 2.97, 95% CI: 2.10-4.21, P < 0.00001). In addition, TACE plus 3DCRT was associated with a higher tumor response (complete remission and partial remission) (OR = 3.81; 95% CI: 2.70-5.37; P < 0.00001), and decline rates of AFP level (OR = 3.24, 95% CI: 2.09-5.02, P < 0.00001). CONCLUSION: This meta-analysis demonstrated that TACE combined with 3D-CRT was better than TACE monotherapy for patients with HCC, which needs to be confirmed by large multicenter trials. (C) 2014 Baishideng Publishing Group Inc. All rights reserved.

Stereotactic conformal radiotherapy of hepatic metastases:clinical analysis of 8 cases

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Dosimetric Comparison of Volumetric Modulated Arc Therapy (VMAT), 5F Intensity Modulated Radiotherapy (IMRT) and 3D Conformal Radiotherapy (3DCRT) in Rectal Carcinoma Receiving Neoadjuvant Chemoradiotherapy

Objective: To investigate better dosimetric distribution of volumetric modulated arc therapy (VMAT) vs. 5F intensity modulated radiotherapy (IMRT) and 3D conformal radiotherapy (3DCRT) in patients with locally advanced rectal cancer (LARC) when treated with neoadjuvant chemoradiotherapy. Methods: 3D-CRT, 5F-IMRT and VMAT plans for preoperative radiotherapy were 66011designed in 12 patients with locally advanced rectal cancer. The conformity index (CI) and homogeneity index (HI) in target volume, and the dose and volume of the organs at risk (OAR) irradiated including small bowel, bladder and bilatera1 femoral heads were compared among the three plans. Results: The CI for planning target volume (PTV) 2 and HI for PTV1 of VMRT and 5F-IMRT were superior to 3D-CRT. The CI of VMAT, 5F-IMRT and 3D-CRT plans were 0.71, 0.69 and 0.62 (p = 0.011 and p = 0.019, respectively). The HI of the VMAT and 5F-IMRT plans were both 1.04 and 3D-CRT planning was 1.06 (p = 0.022 and p = 0.006, respectively). The V35 - V45 of small bowel in VMAT were significantly less than in 5F-IMRT and 3D-CRT. V35 was 47.0, 56.4, and 72.8 cm3 for VMAT, 5F-IMRT, and 3D-CRT (p = 0.021 and p = 0.034, respectively), while V40 was 30.5, 35.5, 45.1 cm3 (p = 0.024 and p = 0.032, respectively) and V45 was 15.1, 18.1, 30.0 cm3 (p = 0.033 and p = 0.032, respectively). The D5, V30 and V50 of bladder in 3D-CRT were less than in VMAT and 5F-IMRT planning (p = 0.034, 0.004, 0.002 and p = 0.027, 0.003, 0.002, respectively). The Dmean of left femoral head in VMAT and 5F-IMRT were less than in 3D-CRT planning (p = 0.028 and p = 0.022, respectively) and the Dmean, V30 of right femoral head in VMAT and 5F-IMRT were better than in 3D-CRT planning (p = 0.044, 0.036 and p = 0.023, 0.028, respectively). Conclusions: Dosimetric analyses demonstrated that IMRT is superior to 3D-CRT in the conformity and homogeneity of dose distribution to the target volume, and provide a better protection to OARs sparing in patients with locally advanced rectal cancer for preoperative radiotherapy. With similar target coverage, VMRT is superior to 5F-IMRT in normal tissue sparing.

A study of transarterial infusion chemotherapy of gemcitabine plus three dimensional conformal radiotherapy for local advanced pancreatic cancer

Objective: To evaluate the clinical effect of transarterial infusion chemotherapy of gemcitabine plus three dimen- sional conformal radiotherapy on patients with local advanced pancreatic cancer. Methods: Fifty-one patients with local ad- vanced pancreatic cancer from June 2002 to February 2004 were enrolled, twenty-four patients of combined group were treat- ed with transarterial infusion chemotherapy of gemcitabine plus three dimensional conformal radiotherapy, while twenty-seven patients of control group were treated only with transarterial infusion chemotherapy of gemcitabine. Results: There were significant statistical differences between two groups in clinical benefit response (91.7% versus 74.1%, P < 0.01) and overall remission rate (70.8% versus 33.3%, P < 0.01). The 6-month survival rate, 12-month survival rate and 24-month survival rate of combined group were 83.3%, 62.5% and 37.5% respectively, while that of control group were 55.6%, 33.3% and 11.1% respectively. This showed significant difference between the two groups. Conclusion: Transarterial infusion chemotherapy of gemcitabine plus three dimensional conformal radiotherapy may be better than single transarterial infusion chemotherapy of gemcitabine in improving survival rates and elongating survival time of patients with local advanced pancreatic cancer.