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Objective:To analyze the data of ultra-high dose rate (FLASH) radiotherapy in GEO (Gene Expression Omnibus) database by bioinformatics method, in order to find the hub genes involved in flash radiotherapy induced acute T-lymphoblastic leukemia.Methods:The gene expression profiles of malignant tumors receiving FLASH radiotherapy were downloaded from GEO database. The R software was used to screen the differential expressed genes (DEGs) and analyze their biological functions and signal pathways. The protein-protein interaction (PPI) network of DEGs was analyzed by online tool of STRING, and Hub genes were screened by Cytoscape plug-in. The expressions of screened Hub genes in acute T lymphoblastic leukemia were identified with TCGA (The Cancer Genome Atlas) and GTEx (Genotype-Tissue Expression) database.Results:Based on the analysis of GSE100718 microarray dataset of GEO database, a total of 12 800 genes were found to be associated with radiosensitivity of acute T lymphoblastic leukemia, of which 61 significantly altered DEGs were selected for further analysis. It was found that these genes were involved in the biological processes of metabolism, stress response, and immune response through the pathways of oxidative phosphorylation, unfolded protein response, fatty acid metabolism, and so on. PPI analysis indicated that HSPA5 and SCD belonged to the Hub genes involved in the regulation of FLASH radiosensitivity, and they were significantly highly expressed in acute T lymphoblastic leukemia combined with TRD/LMO2-fusion gene.Conclusions:Through bioinformatics analysis, the Hub genes involved in regulating the sensitivity of FLASH radiotherapy and conventional radiotherapy can be effectively screened, and thus the gene expression profiles can be used to guide the stratification of cancer patients to achieve a precise radiotherapy.
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Objective:To analyze the adverse reactions, cosmetic effects and the improvement in positioning of breast cancer patients who received breast-conserving operation followed by hypofractionated radiotherapy and conventional radiotherapy based on the positioning of body membrane method with windowing method.Methods:From January 2019 to April 2020, 75 patients with breast cancer were randomly divided into two groups: hypofractionated radiotherapy (38 cases) administered with 42.4 Gy/16 fractions (2.65 Gy/fraction), and conventional group (37 cases) with 50 Gy/25 fractions (2.0 Gy/fraction). All of them were located by thermoplastic film, and the upper parts of the thermoplastic film were cut along the root of the breast. The adverse reactions, cosmetic effect and follow-up survival of the two groups were observed.Results:During the follow-up period, there was no recurrence in the two groups within 8 months. The local control rate and the survival rate of all the patients were both 100%. The total incidence of acute skin reaction in the two groups was 36.84% (14/38) in the hypofractionated group and 67.57% (25/37) in the conventional group ( χ2=7.09, P<0.05). The excellent and good rate of cosmetic effect was 89.47% (34/38) in the hypofractionated group and 78.38% (29/37) in the conventional group, but the difference was not statistically significant ( P>0.05). There were not statistically differences in the late skin reaction, leucopenia and thrombocytopenia between the two groups ( P>0.05). Conclusions:Breast-conserving surgery followed by hypofractionated radiotherapy with the positioning of body membrane windowing localization method is feasible and safe. Also, it can significantly reduce the acute radiation skin reactions. But the long-term effects still need to be confirmed by long-term follow-up.
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Introduction: With sectional imaging, wide variations are reported in pelvic anatomy of individual patients raising concerns over adequate coverage of target volume with conventional radiotherapy based on standard bony landmarks. Three-dimensional conformal radiotherapy (3DCRT) is reported to decrease normal tissue toxicity, along with decrease in chances of geographic miss. Present study is done for dosimetric comparison of Planning Target Volume (PTV) and Organs at Risk (OAR) in cancer cervix patients treated with conventional and conformal radiotherapy along with clinical correlation in terms of side effects and tumor response. Materials and Methods: Fifty patients of cancer cervix underwent planning contrast enhanced CT scan. Target volumes & OAR were contoured. Patients were randomized into conventional & conformal arms. Conventional fields were planned using standard bony landmarks. CT based radiotherapy planning was done for 3DCRT arm. Field sizes &dose volume histogram (DVH) were recorded & compared for target coverage & OAR sparing in both arms. All patients received concurrent chemotherapy followed by brachytherapy. Results: Field sizes used for the 3DCRT plans were significantly larger than those used for the conventional plans (p= 0.000). Optimal PTV coverage was significantly improved using 3DCRT as compared to conventional radiotherapy (p= 0.0001). Dose homogeneity in both arms were almost similar (p= 0.292), while conformity index was better in 3DCRT which was statistically significant between the groups (p= 0.000). Mean dose to the Planning Target Volume was increased significantly in the CT based plan when compared with the standard four field plan (p= 0.0001).Difference in doses to the organs at risk (urinary bladder, and small bowel)and their side effects were statistically significant across both groups. There was no difference in tumor response. Conclusion: The present study showed significantly better target volume coverage & dose homogeneity with 3DCRT which may translate into better local control & survival but longer follow up is required to validate it.
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Introduction: Lung cancer is the most common cancer worldwide and has a poor prognosis but integration of chemoradiationhas led to an increase in overall survival time and percentage of cured patients with acceptable toxicity.Purpose: The purpose of this study was to compare the efficacy of hyperfractionated (HFX) radiotherapy with conventionalradiotherapy and weekly concurrent paclitaxel in stage IIB/III non-small-cell lung cancer (NSCLC).Materials and Methods: A total of 60 patients were enrolled, of which 30 patients were given twice daily radiotherapy(1.2 Gy each) to a total of 72 Gy over 5–6 weeks and 30 patients were given single daily fraction (2 Gy) to a total of 66 Gy forthe same duration to achieve a comparable biological effective dose. Both groups received weekly 50 mg/m2 paclitaxel.Results: An overall response of 83.3% versus 56.6% with a partial response of 70% versus 53.3% and complete response(CR) of 13.3% versus 3% was seen in HFX radiotherapy versus conventional radiotherapy which was statistically significant(P = 0.04). 10 of 25 patients and 11 of 17 patients who achieved response in study and control groups, respectively, progressed.The median survival of patients in HFX radiotherapy arm was 18 months, compared to 9 months in conventional radiotherapyarm. The median time to local recurrence was 19 versus 11 months with local recurrence-free survival of 72% versus 66% at1 year follow-up. The 1 and 2 year survival rates were 76% and 40% in study arm and 50% and 26% in control arm (P - 0.005).Esophagitis (70% vs. 63.3%), skin reaction (70% vs. 63.3%), and radiation-induced pneumonitis (50% vs. 43.3%) were thecommon toxicities with no statistical significance between the two groups. Overall, there was mild chemotherapy-related toxicity.Conclusions: The combination of HFX radiation with weekly paclitaxel is effective treatment with a moderate degree of toxicityin stage IIB/III NSCLC. An average response to treatment and the use of lesser drugs have made us to consider this therapyin locally advanced NSCLC.
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Introduction: In India, almost 150,000 women are diagnosed with breast cancer every year and almost half of patients expected to die of the disease. In India most of patients with breast cancer diagnosed with advanced stage of the disease. As breast cancer treatment is multimodality approach Radiation therapy has significant impact on prevention of local recurrence. So, purpose of the study is to assess 5 year rates of local recurrence following post-operative 2D Radiotherapy treatment planning. Methods and Materials: We have selected 198 patients treated for post-operative 2D Radiotherapy treatment planning from September 2009-September 2010. All patients had undergone surgery in form of mastectomy or modified radical mastectomy. None of the patients with breast conservation surgery had been selected. All patients underwent chemotherapy either Induction chemotherapy following surgery or chemotherapy after surgery. All patients had been treated with 2D conventional Radiotherapy treatment plan with tangential fields and supraclavicular and axillary fields according to histopathology report. Patients were first taken on simulator machine and planning was done with breast wedge in position and fully abducted arm of the patient. Radiotherapy treatment dose was – 45Gy/20#, 2.25Gy/#, 5 days/week, total 4 weeks of treatment. Patients were assessed for acute toxicity every week. Patients were followed every monthly for 2 years, 2 monthly for 3rd year, 4 monthly for 4th year up to 5 year. Patients were assessed for Local recurrence up to 5 years. Results: 152 (77%) patients had undergone upfront Surgery. 46 (23%) patients were diagnosed with LABC, and had undergone chemotherapy first for downstage of the disease. After a median follow up of 34 months (range: 9-67 months), out of total 198 patients, 8.6% patients developed local recurrence. In which 6.5% (10 patients out of 152) in upfront surgery group and 15.2% (7 patients out of 46) in LABC group developed local recurrence. So, total 5% (10 patients) in upfront surgery group and 3.5% (7 patients) in LABC group out of 198 total patients developed local recurrence. Conclusion: Local recurrence after treatment of breast cancer with mastectomy+radiotherapy+/-systemic therapy is associated with a significantly higher risk of distant metastasis and death. So, in this retrospective study we have shown comparable results after 2D Conventional Radiotherapy Treatment Planning for prevention of local recurrence. Approach is safe, easy, and feasible, less time consuming and in Indian scenario where patients come in advanced stage of the disease and most of the time death is due to disease itself it is quite suitable approach at our centre. Also, we use hypofractionation regimen of 45Gy/20#, which is also feasible to reduce total treatment time and it has also shown equivalent results.
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Stereotactic body radiation therapy (SBRT) has been increasingly used in the treatment of early-stage non-small-cell lung cancer (NSCLC).Different from conventional radiotherapy,SBRT is characterized by the delivery of high-dose radiation in 1 to 5 fractions with a high degree of precision and steep dose gradients that minimize the dose to normal tissues,and image guidance technology,image fusion technology and respiratory gating system make the therapy more accurate.SBRT delivers higher biological equralent dose (BED) than conventional radiotherapy.The latest small sample data have suggested outcomes for SBRT patients that superior to the success rate of surgery,and the evidence for SBRT over conventional radiotherapy has resulted in a major change in the standard of care for inoperable NSCLC patients.
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Objective To observe the curative effect and adverse reactions of IMRT and conventional radiotherapy combined with chem-otherapy in treating patients with advanced nasopharyngeal carcinoma. Methods The patients were divided into the IMRT group (46 cases) and conventional radiotherapy combined with chemotherapy group ( 50 cases ) . Making the IMRT and conventional radiotherapy combined with chemotherapy treatment plan, and analyze the curative effect and adverse reaction of the two groups. Results Compared with the con-ventional radiotherapy combined with chemotherapy group, IMRT group has a significantly increase in complete remission rate and overall re-sponse rate, but there is no significant difference in long-term efficacy. The skin, dry mouth ( parotid) ,and oral mucositis response is lower in IMRT group, and the neutropenia incidence, prevalence of anemia, liver and kidney function damage rate is also significantly lower than conventional radiotherapy combined with chemotherapy. Conclusion The IMRT can significantly improve the curative effect in treatment of advanced nasopharyngeal carcinoma and reduce the adverse reactions compared with the conventional radiotherapy combined with chemotherapy.
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PURPOSE: Compared to conventional radiotherapy (RT), intensity-modulated radiotherapy (IMRT) significantly reduces the rate of treatment-induced late toxicities in head and neck cancer. However, a clear survival benefit of IMRT over conventional RT has not yet been shown. This study is among the first comparative study to compare the survival rates between conventional RT and helical tomotherapy in head and neck cancer. MATERIALS AND METHODS: From January 2008 to November 2011, 37 patients received conventional RT and 30 patients received helical tomotherapy for management of head and neck cancer. We retrospectively compared the survival rates between patients treated with conventional RT and helical tomotherapy, and analyzed the prognostic factors for survival. RESULTS: The 1- and 2-year locoregional recurrence-free survival rates were 61.2% and 58.1% for the conventional RT group, 89.3% and 80.3% for the helical tomotherapy group, respectively. The locoregional recurrence-free survival rates of the helical tomotherapy group were significantly higher than conventional RT group (p = 0.029). There were no significant differences in the overall and distant metastasis-free survival between the two groups. RT technique, tumor stage, and RT duration were significant prognostic factors for locoregional recurrence-free survival. CONCLUSION: This study showed the locoregional recurrence-free survival benefits of helical tomotherapy in the treatment of head and neck cancers.
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Humans , Head , Head and Neck Neoplasms , Neck , Radiotherapy, Intensity-Modulated , Retrospective Studies , Survival RateABSTRACT
Objective To compare the efficacy after conventional radiotherapy and late course accelerated fractionation radiotherapy for nasopharyngeal carcinoma (NPC).Methods A total of 200 NPC patients were enrolled and randomly assigned to conventional radiotherapy (CF) group with 99 cases or late course accelerated fractionation radiotherapy (LCAF) group with 101 cases,who received irradiation to 60Co γ or 6 MV X-rays.In the CF group,the total dose of nasopharynx was 70 Gy/35 fractions at 2 Gy daily.In the LCAF group,for the first two-thirds of the treatment,two daily fractions of 1.2 Gy were given to the primary lesion and the total dose was 48 Gy/40 fractions.For the last one third of the treatment,the dose per fraction was increased to 1.5 Gy and the total dose was 30 Gy/20 fractions.Results There were 25,16,25 in CF group and 16,13,18 patients in LCAF group who had recurrence of nasophaynx,cervical lymph nodes,and distant metastasis,respectively.The 5-year nasopharyngeal control and overall survival rates was 75.9％ and 87.6％ in CFgroup (x2 =4.066,P＜0.05),58.0％ and 74.1％(x2 =5.076,P ＜ 0.05) in LCAF group,respectively.Cervical lymph nodes local rates and distant metastasesfree rates at 5 years were 8 1.5％ and 90.0％ in CF group (P ＞ 0.05),74.1％ and 83.3％ (P ＞ 0.05) in LCAF group,respectively.Conclusions Compared with CF,LCAF can improve nasopharyngeal control and overall survival rates,but there are no significant difference in the recurrence rates of cervical lymph nodes and distant metastasis.
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Objective To retrospectively analyze the influence of intensity-modulated radiotherapy (IMRT) on tumor regression in primary nasopharyngeal carcinoma (NPC).Methods 272 patients with NPC received radical radiotherapy alone,196 by IMRT with a total treatment time of 6 weeks,and 76 by bilateral field conventional radiotherapy (CRT) with the total treatment timc of 7 weeks.Results By the end of radiotherapy,the primary tumor and neck lymph node residual rates of the IMRT group were 36.7％ and 44.2％,respectively,both significantly higher than those of the GRT group (21.1％ and 26.6％,x2 =6.15,3.99,P ＜ 0.05).Three months after the radiotherapy,residual lesions were observed at the nasopharynx or neck lymph nodes in 12 of the IMRT group,with a residual rate of 6.1％,not significantly different from that of the CRT group (9.2％,7/76).The 12 residual lesions of the IMRT group all vanished completely 4 -9 months after the radiotherapy.Conclusions There is an obvious difference in regressive mode between IMRT and CRT technique in NPC treatment.At the end of IMRT,the tumor residual rate is slightly increased.However,the delivered dose of gross tumor volume (GTV) is sufficient,and the boost dose should not be delivered indiscreetly.
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Objective To evaluate the dose distribution in clinical target volume (CTV) and organs-at-risk (OARs) in three dimension therapy plans in patients with squamous cell carcinoma of tongue receiving postoperative intensity-modulated radiotherapy (IMRT) or conventional radiotherapy (CRT) by dosimetric study. Methods Thirty-five patients with squamous cell carcinoma of tongue were divided into CRT group(n=17) and IMRT group(n=18). All patients underwent head-and-neck immobilization with a thermoplastic mask and planning CT scan, and target volume and OARs were contoured. Dose calculation and plan optimization were performed. All three dimension plans passed quality assurance before treatment. The dosimetry of therapy plans with IMRT or CRT in target volume and OARs dose distribution was compared by dose-volume histogram (DVH), conformity index (CI) and homogeneous index (HI). Results There were significant differences in D95 (isodose line to cover 95 percent target volume), CI, HI, minimum dose and maximum dose in CTV of therapy plans between patients with IMRT and CRT(P < 0.01), and there was no significant difference in mean dose of CTV(P > 0.05). The radiation dose on salivary glands (both parotid glands and contralateral submandibular gland) in patients with IMRT was significantly lower than that in patients with CRT(P < 0.01). Conclusion Compared with dose distribution of CRT plans, there are more advantages in improving dose distribution at the target volume and sparing salivary glands in IMRT therapy plans in patients with squamous cell carcinoma of tongue.
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Objective To analyze the dosimetfic benefits, clinical effect and side-respond of whole breast using intensity modulated radiotherapy for early breast cancer after conservative surgery. Methods From Oct.2004 to Aug. 2005,103 patients received the whole breast intensity modulated radiation therapy (IMRT). A dosimetric comparison of IMRT with conventional radiotherapy (CR) was performed on each patient. The cosmetic results, clinical effect and side-respond were observed. Results The average volume proportion of 95% and 107% prescribed dose was 95.8% ± 4.90% and 84.0% ± 20.7% (t = 9.60, P < 0.01) with IMRT and CR in clinical target volume, respectively. The V20 (lung volume of aceepted> 20 Gy/all lung volume × 100%) of the ipsilateral lung were 15.70% ± 4.64% and 23. 11% ± 7.88% (t = - 13.3, P < 0.01). The V30of the heart were 4.44% ±3.93% and 15.55% ± 10.89%(t = - 11.3, P< 0.01) with IMRT and CR respectively for sixty-three left side breast cancer patients. The 1- and 2-year excellent rate of good cosmetic outcome was both 100%. The 1-, 2- and 3-year local control rate was 99% ,99% and 98% ,respectively. The 1-, 2- and 3-year disease-free survival rate was 99% ,99% and 96% ,respectively. The Grade 1 and 2 acute radiation skin reaction rate was 95.1% and 4.9%, respectively. Conclusion Compared with conventional radiotherapy, IMRT improves dose distribution of CTV and reduce the dose of normal tissue around CTV;but with better clinical effects and lower side-respond for early breast cancer patients after breast conservative surgery.
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Objective To compare the dose distribution of mantle-field radiotherapy using conven-tional radiotherapy(CRT) and four intensity-modulated radiotherapy(IMRT) techniques in stage Ⅰ and Ⅱ Hodgkin's lymphoma(HL). Methods Ten patients with patholocally proved early stage HL underwent CT simulation. Then both CRT and IMRT planning performed using ECLIPS treatment planning system(TPS). The dosimetric parameters of different irradiation plans were analyzed, including conformal index (CI), homo-geneity index (HI), D95 and V95 of planning target volume (PTV), Dmax,Dmean,Dmin,V5,V10,V20 and V30 of the lung, as well as Dmax of the spinal cord. Results The isodose distribution and homogeneity of PTV were better in IMRT plans when compared with CRT plans. Target coverage, target dose conformity and homogene-ity were similar among all the four IMRT techniques. The V30 of the lung using IMRT was lower than using CRT,but the low-dose volume of the lung was higher. Among the four IMRT technique plans,the lung V20 and V30 were lower in plans with more-field technique,but the V5 and V10 were higher. The Dmax of the spinal cord using IMRT was all lower than that using CRT. Conclusions IMRT is better than CRT in target cov-erage, conformity, homogeneity and normal tissue sparing, especially in protecting the spinal cord and decrea-sing high-dose lung volume,though the low-dose lung volume is higher. Seven-field IMRT technique for man-de-field radiotherapy is recommanded.
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Objective To compare the dosimetric difference in planning target volume(PTV)and organ at risk(OAR)with conventional and the three-dimensional treatment planning for limlted-stage small cell lung cancer.Methods Ten patients with limited-stage small cell lung cancer were chosen in the present study.Two treatment planning were designed twice respectively with the Cadplan R 3.1.2 treatment planning system for each patient in two-course.The total radiation dose was 50 Gy.The dosimetric parameters were assessed with dose volume histograms in PIT and OAR.Results For the first course,the dose homogeneity indices(HI)of PTV1,conformal indices(CI)of PTV2,contralateral lung V3o and eontralateral mean lung dose in the three-dimensional treatment planning were better than that in the conventional treatment planning.For the second course,the HI,CI and mean dose of PTV1,CI and mean dose of PTV2 in the three-dimensional treatment planning were better than that in the conventional treatment planning.Conclusions By comparison with conventional treatment planning,the three-dimensional conformal treatment planning could meet the demands of dosimetrie requirements well for limited-stage small cell lung cancer with three-dimensional conformal radiotherapy,but with no significant dnsimetric differences in the OAR.
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Objective To assess the feasibility of applying intensity-modulated radiotherapy(IMRT)simultaneous integrated boost(SIB)to replace conventional radiotherapy(CR)plus brachytherapy of whole pelvis in locally advanced cervical eaneer(LACC).Methods Five LACC patients based difference position of uterus were chosen and worked out CR and IMRT SIB plans respectively.Dose distributions were compared between IMRT SIB and CR.Results When uterus was in ante-,neutral-,retro-pnsition and deviation respectively,IMRT SIB could provide enough and homogeneous dose distribution for target volume and reduce irradiated volumes and doses for organs at risk(recta,bladder and small intestine)than CR.The doses of the A,B,and fundus of uterus were higher in IMRT SIB than CR.However,in ease of small intestine was close to or encircled the uterus,the targets volume dose would be inadequacy.Conclusions LACC IMRT SIB's dose distribution is better than CR(except excess ante-position)and may help to treat those patients who couldn't be suitable with brachytherapy.
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Objective To analyze the treatment results of primary nasopharyngeal carcinoma(NPC)treated by four different external beam radiation therapy(EBRT)techniques in Sun Yat-sen University Cancer Center in the beginning of the 21 st century.Methods The data of 1093 hospitalized primary NPC patients treated in Sun Yat-sen University Cancer Center between December 2001 and June 2003 were retrospectively analyzed.The stage distribution(by AJCC/UICC,2002)was 63,439,358 and 233 patients in Stage Ⅰ,Ⅱ,Ⅲ and Ⅳa+Ⅳb.Definitive radiotherapy was given to all patients and the median total dose was 70 Gy.Four different EBRT techniques were used:812 patients with fluoroscopy simulation conventional radiotherapy(CR),155 patients with CT simulation conventional radiotherapy(CT-sim CR),69 patients with three dimensional conformal radiotherapy(3DCRT)and 57 patients with intensity modulated radiotherapv(IMRT). Results The 5-year local failure-free rate(LFFR),nodal failure-free rate(NFFR),and distant metastasis-free rate(DMFR)were 86.8%,95.3%and 83.2%,respectively.The 5-year progressionfree survival(PFS)and overall survival(OS)were 66.9%and 77.9%,respectively.Different EBRT techniques influeneed the OS and the LFFR of patients,the 5-year OS and LFFR of group CR,CT-sim CR,3DCRT and IMRT were 75.9%,83.5%,87.2%,86.6% and 84.5%,96.4%,91.0%,91.7%,respectively(P=0.014 and 0.006).The morbidity and severity of xerostomia and trismus were sigficantly lower in group 3DCRT and IMRT than in group CR and CT-sim CR(P=0.000 and=0.023). Conclusion The CT simulation technique,3DCRT and IMRT can improve the OS,LFFR and life qualitv of patients with primary NPC.
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Objective To evaluate the long-term efficaey of radiotherapy (RT) alone for nasopharyngnal eareinoma(NPC). Methods 934 NPC patients initially treated by conventional RT alone in 1999 were reviewed retrespeetively, including 676 males and 258 females. According to 92' Fuzhou staging system,there were 35 stage Ⅰ,215 stage Ⅱ ,488 stage Ⅲ and 196 stage Ⅳ diseases. All patients were treated by conventional RT alone with two opposing parallel faeio-eervical fields. The total dose delivered to the nasopharynx was 66-88 Gy. The dose to the cervical lymph nodes was 60-70 Gy, while the prophylactic dose to the neck was 50-56 Gy. Results The median follow-up was 67.1 months. The 5- and 8-year overall survival(OS), disease-free sutural, relapse-free survival and metastasis-free survival rates were 68.30%, 67.3% ,64.4% ,72.4% ,and 48.0% ,66.6% ,50.8% ,68.0% (χ2=49.74, P=0.000), respectively. For stage N1patients,the 5-and 8-year overall survival(OS) ,disease-free survival ,relapse-free survival and metastasis-free survival rates were significantly lower than those of stage NO patients [66.0% : 77.4% and 50.3%:59.8%(χ2=33.34,P=0.000);66.8%:76.1% and 66.1%:76.1%(χ2=29.08,P=0.000); 63.4%:72.9% and 48.9% : 58.7% (χ227.65,P=0.000);71.0%:80.8% and 63.4%:68.0%(χ2=26.13,P=0.000)]. And the corresponding rates of stage N<1-2>were significantly higher than stage N3,while no statistical difference was observed between stage N1 and N2. Multivariate analysis showed that sex, age, pathology,T stage and N stage were independent prognisitie factors for OS. Conclusions Radical RT alone could obtain good long-term results in early stage NPC. Tlowever,OS for local-regionally advanced stage NPC was still unsatisfactory because of the high relapse and metastatic rate. Clinical stage and N stage were valuable prognostic factors.
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Background and purpose:Coventional radiation has been used for decades,but the 3D dose distribution has not been studied as yet.In this study,different treatment plans of conventional irradiation technique for esophageal carcinoma have been evaluated by 3-D TPS.Methods:Five patients with esophageal carcinoma at upper-thoracic and five patients at middle-thoracic were enrolled in this study.Three conventional treatment plans were created for each patient,with a prescribed dose of 70 Gy.For tumor at upper-thoracic,plan 1 consisted of one anterior field and bilateral posterior oblique fields with wedges,plan 2 consisted of anterior bilateral oblique fields with wedges ,plan 3 consisted of a pair of AP-PA portals,then followed by right anterior oblique portals and left posterior oblique portals to spare spine cord.For tumor at middle thoracic,plan 1 consisted of one anterior field and bilateral posterior oblique fields.Plan 2 consisted of a pair of AP-PA portals and followed by another pair of parallel-opposed lateral off- cord fields as boost.Plan 3 used the same plan as for the lesion at upper-thoracic.The evaluation of each treatment plan was carried out by dose-volume histogram(DVH).Results:For tumor at upper-thoracic,on average,the maximum dose to spinal-cord in plan 3 was (57.1?4.9)Gy,and was higher than that in plan 1 and plan 2.Plan 1 increased mean lung dose from (12.8?2.1)Gy to (18.2?4.1)Gy(P=0.045)compared with plan 2,but it improved the homogenous dose of PTV2,especially in the patient with long tumor.For tumor at middle-thoracic,on average,plan 2 increased mean lung dose from (11.9?1.1)Gy to (13.0?0.6)Gy(P=0.045) compared with plan 3.Plan 2 increased V_(20) and V_(30) from (23.6?2.3)% to (29.2?1.9)%(P=0.004) and (13.9?2.3)% to (20.9?1.3)%(P=0.006) compared with plan 1.The trachea volume of(?)70 Gy(V_(70))in plan 3 was larger than that in plan 1[(20.3?15.9)% VS (10.5?9.8)%,P=0.058].Conclusion:For tumor at upper-thoracic,plan 1 and 2 were superior to plan 3.Irradiation to lung in plan 2 was lower than that in plan 1,but plan 1 improved the homogenous dose of PTV2 compared with plan 2,especially for patient with longer lesion.For tumor at upper-thoracic,plan 2 increased irradiation dose to lung compared with plan 1 and plan 3.Plan 1 was comparable with plan 3,but the dose of trachea in plan 1 may lower than that in plan 3.
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PURPOSE: To evaluate the roles of conventional radiotherapy alone or with neoadjuvant chemotherapy for tonsillar carcinomas and any prognostic factors affecting survivals by retrospective analysis. MATERIALS AND METHODS: Thirty four patients received radical radiotherapy for tonsillar carcinomas from Nov. 1985 to Dec. 1993. Of them, 16 patients were treated by conventional radiotherapy alone and the other 18 patients were received radiotherapy with 1 to 3 cycles of neoadjuvant chemotherapy of cisplatin and 5-fluorouracil or pepleomycin. Radiotherapy was performed by 6MV X-ray with daily fraction of 1.8Gy and the range of primary tumor doses was 55.0-86.4Gy(median 66.6Gy), and that of clinically positive nodal doses was 55.8-90Gy(median 69.7Gy). RESULTS: Overall 5-year actuarial survival rate (5YSR) was 32%. The 5YSRs in stage I+II(n=8), III(n=13) and IV(n=13) were 47%, 29% and 25%, respectively(p=0.33). The 5YSRs in T2(n=13), T3(n=10) and T4 (n=7) were 38%, 27% and 0%, respectively and 3 of 4 patients of T1 are alive with NED at 25, 45, 53 months respectively with statistical significance of the trend in survivals among the four T-stages(p=0.01), and those of node negative(n=14) vs node positive patients(n=20) were 31% vs 32%, respectively(p=0.85). There was no significant survival difference between radiotherapy alone group and with neoadjuvant chemotherapy group(22% vs. 38%, p=0.24). The 5YSRs of 21 patients of primary tumor extension to adjacent sites and the other 13 patients of tonsillar proper site were 28% and 38%, respectively but the difference was not significant statistically(p=0.62). There was a statistically significant difference in 5YSRs between the groups of the patients who received radiotherapy in less than 61days vs more than 60days(60% vs. 18%, p=0.027). All living patients without any tumor progression(n=11) had suffered from serious late sequelae such as xerostomia, edentia, dental caries and one patient had the osteoradionecrosis of mandible. On univariate analysis, the duration of radiotherapy and T-stage were the significant prognostic factors affecting 5YSR. On multivariate analysis, also the duration of radiotherapy was the only significant prognostic factor(p=0.01). CONCLUSION: There was no survival difference between the radiotherapy alone and with neoadjuvant chemotherapy groups. Although it was a retrospective study, the role of conventional radiotherapy alone could be effective as the local treatment modality only for the early stage of tonsillar carcinomas. But for the purpose of more improved survivals and better quality of lives of living patients, other altered fractionation such as hyperfractionated radiotherapy with shorter treatment time and smaller fraction size rather than conventional radiotherapy might be beneficial and these prospective studies are needed.
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Humans , Cisplatin , Dental Caries , Drug Therapy , Fluorouracil , Mandible , Multivariate Analysis , Osteoradionecrosis , Peplomycin , Radiotherapy , Retrospective Studies , Survival Rate , Tonsillar Neoplasms , XerostomiaABSTRACT
PURPOSE: To evaluate the role of MRI in the management of cervical cancer treated by conventional four-field whole pelvic irradiation. METHOD AND MATERIAL: Between 1993-march and 1994-february, 20 patients(4 Stage I B, 3 Stage U A, 13 Stage U B) with invasive cervical cancer were eligible for evaluation of accuracy of conventionally designed lateral treatment field without MRI determination. RESULTS: 5 out of 20 Patients had inadequate margin without MRI. The position of uterine fundus was more important than cervix in correction of field size and the center of treatment field. CONCLUSION: This Preliminary date show MRI determination of uterine position prior to radiotherapy planning is essential in the case of four-field whole pelvic irradiation technique.