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The Application of Dynamic Acquisition with Motion Correction for Static Image (동적 영상 획득 방식을 이용한 정적 영상의 움직임 보정)

  • Yoon, Seok-Hwan;Seung, Jong-Min;Kim, Kye-Hwan;Kim, Jae-Il;Lee, Hyung-Jin;Kim, Jin-Eui;Kim, Hyun-Joo
    • The Korean Journal of Nuclear Medicine Technology
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    • v.14 no.1
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    • pp.46-53
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    • 2010
  • Purpose: The static image of nuclear medicine study should be acquired without a motion, however, it is difficult to acquire static image without movement for the serious patients, advanced aged patients. These movements cause decreases in reliability for quantitative and qualitative analysis, therefore re-examination was inevitable in the some cases. Consequently, in order to improve the problem of motion artifacts, the authors substituted the dynamic acquisition technique for the static acquisition, using motion correction. Materials and Methods: A capillary tube and IEC body phantom were used. First, the static image was acquired for 60 seconds while the dynamic images were acquired with a protocol, 2 sec/frame${\times}$30 frames, under the same parameter and the frames were summed up into one image afterwards. Also, minimal motion and excessive motion were applied during the another dynamic acquisition and the coordinate correction was applied towards X and Y axis on the frames where the motion artifact occurred. But the severe blurred images were deleted. Finally, the resolution and counts were compared between the static image and the summed dynamic images which before and after applying motion correction, and the signal of frequency was analysed after frequency spatial domain was transformed into 2D FFT. Supplementary examination, the blind test was performed by the nuclear medicine department staff. Results: First, the resolution in the static image and summed dynamic image without motion were 8.32 mm, 8.37 mm on X-axis and 8.30 mm, 8.42 mm on Y-axis, respectively. The counts were 484 kcounts, 485 kcounts each, so there was nearly no difference. Secondly, the resolution in the image with minimal motion applying motion correction was 8.66 mm on X-axis, 8.85 mm on Y-axis and had 469 kcounts while the image without motion correction was 21.81 mm, 24.02 mm and 469 kcounts in order. So, this shows the image with minimal motion applying motion correction has similar resolution with the static image. Lastly, the resolution in the images with excessive motion applying motion correction were 9.09 mm on X-axis, 8.83 mm on Y-axis and had 469 kcounts while the image without motion correction was 47.35 mm, 40.46 mm and 255 kcounts in order. Although there was difference in counts because of deletion of blurred frames, we could get similar resolution. And when the image was transformed into frequency, the high frequency was decreased by the movement. However, the frequency was improved again after motion correction. In the blind test, there was no difference between the image applying motion correction and the static image without motion. Conclusion: There was no significant difference between the static image and the summed dynamic image. This technique can be applied to patients who may have difficulty remaining still during the imaging process, so that the quality of image can be improved as well as the reliance for analysis of quantity. Moreover, the re-examination rate will be considerably decreased. However, there is a limit of motion correction, more time will be required to successfully image the patients applying motion correction. Also, the decrease of total counts due to deletion of the severe blurred images should be calculated and the proper number of frames should be acquired.

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Radiotherapy Results in Stage IIB Uterine Cervix Cancer (자궁경부암 병기 IIB의 방사선치료결과)

  • Kil Whoon Jong;Chun Mison;Kang Seunghee;Oh Young Taek;Ryu Hee Sug;Ju Hee Jae;Lee Eun Ju
    • Radiation Oncology Journal
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    • v.19 no.4
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    • pp.345-352
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    • 2001
  • Purpose : To evaluate the treatment results and prognostic factors after radiotherapy in stage IIB uterine cervix cancer. Materials and methods : We retrospectively analyzed the records of 90 patients with stage IIB uterine cervix cancer who received radiotherapy between 9/94 and 12/99. Age was ranged from 28 to 79 years (median 57). Tumor size was $\geq4\;cm$ in 64 patients. Preteatment SCC level was measured in 75 patients. Twenty nine patients received conventional radiotherapy (QD) and the others received modified hyper-fractionated radiotherapy (BID). Only 7 patients in BID had tumor size <4 cm. All patients received high dose rate brachytherapy $(4\;Gy\times7\;or\;5\;Gy\times6)$. No Patient received concurrent chemotherapy during radiotherapy. Follow up period was ranging from 9 to 76 months (median 38). Results : The 5-year overall and disease free survival rates were $73.4\%\;and\;71.6\%$, respectively. Local recurrences occurred in $10\%$ of patients, and distant metastasis in $18.9\%$. There was a significant correlation between OS/DFS and tumor size $(<4cm;\;OS\;95.2\%,\;DFS\;91.4\%,\;\geq4cm;\;OS\;63.4\%,\;DFS\;63.4\%)$. Pretreatment SCC level was one of prognostic factors only in univariate analysis. Conclusion : With modified hyperfractionated radiotherapy, there was very low local recurrence rate $(6.6\%)$ and high 5-year overall and disease free survival rate $(75.4\%\;and\;70.5\%)$, which is comparable to results after concurrent chemoradiotherapy in bulky, locally advanced stage IIB uterine cervix cancer.

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The Results of Radiation Therapy in Locally Advanced Non-Small Cell Lung Cancer (국소적으로 진행된 비소세포폐암의 방사선치료 성적)

  • Kim Mi Sook;Yoo Seoung Yul;Cho Chul Koo;Yoo Hyung Joon;Kim Jae Young;Shim Jae Won;Lee Choon Taek;Kang Yoon Koo;Kim Tae You
    • Radiation Oncology Journal
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    • v.15 no.3
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    • pp.233-241
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    • 1997
  • Purpose : This study was done to evaluate the survival rate and Prognostic factors of patients with inoperable non-small cell lung cancer(NSCLC) treated with radiation therapy. Materials and Methods A retrospective analysis was undertaken of 62 Patients who had inoperable NSCLC treated with radiation therapy from January 1991 through December 1993. According to AJCC slaging, stage IIIA was 14 patients and stage IIIB was 48 patients. Forty Gy to 70.2Gy to the primary tumor site was delivered with daily fractions of 1.8Gy or 2Gy, 5days per week. Thirty-seven patients received neoadjuvant chemotherapy. Results : Complete, partial and no response to radiation therapy were 3 patients, 34 Patients and 25 patients, respectively The median survival period of all patients was 11 month. One rear survival rate, 2 year survival rateand 5 rear survival rate for all patients were 45.0%, 14.3%, and 6.0% respectively The median survival period was 6.5 months in stage IIIA and 13 months in stage IIIB. One year survival rates were 28.6% in stage IIIA and 50.3% in stage IIIB In univariaite analysis, prognostic factors affecting survival were T-s1aging, AJCC staging, and response after radiation therapy (P<0.05) . Pretreatment peformance status affected survival but was not statistically significant (0.050.1). In multivariate analysis, Pathology and response to radiation therapy are independently significant prognostic factor. T stage was marginally significant (P=0.0809). During follow-up duration, distant metastasis developed in 20 patients-bone metastasis in 10 patients, brain metastasis in 3 patients, liver mentastasis in 3 patients, contralateral lung metastasis in 1 patients and multiple metastases in 3 patients. Conclusion : Conventional radiotherapy alone or combined chemoradiotherapy are unlikely to achieve long term survival in patients with NSCLC. Surgery after concurrent chemoradiotherapy is Ivied to improve the local control in our hospital

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The Study of Normal Tissue Complication Probability(NTCP) for Radiation Pneumonitis by Effective Volume Method (유효체적 방법과 임상분석을 통한 방사선에 의한 정상 폐조직의 부작용 확률에 관한 연구)

  • Ahn Seung Do;Choi Eun Kyung;Yi Byong Yong;Chang Hyesook
    • Radiation Oncology Journal
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    • v.15 no.3
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    • pp.243-249
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    • 1997
  • Purpose : In radiation therapy, NTCF is very importart indicator of selecting the optimal treatment plan. In our study, we tried to find out usefullness of NTCP in lung cancer by comparng the incidence of radiation pneumonitis with NTCP. Materials and Methods : From August 1993 to December 1994, thirty six patients with locally advanced non=small cell lung cancer were treated by concurrent chemoradiation therapy. Total dose of radiation therapy was 6480cGy (120cGy, bid) and chemotherapeutlc agents were mitomycin C. vinblastion, cisplatin (2 cycles, 4 weeks interval). We evaluated the development of raniation pneumonitis by CT scan, chest x-rar and clinical symptoms. We used grading system of South Western Oncology Group (SWOG) for radiation pneumanitis. Dose Volume Histograms (DVH) were analyzed for ipsilateral and whole lung, Non uniform DVH was translated to uniform DVH by effective volume method. With these data, we calculated NTCP for ipsilateral and whole lung. Finally we compared the clinical results to NTCP. Results : Eight of thrity six patients developed radiation pneumonitis. Of these 8 patients , 6 had grade I severity and 2 had grade II. The average NTCP value cf the patients who showed radiation pneumonitis was significantly higher than that uf the patients without pneumonitis $(66\%\;vs.\;26.4\%)$. But the results of pulmonary function test was not correlated with NTCP. Conclusion : NTCP of lung is very good indicator for selecting rival treatment planning in lung cancer. According to the results of NTCP, it may be possible to adjust target volume and optimize target dose. In the near future, we are going to anaiyze the effect of hyperfractionation and concurrent chemotherapy in addition to NTCP.

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A Comparative Study of Stenting versus Surgical Bypass in Gastric Outlet Obstruction Caused by Gastric Cancer (위암 날문부 폐쇄 환자에게 시행한 치료의 비교고찰: 위-공장 우회술과 금속성 자가팽창성 스텐트 삽입술)

  • Jo, Seung-Jin;Yoon, Ki-Young;Choi, Kyung-Hyun;Park, Moo-In;Park, Seun-Ja;Ko, Ji-Ho;Lee, Sang-Ho
    • Journal of Gastric Cancer
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    • v.7 no.2
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    • pp.82-87
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    • 2007
  • Purpose: In gastric cancer patients with gastric outlet obstruction, there are several complications such as malnutrition and vomiting. Palliative enteral stenting is a less invasive procedure as compared with a gastrojejunostomy. The aim of this study was to determine whether there was a significant difference between patients that undergone palliative enteral slanting and patients that had received a bypass gastrojejunostomy. Materials and Methods: One hundred patients underwent palliative entering stenting and 3f patients were subjected to a surgical bypass gastrojejunostomy. We reviewed the medical records of the patients with gastric outlet obstruction secondary to far advanced gastric cancer that were diagnosed using a gastrofibroscope, UGI and abdominal CT, and were admitted to our institution between January 2000 and August 2006. The outcome of stent placement for gastric outlet obstruction was compared with palliative gastrojejunostomy during the same period. We excluded patients with recurrent gastric cancer and double cancer from this study. Results: There were significant differences between the group of patients that underwent slanting and the group of patients that received a gastrojejunostomy regarding the age of patients ($67{\pm}12$ vs. $57{\pm}9$, P<0.001) but not between the sex of the patients (M : F, 2 : 1 vs. 2 :1, P=0.637). The most common complication of stenting was tumor ingrowth (16/100, 16%) and the second most common complication was stent migration (14/100). Failure of the procedure occurred in only three patients. Twenty-three patients underwent re-slanting and one patient required open conversion with a gastrojejunostomy. The median time to the first meal was $4{\pm}2$ days in the stent group of patients and $6{\pm}2$ days in the gastrojejunostomy group of patients (P=0.001). The median postoperative hospital stays were 9 days in the stent group of patients and 15 days in the gastrojejunostomy group of patients (P=0.003). The mean survival periods were 11 months in the stent group of patients and 10 months in the gastrojejunostomy group of patients (P=0.937). Conclusion: There were no significant differences In the mean survival rates. An earlier first meal and a shorter hospitalization stay were found in the slanting group of patients compared to the bypass gastrojejunostomy group of patients. However, re-slanting was a concern due to tumor ingrowth and stent migration.

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A Study on LRFD Reliability Based Design Criteria of RC Flexural Members (R.C. 휨부재(部材)의 L.R.F.D. 신뢰성(信賴性) 설계기준(設計基準)에 관한 연구(研究))

  • Cho, Hyo Nam
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.1 no.1
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    • pp.21-32
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    • 1981
  • Recent trends in design standards development in some European countries and U.S.A. have encouraged the use of probabilistic limit sate design concepts. Reliability based design criteria such as LSD, LRFD, PBLSD, adopted in those advanced countries have the potentials that they afford for symplifying the design process and placing it on a consistent reliability bases for various construction materials. A reliability based design criteria for RC flexural members are proposed in this study. Lind-Hasofer's invariant second-moment reliability theory is used in the derivation of an algorithmic reliability analysis method as well as an iterative determination of load and resistance factors. In addition, Cornell's Mean First-Order Second Moment Method is employed as a practical tool for the approximate reliability analysis and the derivation of design criteria. Uncertainty measures for flexural resistance and load effects are based on the Ellingwood's approach for the evaluation of uncertainties of loads and resistances. The implied relative safety levels of RC flexural members designed by the strength design provisions of the current standard code were evaluated using the second moment reliability analysis method proposed in this study. And then, resistance and load factors corresponding to the target reliability index(${\beta}=4$) which is considered to be appropriate level of reliability considering our practices are calculated by using the proposed methods. These reliability based factors were compared to those specified by our current ultimate strength design provisions. It was found that the reliability levels of flexural members designed by current code are not appropriate, and the code specified resistance and load factors were considerably different from the reliability based resistance and load factors proposed in this study.

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Clinical Aspects of Pulmonary Radioactivity Observed in Radiocolloid Liver Scintigraphy (간 스캔에서 관찰되는 폐 방사능에 관한 임상적 고찰)

  • So, Young;Lee, Kang-Wook;Lee, Heon-Young;Lee, Won-Woo
    • The Korean Journal of Nuclear Medicine
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    • v.36 no.3
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    • pp.185-194
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    • 2002
  • Purpose: We studied clinical aspects and courses of patients with pulmonary radioactivity on liver scintigraphy and speculated the mechanism of pulmonary uptake of radiocolloids. Materials and Methods: Forty-nine patients with pulmonary radioactivity were classified into 5 disease groups-liver disease, infection, cancer, ischemic necrosis of liver, etc.- and their presence or absence of chronic liver disease (CLD), Child-Pugh class, serum levels of AST and ALT, results of follow-up liver scintigraphy and clinical course were checked. Results: Of total 49 patients 25 had CLD; there were 23 liver disease patients, 16 infection patients, 7 advanced cancer patients, 2 ischemic necrosis of liver patients, and 1 hemolytic anemia patient. Reversible rise of serum levels of AST and ALT was observed in all patients with liver disease and ischemic necrosis of liver; on one-way ANOVA, these rise were statistically significant (p<0.01). Serum level of ALT of liver disease group patients without CLD was significantly higher than that of infection group patients without CLD (p<0.05). Among 17 patients who underwent follow-up liver scintigraphy, 13 showed no pulmonary radioactivity. Total 12 patients died during follow-up and most of them were terminal cancer patients or CLD patients of Child-Pugh class C. Conclusion: Pulmonary radioactivity of radiocolloid liver scintigraphy could be attributed to the mobilization of reticuloendothelial system (RES) cells by the activation of RES cells in severe infection and terminal cancer, and also by the extensive liver destruction in liver diseases.

Microarray Analysis of Long Non-coding RNA Expression Profile Associated with 5-Fluorouracil-Based Chemoradiation Resistance in Colorectal Cancer Cells

  • Xiong, Wei;Jiang, Yong-Xin;Ai, Yi-Qin;Liu, Shan;Wu, Xing-Rao;Cui, Jian-Guo;Qin, Ji-Yong;Liu, Yan;Xia, Yao-Xiong;Ju, Yun-He;He, Wen-Jie;Wang, Yong;Li, Yun-Fen;Hou, Yu;Wang, Li;Li, Wen-Hui
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.8
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    • pp.3395-3402
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    • 2015
  • Background: Preoperative 5-fluorouracil (5-FU)-based chemoradiotherapy is a standard treatment for locally advanced colorectal cancer (CRC). However, CRC cells often develop chemoradiation resistance (CRR). Recent studies have shown that long non-coding RNA (lncRNA) plays critical roles in a myriad of biological processes and human diseases, as well as chemotherapy resistance. Since the roles of lncRNAs in 5-FU-based CRR in human CRC cells remain unknown, they were investigated in this study. Materials and Methods: A 5-FU-based concurrent CRR cell model was established using human CRC cell line HCT116. Microarray expression profiling of lncRNAs and mRNAs was undertaken in parental HCT116 and 5-FU-based CRR cell lines. Results: In total, 2,662 differentially expressed lncRNAs and 2,398 mRNAs were identified in 5-FU-based CRR HCT116 cells when compared with those in parental HCT116. Moreover, 6 lncRNAs and 6 mRNAs found to be differentially expressed were validated by quantitative real time PCR (qRT-PCR). Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis for the differentially expressed mRNAs indicated involvement of many, such as Jak-STAT, PI3K-Akt and NF-kappa B signaling pathways. To better understand the molecular basis of 5-FU-based CRR in CRC cells, correlated expression networks were constructed based on 8 intergenic lncRNAs and their nearby coding genes. Conclusions: Changes in lncRNA expression are involved in 5-FU-based CRR in CRC cells. These findings may provide novel insight for the prognosis and prediction of response to therapy in CRC patients.

Irradiation Alone in Stage IB, IIA, and IIB Cervix Cancer : I Analysis of Survival and Failure Patterns (자궁경부암 병기 IB, IIA, IIB에서 방사선 단독치료성적 : I 생존기간 및 재발양상에 관한 분석)

  • Ahn Sung Ja;Chung Woong Ki;Nah Byung Sik;Nam Taek Keun;Choi Ho Sun;Byun Ji Soo
    • Radiation Oncology Journal
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    • v.15 no.2
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    • pp.129-136
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    • 1997
  • Purpose : We analyzed the survival and failure patterns of cervix cancer patients treated with irradiation alone to evaluate our treatment method and to compare with the others Methods and Materials : Two hundred and twenty cervical cancer patients, Stage IB, II A, and II B who completed the planned treatment between Mar 1987 and December 1991 were analyzed retrospectively. The Stage IB patients were restaged to the Stage IB1 and IB2 by the recently revised FIGO classification, Patients were treated with a combination of external irradiation and the intracavitary brachytherapy Determination of the tumor control was done at the time of 6 months Postirradiation. The follow-up time was ranged from 3 to 115 months and the mean was 62 months and the follow-up rate was $93.6\%$(206/220) Results : The overall 5-year survival rate of Stage IB1 (N=50), IB2(N: 15). II A(N=58), and II B(N=97) was $94\%,\;87\%,\;69\%,\;and\;56\%$. respectively. In the univariate analysis of prognostic factors, stage(0.00), initial Hg level (P=0.00), initial TA-4(tumor-associated) antigen level(p= 0.02), initial CEA level(p=0.02), barrel-shaped tumor(p=0.02), whole cervical involvement (0.00), pelvic tyrnphadenopathy(LAP) in CT(p=0.04), and Post-irradiation adiuvant chemotherapy(P=0.00) were statistically significant in survival analysis. In a while multivariate analysis showed that the stage was the most powerful Prognostic indicator and the Post-irradiation chemotherapy factor also showed the statistical significance. The overall local control rate was $81\%$ and by the stage, $100\%$ in Stage IBI, $86.7\%$ in Stage IBS, $84.5\%$ in Stage IIA, and $68.1\%$ in Stage IIB, respectively The overall tumor recurrence rate was $15.5\%$(27/174) and by the stage, $8\%$(4/50) in Stage IB1, $0\%$(0/l3) in Stage IB2, $22.4\%$(l1/49) in Stage II A, and $19.4\%$(12/62) in Stage II B, respectively. Conclusions : We obtained the similar treatment results to the other's ones in early stage cervical cancer patients. But in Stage II B, the local control rate was lower than that of the other institutes and also the survival was poorer. So it seems to be necessary to reevaluate the treatment method in advanced cervical cancer patients.

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Analysis of Prognostic Factors in Patients with Carcinoma of Uterine Cervix (자궁경부암의 방사선치료시 예후인자의 재분석)

  • Kim Jae Young;Cho Chul Koo;Shim Jae Won;Yoo Seong Yul;Kim Mi Sook;Yun Hyong Geun
    • Radiation Oncology Journal
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    • v.14 no.4
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    • pp.307-315
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    • 1996
  • Purpose : The authors conducted a retrospective analysis of patients with the carcinoma of uterine cervix treated with curative radiation therapy to evaluate the prognostic factors that would affect the results of the therapy and to get the critical ideas in determining more aggressive treatment schedule. Methods and Materials : From January 1987 to December 1988. Four hundreds and sixty patients with uterine cervical carcinomas treated with radiotherapy at KCCH were registered to this retrospective study. One hundred and three patients were treated with external radiation therapy alone, and 357 patients were treated with external radiation followed by low dose rate intracavitary radiation therapy. The follow-up rate was 88% and median follow-up duration was 48 months. Results : The overall 5 year survival rate of the patients was 67.7%, and when classified by FIGO stages, 5 year survival rates were 81.2%, 76.3%, 73.1%, 50%. 52.3%, 11.5% for stages Ib, IIa, IIb, IIIa, IVa respectively. Tumor size(p=0.0002), endocervical growth pattern(p=0.003), lymph node invasion(p=0.0001), mean hemoglobin level(p=0.0001), and pathologic cell type(p=0.0001) were significant prognostic factors and decrease in survival for young age patient group was marginally important (p=0.03). Conclusion : Significant prognostic factors in the radiation therapy of the uterine cervical carcinoma were tumor size, growth pattern of tumor, lymph node invasion, pathologic cell type, hemoglobin level of patients during treatment and lower survival rate in young age group was obvious, too. Patients with large size tumor(${\geq)$4cm), especially combined with endocervical growth patterns or advanced stages(III or more) need more aggressive treatment to improve the outcome of treatment. And positive feature of lymph node invasion affected the result of therapy, so improvement in the diagnostic and therapeutic trial is essential.

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