• Title/Summary/Keyword: Dose-rate

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Application of Environmental Friendly Bio-adsorbent based on a Plant Root for Copper Recovery Compared to the Synthetic Resin (구리 회수를 위한 식물뿌리 기반 친환경 바이오 흡착제의 적용 - 합성수지와의 비교)

  • Bawkar, Shilpa K.;Jha, Manis K.;Choubey, Pankaj K.;Parween, Rukshana;Panda, Rekha;Singh, Pramod K.;Lee, Jae-chun
    • Resources Recycling
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    • v.31 no.4
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    • pp.56-65
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    • 2022
  • Copper is one of the non-ferrous metals used in the electrical/electronic manufacturing industries due to its superior properties particularly the high conductivity and less resistivity. The effluent generated from the surface finishing process of these industries contains higher copper content which gets discharged in to water bodies directly or indirectly. This causes severe environmental pollution and also results in loss of an important valuable metal. To overcome this issue, continuous R & D activities are going on across the globe in adsorption area with the purpose of finding an efficient, low cost and ecofriendly adsorbent. In view of the above, present investigation was made to compare the performance of a plant root (Datura root powder) as a bio-adsorbent to that of the synthetic one (Tulsion T-42) for copper adsorption from such effluent. Experiments were carried out in batch studies to optimize parameters such as adsorbent dose, contact time, pH, feed concentration, etc. Results of the batch experiments indicate that 0.2 g of Datura root powder and 0.1 g of Tulsion T-42 showed 95% copper adsorption from an initial feed/solution of 100 ppm Cu at pH 4 in contact time of 15 and 30 min, respectively. Adsorption data for both the adsorbents were fitted well to the Freundlich isotherm. Experimental results were also validated with the kinetic model, which showed that the adsorption of copper followed pseudo-second order rate expression for the both adsorbents. Overall result demonstrates that the bio-adsorbent tested has a potential applicability for metal recovery from the waste solutions/effluents of metal finishing units. In view of the requirements of commercial viability and minimal environmental damage there from, Datura root powder being an effective material for metal uptake, may prove to be a feasible adsorbent for copper recovery after the necessary scale-up studies.

Effects for Growth and Chlorophyll in Old-barley and New-barley Seed exposed by X-ray (X-선이 묵은보리 씨앗과 햇보리 씨앗의 생장과 클로로필 농도에 미치는 영향)

  • Sang-Bok, Jeong;Sun-Cheol, Jeong;Mo-Kwon, Lee;Yun-Ho, Choi;Kang-Un, Byun;Su-Ah, Yu;Sang-Eun, Han;Jun-Beom, Heo;Wan-Sik, Shin;Won-Jeong, Lee
    • Journal of the Korean Society of Radiology
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    • v.17 no.1
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    • pp.149-156
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    • 2023
  • The purpose of this study is to compare of growth and chlorophyl between old-barley seed (OBS, 2019) and New-barley seed (NBS, 2020) exposed by X-ray. After germination the OBS and NBS, experimental group was exposed by 30 Gy X-ray using linear accelerator (Clinac IS, VERIAN, USA), by 6 MV X-ray, SSD 100 cm, 18 × 10 cm2, 600 MU/min. Length was measured every day until 9th day, and chlorophyl was analyzed using spectrophotometer(uv-1800, shimadzu, japan) after measuring weight in 9th day. Data analysis was performed the Independent T-test using SPSS ver 26.0(Chicago, IL, USA). NBS grow more faster than OBS in control group, but OBS grow more faster than NBS in experimental group. Length of control group was longer significantly every day than that of experimental group in OBS. NBS weighted more than OBS in control group, but OBS weighted more than NBS in experimental group. In comparing chlorophyl density, NBS high more than OBS in control group as well as experimental group. Growth and weight of OBS was effected more those than NBS by X-ray, but NBS in chlorophyl by X-ray. It is expected to be used as basic data for future X-ray research in barley seed.

Heavy concrete shielding properties for carbon therapy

  • Jin-Long Wang;Jiade J Lu;Da-Jun Ding;Wen-Hua Jiang;Ya-Dong Li;Rui Qiu;Hui Zhang;Xiao-Zhong Wang;Huo-Sheng Ruan;Yan-Bing Teng;Xiao-Guang Wu;Yun Zheng;Zi-Hao Zhao;Kai-Zhong Liao;Huan-Cheng Mai;Xiao-Dong Wang;Ke Peng;Wei Wang;Zhan Tang;Zhao-Yan Yu;Zhen Wu;Hong-Hu Song;Shuo-Yang Wei;Sen-Lin Mao;Jun Xu;Jing Tao;Min-Qiang Zhang;Xi-Qiang Xue;Ming Wang
    • Nuclear Engineering and Technology
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    • v.55 no.6
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    • pp.2335-2347
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    • 2023
  • As medical facilities are usually built at urban areas, special concrete aggregates and evaluation methods are needed to optimize the design of concrete walls by balancing density, thickness, material composition, cost, and other factors. Carbon treatment rooms require a high radiation shielding requirement, as the neutron yield from carbon therapy is much higher than the neutron yield of protons. In this case study, the maximum carbon energy is 430 MeV/u and the maximum current is 0.27 nA from a hybrid particle therapy system. Hospital or facility construction should consider this requirement to design a special heavy concrete. In this work, magnetite is adopted as the major aggregate. Density is determined mainly by the major aggregate content of magnetite, and a heavy concrete test block was constructed for structural tests. The compressive strength is 35.7 MPa. The density ranges from 3.65 g/cm3 to 4.14 g/cm3, and the iron mass content ranges from 53.78% to 60.38% from the 12 cored sample measurements. It was found that there is a linear relationship between density and iron content, and mixing impurities should be the major reason leading to the nonuniform element and density distribution. The effect of this nonuniformity on radiation shielding properties for a carbon treatment room is investigated by three groups of Monte Carlo simulations. Higher density dominates to reduce shielding thickness. However, a higher content of high-Z elements will weaken the shielding strength, especially at a lower dose rate threshold and vice versa. The weakened side effect of a high iron content on the shielding property is obvious at 2.5 µSv=h. Therefore, we should not blindly pursue high Z content in engineering. If the thickness is constrained to 2 m, then the density can be reduced to 3.3 g/cm3, which will save cost by reducing the magnetite composition with 50.44% iron content. If a higher density of 3.9 g/cm3 with 57.65% iron content is selected for construction, then the thickness of the wall can be reduced to 174.2 cm, which will save space for equipment installation.

Effect of Fractionated X-ray Irradiation on Sprouted Barley Growth and Chlorophyll Concentration (X선의 분할조사가 새싹보리 생장과 클로로필 농도에 미치는 영향)

  • In Suck Park;Won-Jeong Lee;Sang-Bok Jeong
    • Journal of the Korean Society of Radiology
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    • v.17 no.7
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    • pp.1171-1178
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    • 2023
  • In study, we investigated changes on growth and chlorophyll concentration on sprouted barley by fractionated X-ray irradiation (FXI). Group was divided into the control group (CG), 1-time irradiation group (30 Gy once), 2-time irradiation group (15 Gy 2 times), and 3-time irradiation group (10 Gy 3 times), and 20 grains were used per group. Experimental group (EG) was exposed by using linear accelerator (Clinac IS, VERIAN, USA), by 6 MV X-ray, SSD 100 cm, 18×10 cm2, 600 MU/min. Length was measured every day until 9th day, and chlorophyl was analyzed using spectrophotometer(uv-1800, shimadzu, japan) in 9th day. Data analysis was performed the One-way ANOVA using SPSS ver 26.0(Chicago, IL, USA). In the pre-germination irradiation group (Pre-GIG), the CG had greater length than the EG on all measurement days, and as the number of FXI increased, the length became shorter. In the post-germination irradiation group (Post-GIG), the length of the CG was statistically significantly greater than that of the EG on all measurement days, and as the number of FXI increased, the length also became longer. The chlorophyll concentration was higher in the Post-GIG than in the Pre-GIG, and chlorophyll concentrations of EG was higher in the Pre-GIG than in the CG, as well as and Post-GIG. In addition, the smaller the number of FXI, the higher the chlorophyll concentration in both groups. FXI was found to affect the growth and chlorophyll concentration of sprouted barley.

Reversal of Multidrug Resistance with KR-30035: Evaluated with Biodistribution of Tc-99m MIBI in Nude Mice Bearing Human Tumor Xenografts (이종이식된 인체종양에서 KR-30035가 Tc-99m MIBI체내 분포에 미치는 영향으로 평가한 다약제내성 역전가능성)

  • Kim, Jung-Kyun;Lee, Byung-Ho;Choi, Sang-Woon;Yoo, Sung-Eun;Lee, Sang-Woo;Chun, Kyung-Ah;Ahn, Byeong-Cheol;Park, Jae-Young;Suh, Jang-Soo;Lee, Kyu-Bo;Lee, Jae-Tae
    • The Korean Journal of Nuclear Medicine
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    • v.35 no.3
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    • pp.168-184
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    • 2001
  • Purpose: KR-30035 (KR), a new MDR reversing agent, has been found to produce a similar degree of increased Tc-99m MIBI uptake in cultured tumor cells over-expressing mdr1 mRNA compared to verapamil (VP), with less cardiovascular effects. We assessed the MDR-reversing ability of KR in vivo, and effects of various doses of KR on MIBI uptake un nude mice hearing P-glycoprotein (P-gp) positive (+) and P-gp negative (-) human tumor xenografts. Methods: P-gp (+) HCT15/CL02 colorectal and P-gp (-) A549 non-small cell cancer cells were inoculated in each flank of 120 nude mice (20 mice ${\times}$ 6 groups). Group 1 (Gr1) mice received 10mg/kg KR i.p. 3 times $({\times}3)$; Gr2, 10mg/kg VP i.p. ${\times}3$; Gr3, 10mg/kg KR i.p. ${\times}2$ + 25mg/kg KR i.p. ${\times}1$; Gr4, 10mg/kg KR i.p. ${\times}2$ + 50mg/kg i.p. ${\times}1$; Gr5, 10mg/kg KR i.p. ${\times}2$ + 25mg/kg KR i.v. ${\times}1$, GrC, controls. The mice were then injected with Tc-99m MIBI and sacrificed after 10 min, 30 min, 90 min and 240 min. Tumor uptake of MIBI (TU) in each group was compared. Results: TU in P-gp (+) and (-) tumors were both higher in Gr1 than Gr2. Washout rate between the 10 min and 4 hours was lower in Gr5 of P-gp (+) cell(0.93) than the control. Percentage increases in TU were higher in P-gp (+) than P-gp (-) tumors with all KR doses. Pgp (+) TU were highest at 10 mon (173% of GrC) and persisted up to 240 min (144%) in Gr3. Larger doses of KR resulted in a lesser degree of increase in P-gp (+) TU at 10 min (130% in Gr4 and 117% un Gr5) and 30 min (178%, 129%), but TU increased by time up to 240 min (177%, 196%). Heart and lung uptakes were markedly increased in Gr4 and Gr5 at 10 and 30 min, likely due to cardiovascular effects. No mice died. Conclusion: These data further suggest that KR that has significantly lower cardiovascular toxicity than verapamil can be used as an active inhibitor of MDR. Even a relatively low dose of KR significantly increased Tc-99m MIBI uptake in P-gp (+) tumors in vivo.

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A Study on measurement of scattery ray of Computed Tomography (전산화 단층촬영실의 산란선 측정에 대한 연구)

  • Cho, Pyong-Kon;Lee, Joon-Hyup;Kim, Yoon-Sik;Lee, Chang-Yeop
    • Journal of radiological science and technology
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    • v.26 no.2
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    • pp.37-42
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    • 2003
  • Purpose : Computed tomographic equipment is essential for diagnosis by means of radiation. With passage of time and development of science computed tomographic was developed time and again and in future examination by means of this equipment is expected to increase. In this connection these authors measured rate of scatter ray generation at front of lead glass for patients within control room of computed tomographic equipment room and outside of entrance door for exit and entrance of patients and attempted to ind out method for minimizing exposure to scatter ray. Material and Method : From November 2001 twenty five units of computed tomographic equipments which were already installed and operation by 13 general hospitals and university hospitals in Seoul were subjected to this study. As condition of photographing those recommended by manufacturer for measuring exposure to sauter ray was use. At the time objects used DALI CT Radiation Dose Test Phantom fot Head (${\oint}16\;cm$ Plexglas) and Phantom for Stomache(${\oint}32\;cm$ Plexglas) were used. For measurement of scatter ray Reader (Radiation Monitor Controller Model 2026) and G-M Survey were used to Survey Meter of Radical Corporation, model $20{\times}5-1800$, Electrometer/Ion Chamber, S/N 21740. Spots for measurement of scatter ray included front of lead glass for patients within control room of computed tomographic equipment room which is place where most of work by gradiographic personnel are carried out and is outside of entrance door for exit and entrance of patients and their guardians and at spot 100 cm off from isocenter at the time of scanning the object. The results : Work environment within computed tomography room which was installed and under operation by each hospital showed considerable difference depending on circumstances of pertinent hospitals and status of scatter ray was as follows. 1) From isocenter of computed tomographic equipment to lead glass for patients within control room average distance was 377 cm. At that time scatter ray showed diverse distribution from spot where no presence was detected to spot where about 100 mR/week was detected. But it met requirement of weekly tolerance $2.58{\times}10^{-5}\;C/kg$(100 mR/week). 2) From isocenter of computed tomographic equipment to outside of entrance door where patients and their guardians exit and enter was 439 cm in average, At that time scatter ray showed diverse distribution from spot where almost no presence was detected to spot with different level but in most of cases it satisfied requirement of weekly tolerance of $2.58{\times}10^{-6}\;C/kg$(100 mR/week). 3) At the time of scanning object amount of scatter ray at spot with 100 cm distance from isocenter showed considerable difference depending on equipments. Conclusion : Use of computed tomographic equipment as one for generation of radiation for diagnosis is increasing daily. Compared to other general X-ray photographing field of diagnosis is very high but there is a high possibility of exposure to radiation and scatter ray. To be free from scatter ray at computed tomographic equipment room even by slight degree it is essential to secure sufficient space and more effort should be exerted for development of variety of skills to enable maximum photographic image at minimum cost.

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Radioprotective Effects of Granulocyte-Colony Stimulating Factor in the Jejunal Mucosa of Mouse (생쥐에서 과립구 집락형성인자(Granulocyte-Colony Stimulating Factor)의 공장점막에 대한 방사선 보호효과)

  • Ryu, Mi-Ryeong;Chung, Su-Mi;Kay, Chul-Seung;Kim, Yeon-Shil;Yoon, Sei-Chul
    • Radiation Oncology Journal
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    • v.19 no.1
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    • pp.45-52
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    • 2001
  • Purpose : Granulocyle-colony stimulating factor (G-CSF) has been widely used to treat neutropenia caused by chemotherapy or radiotherapy. The efficacy of recombinant human hematopoietic growth factors in improving oral mucositis after chemotherapy or radiotherapy has been recently demonstrated in some clinical studies. This study was designed to determine whether G-CSF can modify the radiation injury of the intestinal mucosa in mice. Materials and Methods : One hundred and five BALB/c mice weighing 20 grams were divided into nine subgroups including G-CSF alone group $(I:10\;{\mu}g/kg\;or\;II:100\;{\mu}g/kg)$, radiation alone group (7.5 or 12 Gy on the whole body), combination group with G-CSF and radiation (G-CSF I or II plus 7.5 Gy, G-CSF I or II plus 12 Gy), and control group. Radiation was administered with a 6 MV linear accelerator (Mevatron Siemens) with a dose rate of 3 Gy/min on day 0. G-CSF was injected subcutaneously for 3 days, once a day, from day -2 to day 0. Each group was sacrificed on the day 1, day 3, and day 7. The mucosal changes of jejunum were evaluated microscopically by crypt count per circumference, villi length, and histologic damage grading. Results : In both G-CSF I and II groups, crypt counts, villi length, and histologic damage scores were not significantly different from those of the control one (p>0.05). The 7.5 Gy and 12 Gy radiation alone groups showed significantly lower crypt counts and higher histologic damage scores compared with those of control one (p<0.05). The groups exposed to 7.5 Gy radiation plus G-CSF I or II showed significantly higher crypt counts and lower histologic damage scores on the day 3, and lower histologic damage scores on the day 7 compared with those of the 7.5 Gy radiation alone one (p<0.05). The 12 Gy radiation plus G-CSF I or II group did not show significant difference in crypt counts and histologic damage scores compared with those of the 12 Gy radiation alone one (p>0,05). Most of the mice in 12 Gy radiation with or without G-CSF group showed intestinal death within 5 days. Conclusion : These results suggest that G-CSF may protect the jejunal mucosa from the acute radiation damage following within the tolerable ranges of whole body irradiation in mice.

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Therapeutic Results of Radiotherapy in Rectal Carcinoma - Comparison of Sandwich Technique Radiotherapy with Postoperative Radiotherapy (직장암의 방사선 치료 결과 - Sandwich Technique 방사선 치료와 수술후 방사선 치료의 비교)

  • Huh Cil Cha;Suh Hyun Suk;Lee Hyuk Sang;Kim Re Hwe;Kim Chul Soo;Kim Hong Yong;Kim Sung Rok
    • Radiation Oncology Journal
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    • v.14 no.1
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    • pp.25-31
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    • 1996
  • Purpose : To evaluate the potential advantage for 'sandwich' technique radiotherapy compared to Postoperative radiotherapy in resectable rectal cancer. Materials and Methods : Between January 1989 and Mar 1994, 60 patients with resectable rectal cancer were treated at Inje University Seoul and Sanggye Paik Hospital. Fifty one patients were available for analysis: 20 patients were treated with sandwich technique radiotherapy and 31 patients were treated with Postoperative radiotherapy. In sandwich technique radiotherapy(RT), Patients were treated with preoperative RT 1500 cGy/5fx, followed by immediate curative resection. Patients staged as Astler-Coiler B2, C were considered for postoperative RT with 2500-4500 cGy. in postoperative RT total radiation dose of 4500-6120 cGy, 180 cGy daily at 4-Sweets was delivered. Patients were followed for median period of 25 months. Results : The overall 5-year survival rates for sandwich RT group and postoperative RT group were $60\%$ and $71\%$, respectively(p>0.05). The 5-rear disease free survival rates for each group were $63\%$. There was no difference in local failure rate between two groups($11\%$ versus $7\%$) Incidence of distant metastasis was $11\%$(2/20) in the sandwich technique RT group and $20\%$(6/31) in the postoperative RT group(p>0.05). The frequencies of acute and chronic complications were comparable in both groups. Conclusion : The sandwich technique radiotherapy group shows local recurrence and survival similar to those of Postoperative RT alone group but reduced distant metastasis compared to Postoperative RT group. But long term follow-up and large number of patients is needed to make an any firm conclusion regarding the value of this sandwich technique RT.

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Combined Chemoradiotherapy vs Radiotherapy Alone for Locally Advanced Squamous Cell Carcinoma of the Head and Neck (국소적으로 진행된 두경부 편평상피세포종양의 방사선- 항암화학 병용요법과 방사선단독치료의 비교)

  • Jeong, Hyeon-Ju;Suh, Hyun-Suk;Kim, Chul-Soo;Kim, Re-Hwe;Kim, Sung-Rok
    • Radiation Oncology Journal
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    • v.14 no.1
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    • pp.9-15
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    • 1996
  • Purpose: The traditional approach with surgery and/or radiotherapy(RT) for advanced head and neck cancer Provides anticipated cure rates of $10-65\%$ depending on stages and sites. Recently, combined modality with chemotherapy have been extensively investigated in attempts to improve survival and local control. We retrospectively analysed our experience of 31 patients with advanced head and neck cancer. Materials and Methods : November 1983 to October 1994. 31 Patients with Stage III and IV squamous cell head and neck cancer were treated with RT. Sixteen patients were treated with RT alone, and IS patients were treated with combined RT plus chemotherapy. All patients were treated with 4-MV LINAC and radiation dose ranged from 5000 cGy to 7760 cGy (median 7010 cGy). In combined group, 7 patients were treated with cisplatin plus 5-FU 2 patients were treated with methotrexate plus leucovorin plus 5-FU plus cisplatin or carboplatin, and 6 patients were treated with cisplatin as a radiosensitizer. Results : Median follow up period was 16 months (range 4-134 months). The major responses (CR+PR) were noted in 10 patient ($66.6\%$) of the RT alone group and 14 patient ($93.3\%$) of the chemoradiation group. There was no statistical difference in CR rate between the two groups The overall survival rates at 5 years were $23.4\%$ in the radiation alone group, $23.5\%$ in the chemoradiation group Disease-free survival rates at 3 years were $44.5\%$ in the radiation alone group, $40\%$ in the chemoradiation group. There was no statistical differences in overall survival rates and disease-free survival rates between the two groups. Local recurrences occurred in $71.5\%$ of the radiation alone group, $72.7\%$ of the chemoradiation group and distant metastasis occurred in $14.4\%$ of radiation alone group, $9.1\%$ of the chemoradiation group. The frequencies of complications were comparable in both groups except hematologic toxicity Conclusion : Total response rates in the combined chemotherapy and radiotherapy was relatively higher than radiotherapy alone. But our result failed to show any survival benefit of the combined chemotherapy and radiotherapy. The accrual of large number of patients and long term follow-un may be necessary to confirm the present result of combined chemotherapy and radiotherapy.

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The Role of Postoperative Adjuvant Radiotherapy in Resected Esophageal Cancer (식도암에서 근치적 절제술 후 방사선치료의 역할)

  • Lee Chang Geol;Kim Choong Bae;Chung Kyung Young;Lee Doo Yun;Seong Jinsil;Kim Gwi Eon;Suh Chang Ok
    • Radiation Oncology Journal
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    • v.20 no.4
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    • pp.316-322
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    • 2002
  • Objective : A retrospective study was peformed to evaluate whether postoperative adjuvant radiotherapy can improve survival and decrease recurrence as compared with surgery alone in resected esophageal cancer. Materials and Methods : From Jan. 1985 to Dec. 1993, among 94 esophageal cancer Patients treated with surgery, fifty-one patients were included in this study. Transthoracic esophagectomy was peformed in 35 patients and transhiatal esophagectomy in 16. Postoperative adjuvant radiotherapy was peformed 4 weeks after surgery in 26 among 38 patients in stage II and III. A total dose of $30\~60\;Gy$ in 1.8 Gy daily fraction, median 54 Gy over 6 weeks, was delivered in the mediastinum+both supraclavicular lymph nodes or celiac lymph nodes according to the tumor location. Forty-seven patients$(92\%)$ had squamous histology. The median follow-up period was 38 months. Results : The overall 2-year and 5-year survival and median survival were $56.4\%,\;36.8\%$ and 45 months. Two-year and 5-year survival and median survival by stage were $92\%,\;60.3\%$ for stage I, $63\%,\;42\%$ and 51 months for stage II and $34\%,\;23\%$ and 19 months for stage III (p=0.04). For stage II and III patients, 5-year survival and median survival were $22.8\%$, 45 months for the surgery alone group and $37.8\%$, 22 months for the postoperative RT group (p=0.89). For stage III patients, 2-year survival and median survival were $0\%$, 11 months for the surgery alone group and $36.5\%$, 20 months for the postoperative RT group (p=0.14). Local and distant failure rates for stage II and III were $50\%,\;16\%$ for the surgery alone and $39\%,\;31\%$ for the postoperative RT group. For N1 patients, local failure rate was $71\%$ for the surgery alone group and $37\%$ for the postoperative RT group (p=0.19). Among 10 local failures in the postoperative RT group, in-field failures were 2, marginal failures 1, out-field 5 and anastomotic site failures 2. Conclusion : There were no statistically significant differences in either the overall survival or the patterns of failure between the surgery alone group and the postoperative RT group for resected stage II and III esophageal cancer. But this study showed a tendency of survival improvement and decrease in local failure when postoperative RT was peformed for stage III or N1 though statistically not significant. To decrease local failure, a more generous radiation field encompassing the supraclavicular, mediastinal, and celiac lymph nodes and anastomotic site in postoperative adjuvant treatment should be considered.