Co-authorship patterns and networks of Korean radiation oncologists

Choi, Jin-Hyun,Kang, Jin-Oh,Park, Seo-Hyun,Kim, Sang-Ki The Korean Society for Radiation Oncology 2011 Radiation Oncology Journal Vol.29 No.3

Purpose: This research aimed to analyze the patterns of co-authorship network among the Korean radiation oncologists and to identify attributing factors for the formation of networks. Materials and Methods: A total of 1,447 articles including contents of ‘Radiation Oncology' and 'Therapeutic Radiology' were searched from the KoreaMed database. The co-authorship was assorted by the author's full name, affiliation and specialties. UCINET 6.0 was used to fi gure out the author's network centrality and the cluster analysis, and KeyPlayer 1.44 program was used to get a result of key player index. Sociogram was analyzed with the Netdraw 2.090. The statistical comparison was performed by a t-test and ANOVA using SPSS 16.0 with p-value < 0.05 as the significant value. Results: The number of articles written by a radiation oncologist as the first author was 1,025 out of 1,447. The pattern of coauthorship was classified into five groups. For articles of which the first author was a radiation oncologist, the number of singleauthor articles (type-A) was 81; single-institution articles (type-B) was 687; and multiple-author articles (type-C) was 257. For the articles which radiation oncologists participated in as a co-author, the number of single-institution articles (type-D) was 280 while multiple-institution articles (type-E) were 142. There were 8,895 authors from 1,366 co-authored articles, thus the average number of authors per article was 6.51. It was 5.73 for type-B, 6.44 for type-C, 7.90 for type-D, and 7.67 for type-E (p = 0.000) in the average number of authors per article. The number of authors for articles from the hospitals published more than 100 articles was 7.23 while form others was 5.94 (p = 0.005). Its number was 5.94 and 7.16 for the articles published before and after 2001 (p = 0.000). The articles written by a radiation oncologist as the first author had 5.92 authors while others for 7.82 (p = 0.025). Its number was 5.57 and 7.71 for the Journal of the Korean Society for Therapeutic Radiology and Oncology and others (p = 0.000), respectively. Among the analysis, a significant difference in the average number of author per article was indicated. The out-degree centrality of network among authors was 4.26% (2.03-7.09%) while in-degree centrality was 1.31% (0.53-2.84%). The three significant nodes were classified and listed as following: Choi, Eun Kyung for 1991-1995, Kim, Dae Young for 1998-2001, Park, Won and Lee, Sang Wook for 2003-2010. Choi, Eun Kyung and Kim, Dae Young appeared in two cases, and ranked as the highest degree in centrality. In the key player analysis, Choi, Eun Kyung and Lee, Sang Wook appeared in two cases, and ranked as the highest. From the cluster analysis, Sungkyunkwan University, Seoul National University and Yonsei University revealed as the three large clusters when Ulsan University, Chonnam National University, and Korea Institute of Radiological & Medical Science as the medium clusters. Conclusion: The Korean radiation oncologist's society shows a closed network with numerous relationships among the particular clusters, and the result indicates it is different from other institutions in the pattern of co-authorship formation of the major hospitals.

Development of new on-line statistical program for the Korean Society for Radiation Oncology

Song, Si Yeol,Ahn, Seung Do,Chung, Weon Kuu,Shin, Kyung Hwan,Choi, Eun Kyung,Cho, Kwan Ho The Korean Society for Radiation Oncology 2015 Radiation Oncology Journal Vol.33 No.2

Purpose: To develop new on-line statistical program for the Korean Society for Radiation Oncology (KOSRO) to collect and extract medical data in radiation oncology more efficiently. Materials and Methods: The statistical program is a web-based program. The directory was placed in a sub-folder of the homepage of KOSRO and its web address is http://www.kosro.or.kr/asda. The operating systems server is Linux and the webserver is the Apache HTTP server. For database (DB) server, MySQL is adopted and dedicated scripting language is the PHP. Each ID and password are controlled independently and all screen pages for data input or analysis are made to be friendly to users. Scroll-down menu is actively used for the convenience of user and the consistence of data analysis. Results: Year of data is one of top categories and main topics include human resource, equipment, clinical statistics, specialized treatment and research achievement. Each topic or category has several subcategorized topics. Real-time on-line report of analysis is produced immediately after entering each data and the administrator is able to monitor status of data input of each hospital. Backup of data as spread sheets can be accessed by the administrator and be used for academic works by any members of the KOSRO. Conclusion: The new on-line statistical program was developed to collect data from nationwide departments of radiation oncology. Intuitive screen and consistent input structure are expected to promote entering data of member hospitals and annual statistics should be a cornerstone of advance in radiation oncology.

Mechanisms of radiation-induced normal tissue toxicity and implications for future clinical trials

Kim, Jae Ho,Jenrow, Kenneth A.,Brown, Stephen L. The Korean Society for Radiation Oncology 2014 Radiation Oncology Journal Vol.32 No.3

To summarize current knowledge regarding mechanisms of radiation-induced normal tissue injury and medical countermeasures available to reduce its severity. Advances in radiation delivery using megavoltage and intensity-modulated radiation therapy have permitted delivery of higher doses of radiation to well-defined tumor target tissues. Injury to critical normal tissues and organs, however, poses substantial risks in the curative treatment of cancers, especially when radiation is administered in combination with chemotherapy. The principal pathogenesis is initiated by depletion of tissue stem cells and progenitor cells and damage to vascular endothelial microvessels. Emerging concepts of radiation-induced normal tissue toxicity suggest that the recovery and repopulation of stromal stem cells remain chronically impaired by long-lived free radicals, reactive oxygen species, and pro-inflammatory cytokines/chemokines resulting in progressive damage after radiation exposure. Better understanding the mechanisms mediating interactions among excessive generation of reactive oxygen species, production of pro-inflammatory cytokines and activated macrophages, and role of bone marrow-derived progenitor and stem cells may provide novel insight on the pathogenesis of radiation-induced injury of tissues. Further understanding the molecular signaling pathways of cytokines and chemokines would reveal novel targets for protecting or mitigating radiation injury of tissues and organs.

Radioprotective effect of mefenamic acid against radiation-induced genotoxicity in human lymphocytes

Hosseinimehr, Seyed Jalal,Nobakht, Reyhaneh,Ghasemi, Arash,Pourfallah, Tayyeb Allahverdi The Korean Society for Radiation Oncology 2015 Radiation Oncology Journal Vol.33 No.3

Purpose: Mefenamic acid (MEF) as a non-steroidal anti-inflammatory drug is used as a medication for relieving of pain and inflammation. Radiation-induced inflammation process is involved in DNA damage and cell death. In this study, the radioprotective effect of MEF was investigated against genotoxicity induced by ionizing radiation in human blood lymphocytes. Materials and Methods: Peripheral blood samples were collected from human volunteers and incubated with MEF at different concentrations (5, 10, 50, or $100{\mu}M$) for two hours. The whole blood was exposed to ionizing radiation at a dose 1.5 Gy. Lymphocytes were cultured with mitogenic stimulation to determine the micronuclei in cytokinesis blocked binucleated lymphocyte. Results: A significant decreasing in the frequency of micronuclei was observed in human lymphocytes irradiated with MEF as compared to irradiated lymphocytes without MEF. The maximum decreasing in frequency of micronuclei was observed at $100{\mu}M$ of MEF (38% decrease), providing maximal protection against ionizing radiation. Conclusion: The radioprotective effect of MEF is probably related to anti-inflammatory property of MEF on human lymphocytes.

Delayed radiation-induced inflammation accompanying a marked carbohydrate antigen 19-9 elevation in a patient with resected pancreatic cancer

Mattes, Malcolm D.,Cardinal, Jon S.,Jacobson, Geraldine M. The Korean Society for Radiation Oncology 2016 Radiation Oncology Journal Vol.34 No.2

Although carbohydrate antigen (CA) 19-9 is a useful tumor marker for pancreatic cancer, it can also become elevated from a variety of benign and malignant conditions. Herein we describe an unusual presentation of elevated CA 19-9 in an asymptomatic patient who had previously undergone adjuvant chemotherapy and radiation therapy for resected early stage pancreatic cancer. The rise in CA 19-9 might be due to delayed radiation-induced inflammation related to previous intra-abdominal radiation therapy with or without radiation recall induced by gemcitabine. After treatment with corticosteroids the CA 19-9 level decreased to normal, and the patient has not developed any evidence of recurrent cancer to date.

Radioprotective Effect of Mesna on Mouse Testis

류삼열,김재철,김상보,박인규,Ryu Samuel,Kim Jaw Cheol,Kim Sang Bo,Park In Kyu The Korean Society for Radiation Oncology 1990 Radiation Oncology Journal Vol.8 No.2

고환암에서 mesna는 ifosfamide와 병용 투여하면 요관 계통의 부작용을 방지할 수 있으며, adriamycin과 같이 사용하는 경우 항암제의 세포증식 억제능을 감소시키지 않으면서 부작용을 경감 시킨다. 방사선 보호제의 sulfhydryl가 방사선에 의하여 발생하는 hydroxyl 유리기와 반응하여 조직을 보호할 수 있고, 역시 체내에서 유리기를 발생하는 adriamycin의 독작용을 musua가 감소시키는 사실에 근거하여, 쥐에 mesna와 방사선을 투여하여 mesna의 방사선보호 작용을 관찰하였다. 본 연구에서는 방사선 단독 처치군과 mesna와 방사선 처치군에서 고환의 수정관 내의 배아세포의 수와 형태적 변화를 현미경 하에서 매주 비교하고 재생 능력의 차이를 확인하였다. 양쪽 군에서 공히 초기에 세포 수가 감소하고 후기에 다시 세포가 증식 하였으며, 가장 세포 수가 적게 관찰된 시기는 방사선 조사 후 3주 째였다. 모든 관찰 기간에서 mesna 처치군의 평균 배아 세포수가 방사선 단독 처치군보다 통계적으로 유의하게 많이 관찰되었고(p<0.05), 또한 mesna 처치군에서 더 유효한 세포 재생 능력이 있음이 관찰되었다. 이는 mesna가 방사선 상해로부터 고환의 수정관 내 배아세포를 보호하고 있음을 입증하는 것으로 사료된다. Mesna가 고환 이외의 다른 조직을 방사선으로부터 보호할 수 있는지의 여부와 종양의 관해율을 저해하지 않을지에 대하여는 더 이상의 연구가 필요할 것으로 생각된다. Mesna has been used with ifosfamide to prevent urotoxicity in the treatment of testicular cancers. This drug also protected the toxicities of adriamycin without compromising cytostatic activity. With an idea of radioprotective role of sulfhydryl group of radioprotectors and of mesna decreasing the toxic effect of adriamycin which produces free radicals, mesna and radiation were administered to mice to study the protective effect of this drug and to identify the difference in regenerative capacity of the germ cells in the testis between radiation-treated and both mesna-and radiation-treated groups. The shape and numbers of spermatogenic cells in the seminiferous tubules were examined every week after irradiation. In both groups, initial reduction and later recovery in germ cell numbers and shape was observed. The lowest germ cell number was found around three weeks after irradiation. Mean germ cell number of the mesna-treated group was significantly higher than radiation-treated group at all observed periods (p<0.05). More competent regeneration was present in mesna-treated group. These results suggest that mesna protect the testis from radiation injury. Further study will be necessary to identify whether mesna protects other tissues from radiation and it does not hamper tumor control.

The safety and efficacy of EGF-based cream for the prevention of radiotherapy-induced skin injury: results from a multicenter observational study

Kang, Hyun-Cheol,Ahn, Seung-Do,Choi, Doo-Ho,Kang, Min Kyu,Chung, Woong-Ki,Wu, Hong-Gyun The Korean Society for Radiation Oncology 2014 Radiation Oncology Journal Vol.32 No.3

Purpose: This study was designed to evaluate the efficacy and safety of topically applied recombinant human epidermal growth factor (rhEGF) for the prevention of radiation-induced dermatitis in cancer patients. Materials and Methods: From December 2010 to April 2012, a total of 1,172 cancer patients who received radiotherapy (RT) of more than 50 Gy were prospectively enrolled and treated with EGF-based cream. An acute skin reaction classified according to the Radiation Therapy Oncology Group 6-point rating scale was the primary end point and we also assessed the occurrence of edema, dry skin, or pruritus. Results: The percentage of radiation dermatitis with maximum grade 0 and grade 1 was 19% and 58% at the time of 50 Gy, and it became 29% and 47% after completion of planned RT. This increment was observed only in breast cancer patients (from 18%/62% to 32%/49%). Adverse events related to the EGF-based cream developed in 49 patients (4%) with mild erythema the most common. Skin toxicity grade >2 was observed in 5% of the patients. Edema, dry skin, and pruritus grade ${\geq}3$ developed in 9%, 9%, and 1% of the patients, respectively. Conclusion: Prophylactic use of an EGF-based cream is effective in preventing radiation dermatitis with tolerable toxicity. Further studies comparing EGF cream with other topical agents may be necessary.

Experimental Computer-Based Management System of Patients in Radiation Oncology

최일봉,김춘열,박용휘,Choi, Ihl-Bohng,Kim, Choon-Yul,Bahk, Yong-Whee The Korean Society for Radiation Oncology 1987 Radiation Oncology Journal Vol.5 No.2

근래에 와서 치료방사선학 영역에서의 전산화가 급속히 이루어지고 있으나 그 전산화의 대부분은 치료계획용 계산에 치우쳐져 있고 환자정보관리, 퇴원환자의 추적검사, 환자관리사무에 있어서의 전산화에 필요한 프로그램 등 환자관리에 필요한 프로그램은 매우 적으며, 상업적으로 개발된 프로그램은 일반화하기에는 많은 문제점을 갖고 있다. 이에 저자들은 16비트 개인용 컴퓨터를 이용하여 환자 현황 관리 프로그램을 시험 제작하였다. 1. 환자정보의 입력은 특별한 부호나 숫자를 사용하지 많고 현재 우리가 사용하는 영어나 한글을 그대로 쓸 수 있었다. 2 환자정보의 분석은 간단한 명령이나 키 동작으로 이루어질 수 있으며 특히 환자 현황에 대한 도표를 즉시 묘출할 수 있었다. 3. 환자관리정보의 내용은 기존 프린터를 이용하여 쉽게 문서화할 수 있으며, 학술발표, 강의재료 및 교육자료로 사용할 수 있었다. Currently, many computer systems are used in many areas of medicine including radiation oncology. For the most part, the computer system has proved to be useful in radiotherapeutic planning and dose calculation. There has been attempts to develop computer system including information management of patients, patient tracing, and office automation in radiation oncology department. But some of these available commercial systems have shortcomings. We developed a management system of patients in our radiation oncology department that integrated most of items for the evaluation of patents. In particular, the data were stored in a natural language (noncoded) and made themselves easily understandable by all clinical groups. In addition , the data could be isolated in files from which the computer could generate graphs and static data by the use of some simple commands. The system provided us with not only the functions of case review but functions of preparation of conferences, lectures and resident teaching.

Breast Conserving Operation and Radiation Therapy in Early Breast Cancer : Interim Analysis

김진희,김옥배,김유사,Kim, Jin-Hee,Kim, Ok-Bae,Kim, You-Sah The Korean Society for Radiation Oncology 2001 Radiation Oncology Journal Vol.19 No.1

목적 : 초기 유방암 (병기 I, II)에서는 유방 보존 수술과 방사선치료가 선호 받고 있는 치료법이다. 본원에서는 1992년부터 이러한 방법을 시행 중이며 실패양상과 미용효과 및 생존률을 알아보고자 하였다. 대상 및 방법 : 1992년 1월부터 1997년 12월까지 계명대학교 동산의료원에서 유방 보존 수술과 방사선치료를 받은 초기 유방암환자 72명을 대상으로 하였다. 연령분포는 $25\~77$세(중앙값 43세)이었고 TNM 병기는 0기 5명, I기 33명, IIa기 25명, IIb기 9명이었다. 모든 환자는 유방의 부분절제술과 동측 액와림프절 곽청술을 시행하고 방사선치료를 하였다. 유방의 방사선치료는 동측 전체 유방에 6 MV 광자선으로 $50\~54\;Gy$를 5주에서 6주간에 조사하였고 원발병소에 추가 방사선은 전자선으로 $10\~16\;Gy$를 1주에서 2주간 조사하였다. 항암화학요법은 41명에서 방사선치료 전후에 시행하였다. 미용효과는 환자의 만족도를 매우좋음, 좋음, 만족할만함, 불만족의 4단계로 설문조사를 시행하였다. 추적관찰기간은 22개월에서 91개월로 중앙값이 40개월이었다. 결과 : 전체환자의 5년 무병생존률은 $95.8\%$ 이었다. 병기별로는 0기에는 $100\%$, I기에는 $96.9\%$, IIa기에는 $96\%$, IIb기에는 $88.9\%$이었다. 2명에서 원격전이가 있었으며 1명에서 동시재발이 있었다. 원격전이 환자 중 1명에서는 방사선 치료 후 14개월에 골, 간에 있었고 1명에서는 21개월에 폐와 양측 쇄골상 림프절에 전이되었다. 동시재발환자는 14개월에 동측 유방의 다른 사분역에 재발하여 유방전절제술과 항암화학요법을 시행하고 44개월에 뇌전이로 방사선치료와 항암화학요법을 시행하였으나 55개월 째 사망하였다. 부작용으로는 4명에서 무증상의 폐렴양 음영이 흉부 X선 촬영에서 보였고 1명에서 증상을 동반한 방사선폐렴이 있었고 4명$(5\%)$에서 경미한 정도의 손부종이나 팔 부종이 있었다. 미용결과는 설문에 응답한 59명중 51명$(86\%)$에서 좋음에서 매우 좋음으로 나타났다. 결론 : 이상의 결과로 초기 유방암에서 유방보존수술과 방사선치료는 안전한 치료방법이며 우수한 생존률과 미용 결과를 보인다고 생각되며 향후 장기추적관찰을 통해 예후 인자의 분석이 필요 할 것으로 사료된다. Purpose : To evaluate interim results in terms of failure, cosmetic results and survival after breast conserving operation and radiation therapy in early breast cancer. Material and Methods : From January 1992 through December 1997, seventy two patients with early stage 0, I and II breast cancer were treated with conservative surgery plus radiotherapy at Keimyung University Dongsan Medical Center. Age distribution was 25 to 77 years old with median age of 43. According to TNM stage, five patients had stage 0, thirty three were stage I, twenty five were IIa, and nine were IIb. Most patients underwent excision of all gross tumor and ipsilateral axillary dissection. Breast was irradiated through medial and lateral tangential fields of 6 MV photons to 50.4 Gy in 28 fractions over 5.5 weeks. We delivered a boost irradiation dose of 10 to 16 Gy in 1 to 2 weeks to excision site. Adjuvant chemotherapy was administered in forty one patients with CMF (cyclophosphamide, methotrexate, 5-fluorouracil) regimens of 6 cycles concurrently or before radiation. Cosmetic results were assessed by questionnaire to patients grading of excellent, good, fair, poor. Follow-up periods were 22 to 91 months with median 40 months. Results : Five year disease free survival rate (5YDFS) was $95.8\%$. According to stage, 5YDFS was $100\%,\;96.9\%,\;96\%\;and\;88.9\%$ in stage 0, I, IIa and IIb, respectively. Two patients had distant metastasis and one had local and distant failure. One patient with distant failure had bone and liver metastasis at 14 months after treatment and the other had lung and both supraclavicular metastasis at 21 months after treatment. Patient with local and distant failure had local recurrence on other quadrant in same breast and then salvaged with total mastectomy and chemotherapy but she died due to brain metastasis at 55 months. Complications were radiation pneumonitis in five patients (four patients of asymptomatic, one patients of symptomatic) and hand or arm edema(4 patients). Fifty nine patients answered our cosmetic result questionnaire and cosmetic results were good to excellent in fifty one patients $(86\%)$. Conclusion : We considered that conservative surgery and radiation for the treatment of early stage invasive breast cancer was safe and had excellent survival and cosmetic results. We need to assess about prognostic factors with longer follow up and with large number of patients.

The protective effects of trace elements against side effects induced by ionizing radiation

Hosseinimehr, Seyed Jalal The Korean Society for Radiation Oncology 2015 Radiation Oncology Journal Vol.33 No.2

Trace elements play crucial role in the maintenance of genome stability in the cells. Many endogenous defense enzymes are containing trace elements such as superoxide dismutase and metalloproteins. These enzymes are contributing in the detoxification of reactive oxidative species (ROS) induced by ionizing radiation in the cells. Zinc, copper, manganese, and selenium are main trace elements that have protective roles against radiation-induced DNA damages. Trace elements in the free salt forms have protective effect against cell toxicity induced by oxidative stress, metal-complex are more active in the attenuation of ROS particularly through superoxide dismutase mimetic activity. Manganese-complexes in protection of normal cell against radiation without any protective effect on cancer cells are more interesting compounds in this topic. The aim of this paper to review the role of trace elements in protection cells against genotoxicity and side effects induced by ionizing radiation.