Korean Journal of Clinical Oncology 2014;10:73-77 http://dx.doi.org/10.14216/kjco.14014 pissn 1738-8082 eissn 2288-4084 Original Article 북한이탈주민에서발생한암의임상병리적특징 박재민 1, 김은영 1, 정일용 1, 박세혁 1, 박종민 1, 윤여규 1, 오흥권 2, 김중석 3, 주성홍 4 1 국립중앙의료원외과, 2 서울대분당병원외과, 3 국립중앙의료원외상외과, 4 국립중앙의료원산부인과 Clinicopathologic characteristics of cancer of North Korean defectors Jae Min Park 1, Eunyoung Kim 1, Il Yong Chung 1, Sei-Hyeog Park 1, Jong-Min Park 1, Yeo-Kyu Youn 1, Heung-Kwon Oh 2, Joong-Suck Kim 3, Sung-Hong Joo 4 1 Department of Surgery, National Medical Center, Seoul; 2 Department of Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam; Departments of 3 Trauma Surgery and 4 Obstetrics and Gynecology, National Medical Center, Seoul, Korea Purpose: In this study, we compared characteristics of cancer of North Korean defectors to South Korean. In order to clarify the clinicopathologic characteristics of cancer in North Korean defectors. Methods: This study is a retrospective study through chart review of patients diagnosed as cancer at National Medical Center from 2008 to 2013. Control group included South Korean cancer patients who were diagnosed as cervical cancer, thyroid cancer, liver cancer, stomach cancer at same hospital during same period. Two groups were analyzed and compared by sex, age, past medical history, cancer origin, cancer stage, and treatment. Results: Among 1,760 North Korean defector patient registered in National Medical Center, 61 patients were diagnosed as cancer, which was 3.5%. Cervical cancer (19.7%), thyroid cancer (19.7%), liver cancer (14.1%) and stomach cancer (10.3%) were 4 most frequent cancer. In South Korean cancer patient, percentage was as follows: thyroid cancer (33.7%), stomach cancer (7.8%), liver cancer (7.3%), cervical cancer (3.7%). Conclusion: Cancers closely related to socio-economic status, such as cervical cancer and hepatitis-b related liver cancer, were relatively more frequent in North Korean defectors than South Koreans. As for cancers in which early diagnosis is important such as thyroid cancer and stomach cancer, there were no significant differences in age-prevalence, disease course and treatment. Keywords: Clinicopathologic characteristics, North Korean defector, Comparison, Socio-economic status 서론 1970 년대초반이후북한의보건의료시스템은점차쇠퇴해갔다. 북한은구소련과동구권의잇단붕괴와김일상사망후 2 대세습체제유지및국내외정치적환경변화, 수차례지속된자연재해, 안보문제등이원인이되어극심한경제난에시달리게되었다 [1]. 이렇게 Received: Aug 20, 2014 Accepted: Nov 5, 2014 Correspondence to: Il Yong Chung Department of Surgery, National Medical Center, 245 Euljiro, Jung-gu, Seoul 100-799, Korea Tel: +82-2-2260-7164, Fax: +82-2-2267-8685 E-mail: doorkeeper1@gmail.com Copyright Korean Society of Clinical Oncology This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. 보건의료의하부시스템이악화되자, 1980 년대까지이룩했던보건의료시스템및기대여명연장등의보건의료성과들도무너졌다. 이에따라북한주민들의건강상태는전반적으로열악해졌다 [1,2]. 식량안보뿐만이아니라, 높은영아사망률과모성사망률, 낮은기대여명, 영양실조및감염병의빈발등국제보고서의수치가이를반증한다 [2]. 북한이탈주민의국내입국규모는 1998 년이후매년꾸준히증가하고있다. 2007 년 2 월북한이탈주민총입국자수가 1 만명을넘어섰고, 2010 년 12 월말까지총 20,399 명의북한이탈주민이국내에입국하였다 [3]. 성별입국비율을살펴보면여성의입국비율은 2002 년을기점으로남성을추월하여 2009 년도에는약 77% 를차지하고있다 [3]. 2006 년질병관리본부에서시행한북한이탈주민을대상으로한건강검진상면역도, 감염률, 미충족의료수요율 (medical unmet needs) 에서남북간에큰차이를보이는것으로나타났으며이는통일후발생할의료수요에대한예측이필요함을의미한다 [4]. www.kjco.org 73
남한과북한은같은민족으로같은유전자를공유하지만환경의영향에따른암발병을무시할수는없다 [5]. 다른환경에서거주하며같은유전자를공유하는한민족의암발생을조사함에있어북한이탈주민에대한연구는기본적인예측자료로활용할수있음이예상된다. 일례로미국등선진국의경우난민에대한질병감시체계가이루어져있어발생가능한질환에대처하기위한자료로사용하고있다 [6]. 둘째로남북한사회와의료를비교연구하는데있어암발병현황자료의가치또한의료복지지표로서기능할수있다 [7]. 통계치산출방식의차이와자료의신뢰성에대한의문때문에북한에서발표된의료지표의통계치만으로북한사회상과의료의질에있어서의변화를이해하는것은극도로어렵다. 물론북한인구전체를모집단으로한암발병자료도현재로서는확보할수없는상태이다. 단지남한으로입국하는북한이탈주민은 70 대부터어린이에이르기까지모든연령대와성별을망라하고있어서이들의암유병현황을조사하여이를이들의사회경제적배경정보와함께해석하면 1930 년대이후에출생한북한인구집단의암환자의특성을유추할수있을것으로기대된다 [8,9]. No. of patient 600 500 400 300 200 100 0 19 20 29 30 39 40 49 50 59 60 69 70 Age (yr) Male Female Fig. 1. Age distribution of North Korean defector patients registered at National Medical Center. 본연구에서는북한이탈주민과남한의암환자들의암특성을비교하여북한이탈주민에서발생하는암의임상병리학적특성을밝히고자하였다 [10]. 방법 국립중앙의료원은북한이탈주민에대한진료비지원을하고있어서울, 경기지역의북한이탈주민이가장많이등록되어있다. 2008 년 1 월부터 2013 년 12 월까지국립중앙의료원에등록된 1,760 명의북한이탈주민중에암진단을받은 61 명의환자들을연구군으로선정하여그들의성별, 나이, 과거력과암의발병부위와병기를조사했다 (Figs. 1, 2). 같은기간에국립중앙의료원에서환자들중외국인및북한이탈주민을제외한대한민국국적의암환자를대상으로성별, 나이, 과거력과암의발병부위와병기를조사하였다. 이중북한이탈주민에서가장흔한암종 4 개에해당하는갑상선암, 자궁경부암, 위암, 간암환자를대조군으로선정하였다. 과거력은고혈압, 당뇨, 간염, 결핵의병력에대해서조사하였다. 고혈압과당뇨의경우진단후약물복용력이있는환자들을포함하였고, 간염의경우혈액검사상보균자또는급. 만성간염이확진된환자들을포함시켰다. 결핵의경우과거력상결핵진단후약물복용한과거력이있는환자및현재치료중인환자들을포함하였다. 병기는미국의국가암연구센터에서개발한 Surveillance, Epidemiology, and End Results 프로그램에서사용중인국한 / 국소진행 / 원격전이요약병기를사용하였다 [11]. 치료에있어서는수술, 항암치료, 방사선치료, 보존적치료의 4 그룹으로나누어졌다. 수술은원발부위혹은전이병소에대한고식적수술및근치적수술을모두포함하였다. 항암치료의경우정맥내주사, 경구항암제등전통적항암요법과항암제를이용한화학색전술을포함하였다. 방사선치료의경우외부방사선치료및근접치료를모두포함하였다. 두그룹간에환자수의규모가차이가심하여발생분율을계산하여두그룹간의암발생분포를비교하고자하였다. 통계분석은 IBM SPSS ver. 20 (IBM Co., Armonk, NY, USA) 을사용하여이루어졌다. 단일인자분 Male Female Brain cancer 2 (8%) Lung cancer 5 (22%) Etc. 3 (13%) Liver cancer 8 (35%) Stomach cancer 5 (22%) Breast cancer Brain cancer Stomach cancer Liver cancer Etc. 6 (16%) Thyroid cancer 12 (32%) Cervical cancer 12 (32%) A B Fig. 2. Cancer distribution of North Korean defectors patients registered at National Medical Center. (A) Male. (B) Female. 74 Korean Journal of Clinical Oncology
Jae Min Park et al. Cancers in North korean defectors, as reflextion of cancers in North Korea 석에있어서, 범주형자료는카이제곱과피셔테스트로, 연속형자료는 t-test 로검정하였다. 0.05 이하의 P 값은통계적으로유의한것으로판단하였다. 결과 북한이탈주민환자 1,760 명중해당기간에암으로진단된환자수는모두 61 명으로전체환자중 3.5% 가암환자였다. 남자가 23 명, 여자 Table 1. Characteristics of North Korean defector cancer patients Characteristic Male Female Patients (n) 23 38 Age (yr, range) 54.3± 12.3 (45 75) 55.1± 12.4 (29 80) Past medical history Hepatitis 7 (70.0) 5 (33.3) HTN 2 (20.0) 5 (33.3) Tb 1 (10.0) 4 (26.7) DM 0 (0) 1 (6.7) Values are presented as mean± standard deviation or number (%). HTN, hypertension; Tb, tuberculosis; DM, diabetes mellitus. Table 2. Characteristics of South Korean cancer patients Characteristic Male Female Patients (n) 1,530 1,521 Cancer Thyroid cancer 219 (14.3) 809 (53.2) Stomach cancer 162 (10.6) 78 (5.1) Liver cancer 164 (10.7) 58 (3.8) Cervical cancer 0 (0) 114 (7.5) Values are presented as number (%). 가 38 명으로성비는 1:1.65 였다. 평균나이는남성이 54.3 ± 12.3 세, 여성이 55.1 ± 12.4 세로나타났다 (Table 1). 대조군은전체암환자수가 3,051 명이었고남자환자가 1,530 명여자환자가 1,531 명으로성비는 1:1 이었다 (Table 2). 장기별암발생분율을대조군과비교해본결과연구군에서는자궁경부암이 19.7% 로가장많았다. 여성으로한정하였을때연구군의경우에자궁경부암환자가 31.6% 로나타났으며, 대조군에서는 7.5% 로나타나연구군의경우에높게나타났다. 연령의경우에연구군이 51.6 세, 대조군의경우는 44.8 세로나타났다. 병기의경우에는연구군에서국소전이, 원격전이가대조군보다높게나타났으나유의한차이를보이지는않았다 (Table 3). 갑상선암은연구군의 19.7% 에서발생하여자궁경부암과함께가장많이발생한암이었다. 두군간에진단당시의평균연령, 종양크기및병기의유의한차이는없었다 (Table 4). 연구군의간암발생분율이 16.3% 를차지하고있었다. 남녀비율은 4:1 로남자환자가많았다. 대조군에서는 7.5% 의발병분율을보여연구군에서보다높은발병분율을보였다. 발병연령의경우에연구군에서낮게나타났으며원격전이가유의하게높은것으로나타났 Table 3. Characteristics of cervical cancer patients registered at National Medical Center (foreigners excluded) n (%) 12/38 (31.6) 114/1,521 (7.5) Age (yr, range) 51.6± 9.98 (36 68) 44.8± 10.5 (25 83) 0.035 Stage 0.623 Localized 8 (66.7) 87 (79) Regional 3 (25.0) 18 (15.8) Distant 1 (8.3) 9 (5.2) Table 4. Characteristics of thyroid cancer patients registered at National Medical Center (foreigners excluded) n (%) 12 (16.4) 1,028 (33.7) 0.036 Age (yr, range) 47.7± 12.9 (29 71) 47.6± 9.96 (17 78) 0.514 Female (%) 12 (100) 809 (78.7) 0.072 Size of tumor (cm, range) 0.9± 0.37 (0.3 1.5) 0.94± 0.40 (0.1 5.0) 0.132 Pathology (%) 1.487 Papillary thyroid carcinoma 12 (100) 1,011 (98.3) Follicular thyroid carcinoma 0 (0) 14 (1.4) Medullary thyroid carcinoma 0 (0) 3 (0.3) Papillary thyroid carcinoma No. of papillary thyroid micro carcinoma (%) 7/12 (58.3) 633/1,011 (62.6) 0.311 No. of overt papillary thyroid carcinoma (%) 5/12 (41.7) 378/1,011 (37.4) 0.152 Stage 0.214 Localized 8 (66.7) 698 (67.9) Regional 4 (33.3) 325 (31.5) Distant 0 (0) 5 (0.5) www.kjco.org 75
Table 5. Characteristics of liver cancer patients registered at National Medical Center (foreigners excluded) n (%) 10 (14.1) 222 (7.3) 0.024 Age (yr, range) 50.9± 8.10 (44 69) 59.31± 14.04 (27 91) 0.015 Stage 0.003 Localized 3 (30.0) 175 (63.8) Regional 2 (20.0) 42 (27.6) Distant 5 (50.0) 5 (8.6) HBV (+) 9 (90) 100 (45) < 0.0001 HBV, hepatitis B virus. 다. 연구군에서 B 형간염환자및보균자의빈도가대조군에비해유의하게높은양상을보였다 (Table 5). 위암이 11.5% 로 4 위를차지하고있었다. 남녀비율은 5:2 로남자환자가많았다. 연구군의남녀비를고려할때남자들에서비교적많이발생하는것으로나타났다. 대조군에서는 7.8% 의발병분율을보였고두그룹간에발생빈도, 발생연령에서유의미한차이를보이지않았다. 병기에서는연구군이대조군에비해조기위암이많은것으로나타났다 (Table 6). 고찰 연구군에서는자궁경부암이 19.7% 로가장많았다. 여성으로한정하여보면전체여성암환자의 31.5% 가자궁경부암환자였다. 이는대조군의여성암환자중자궁경부암이차지하는비율이 7.5% 임을감안할때상대적으로높은비율이었다. 연구군의연령이대조군에비해고령인경향을보였다. 자궁경부암은해당지역의사회경제적수준과밀접한연관이있는질환이다. 자궁경부암의선별검사가이루어지기위해서는의료접근성, 경제수준, 인구구성및교육수준을포함한사회경제적수준이중요한요인이되기때문이다 [12,13]. 그렇기때문에북한에서새로이유입되는북한이탈주민의입국시자궁경부암에대한선별검사가철저히이루어져야하며향후 20 30 대의젊은세대의북한이탈주민에서의자궁경부암의발병추이를관찰하여비교하는것이필요할것으로보인다. 갑상선암이 19.7% 로공동으로가장많았다. 대조군의암환자중갑상선암이차지하는비율은 33.7% 이지만본기관에서갑상선외과진료가시작된 2012 년 1 월부터 2013 년 12 월에진단된환자가 940 명으로전체대조군의 91.4% 를차지하여, 타병원에서갑상선암진단후수술을위해본원을방문하는환자수의급증이선택성편향으로작용하였다. 반면에연구군은 2008 년부터 2011 년까지진단된환자가 5 명 (41.7%), 2012 년부터 2013 년까지진단된환자가 7 명 (58.3%) 로진료시기에따른편향은없었다. 두군간의갑상선암의진단시평균나이, 평균종양크기, 병리, 병기의차이는없었다. 또한전체갑상선유두암환자중갑상선미세유두암 (size 1 cm) 비율은연구군이 58.3%, 대조군에서 52% 로유의한차이를보이지않았다 Table 6. Characteristics of stomach cancer patients registered at National Medical Center (foreigners excluded) n (%) 7 (10.3) 239 (7.8) 0.399 Age (yr, range) 61.42± 11.01 (44 75) 62.05± 12.37 (28 88) 0.908 Stage 0.128 Localized 6 (85.7) 104 (43.5) Regional 1 (14.3) 126 (52.7) Distant 0 (0) 9 (3.8) Values are presented as number (%) or mean± standard deviation. (P = 0.524). 하지만, 북한이탈주민의진단전남한내거주기간과북한이탈시기, 이탈후경로등의조사가불가능하여노출된환경인자의영향등을고려하지못하였기때문에, 연구군과대조군에서발병한갑상선암의임상병리적특징과갑상선미세유두암비율의유사성을북한이탈주민이국내에서받은갑상선암검진의효과라고단정할수없다 [14-16]. 간암의경우 90% 의연구군환자가 B 형간염환자또는보균자였다. C 형간염환자및보균자는없었고 1 명의환자만이 B 형과 D 형간염의동시감염자였다. 그외알코올성간경화등다른원인에의한간암발병환자는 1 명이었다. 대조군에서 B 형간염보균자및환자가 45%, C 형간염환자및보균자가 5%, 동시감염자가 1%, 3% 에서알코올성간경화등다른원인에의한간경화를보인것과다른결과를보였다. C 형간염 ( 보균자포함 ), 알코올성간경화의경우에는유의한차이를보이지않았으나 B 형간염 ( 보균자포함 ) 의경우에는북한이상대적으로남한보다높은비율을보임이유의하게나타났다. 결론적으로연구군의환자들이 B 형간염에대한예방, 진단및치료를대조군에비해잘받지못한것때문으로생각된다. B 형간염자체가사회경제적수준과밀접한연관이있는질환으로인구밀도가높고위생이잘이루어지지않은환경에서잘발병하며사회경제적수준이낮은지역에서는예방접종등이잘이루어지지않아 B 형간염의유병률이높고치료또한잘이루어지지않기때문에간암으로발전하는빈도가높다 [17]. 실제로북한의 B 형간염유병률은 1% 10% 정도로매우높은편이다 [18]. 따라서북한이탈주민의입국시 B 형간염에대한선별검사및치료가필요하다. 또한향후통일이될경우 B 형간염백신등기본예방접종에대한대책을염두에두어야할것이다. 이연구의제한점은연구군에해당되는환자의수가많지않아통계분석이큰의미를주지못했으며환자의예후에대한비교는이루어지지않았다. 단일기관연구이기때문에선택성편향이발생한것을간과할수없다. 또한갑상선암은북한이탈주민의이탈후국내유입까지의기간및경로와국내거주기간을조사할수없어암생물학적차이, 환경적요인의차이, 조기암검진의효과에대한판단은할수없었다. 따라서본연구를바탕으로다수의의료기관이참가하는장기적인연구가필요하다고생각된다. 본연구에서북한이탈주민에서가장빈번히발생한암은자궁경부암, 갑상선암, B 형간염과연관된간암그리고위암이었다. 자궁경 76 Korean Journal of Clinical Oncology
Jae Min Park et al. Cancers in North korean defectors, as reflextion of cancers in North Korea 부암과 B 형간염과연관된간암과같이사회경제적수준과밀접한연관이있는질환의경우, 북한의낮은의료및경제수준을고려할때실제북한에서도유병률이높을것으로예상이된다. 향후통일을준비하면서이와관련하여발생할의료수요에대해적절한의료서비스를제공할수있도록각계각층의다각적인노력이필요할것으로생각된다. CONFLICT OF INTEREST No potential conflict of interest relevant to this article was reported. REFERENCES 1. Lee M, Kim H, Cho D, Kim SY. Overview of healthcare system in North Korea. J Korean Med Assoc 2013;56:358-67. 2. Medical Aid for Childern. Report on pregnancy and labor of North Korean women 2005 [Internet]. Seoul (KR): Healthchild; 2014 [cited 2014 Nov 5]. Available from: http://www.nk health.net/inc/ download.php?code=sub_0305&number=28&filenum=0. 3. Ministry of Unification. Recent status of North Korean defectors [Internet]. Seoul (KR): Statistics Korea; 2014 [cited 2014 Nov 5]. Available from: http:// www.index.go.kr/potal/main/eachdtlpage- Detail.do?idx_cd=1694. 4. Korea Centers for Disease Control and Prevention. Report on health inspection of North Korean defectors. Cheongwon: Korea Centers for Disease Control and Prevention; 2006. 5. National Cancer Institute. Cancer causes and risk factors [Internet]. Bethesda (US): National Cancer Institute; [cited 2014 Jul 4]. Available from: http://www.cancer.gov/cancertopics/causes. 6. Lee D, Philen R, Wang Z, McSpadden P, Posey DL, Ortega LS, et al. Disease surveillance among newly arriving refugees and immigrants Electronic Disease Notification System, United States, 2009. MMWR Surveill Summ 2013;62:1-20. 7. Kelley E, Hurst J. Health Care Quality Indicators Project: Conceptual Framework Paper 23 [Internet]. Paris (FR): Organisation for Economic Co-operation and Development; 2006 [cited 2014 Nov 4]. Available from: http://www.oecd.org/els/health-systems/36262363. pdf. 8. Maheswaran R, Pearson T, Jordan H, Black D. Socioeconomic deprivation, travel distance, location of service, and uptake of breast cancer screening in North Derbyshire, UK. J Epidemiol Community Health 2006;60:208-12. 9. Clegg LX, Reichman ME, Miller BA, Hankey BF, Singh GK, Lin YD, et al. Impact of socioeconomic status on cancer incidence and stage at diagnosis: selected findings from the surveillance, epidemiology, and end results: National Longitudinal Mortality Study. Cancer Causes Control 2009;20:417-35. 10. National Cancer Information Center. National Cancer registeration statistical studies [Internet]. Goyang (KR): National Cancer Information Center; 2014 [cited 2014 Jul 4]. Available from: http://www. cancer.go.kr/mbs/cancer/subview.jsp?id=cancer_060101000000. 11. Surveillance Epidemiology, and End Results Program. Localized/ regional/distant stage adjustments [Internet]. Bethesda (US): National Cancer Institute (US); [cited 2014 Jul 4]. Available from: http://seer.cancer.gov/seerstat/variables/seer/lrd-stage/. 12. Singh GK, Miller BA, Hankey BF, Edwards BK. Persistent area socioeconomic disparities in U.S. incidence of cervical cancer, mortality, stage, and survival, 1975-2000. Cancer 2004;101:1051-7. 13. Baker D, Middleton E. Cervical screening and health inequality in England in the 1990s. J Epidemiol Community Health 2003;57:417-23. 14. Mousavi SM, Brandt A, Sundquist J, Hemminki K. Risks of papillary and follicular thyroid cancer among immigrants to Sweden. Int J Cancer 2011;129:2248-55. 15. Kent WD, Hall SF, Isotalo PA, Houlden RL, George RL, Groome PA. Increased incidence of differentiated thyroid carcinoma and detection of subclinical disease. CMAJ 2007;177:1357-61. 16. Moradi T, Nordqvist T, Allebeck P, Galanti MR. Risk of thyroid cancer among Iranian immigrants in Sweden. Cancer Causes Control 2008;19:221-6. 17. Lee DH, Kim JH, Nam JJ, Kim HR, Shin HR. Epidemiological findings of hepatitis B infection based on 1998 National Health and Nutrition Survey in Korea. J Korean Med Sci 2002;17:457-62. 18. Custer B, Sullivan SD, Hazlet TK, Iloeje U, Veenstra DL, Kowdley KV. Global epidemiology of hepatitis B virus. J Clin Gastroenterol 2004; 38:S158-68. www.kjco.org 77