대한내시경복강경외과학회지 Vol. 10. No. 1, 2007 직장암환자에서수술전신보강방사선화학요법후복강경수술과개복수술의비교 원저 가천의과학대학교길병원외과학교실 박세훈ㆍ오재환ㆍ백정흠 Laparoscopic versus Open Rectal Surgery after Neoadjuvant Chemoradiation for Rectal Cancer Se-Hun Park, M.D., Jae Hwan Oh, M.D., Jeong-Heum Baek, M.D. Department of Surgery, Gil Medical Center, Gachon University of Medicine and Science, Incheon, Korea Purpose: This study aimed to compare the efficacy and safety of laparoscopic surgery and open surgery as treatment for rectal cancer after neoadjuvant chemoradiation. Methods: Patients with mid- to lower rectal cancer underwent either laparoscopic surgery (22 pts) or open surgery (37 pts) after neoadjuvant chemoradiation. Results: The mean age of patients was 58.3 in the laparoscopic surgery group (LG) and 57.1 in the open surgery group (OG). There was no significant difference (p<0.05) between the two groups regarding gender age, the body mass index, the ASA score, associated disease and the need for transfusion. The overall conversion rate was 9% (n=2) in the LG. The mean operation time was 287 minutes and this was 208 minutes in the LG and the OG, respectively (p=0.004). The time to passing gas after surgery was 1.5 days and 2.2 days in the LG and the OG, respectively (p=0.004). There was no significant difference between the two groups regarding the distal margin of the resected specimen, the number of dissected lymph node, morbidity, time to the first meal after surgery and the mean hospital stay. No serious complication or death was reported for the two groups. Conclusion: There is no evidence that laparoscopic rectal surgery after neoadjuvant therapy is inadequate, according to our results and with following the principles of cancer surgery. Sufficient lymph node dissection and a tumor free distal margin of resected bowel were accomplished with laparoscopic surgery. Laparoscopic surgery is safe and feasible, and it is similar to the conventional approach concerning to the morbidity. A future study with a larger number of cases and long-term follow up will be necessary to confirm the value of laparoscopic surgery after neoadjuvant chemoradiation. Key words: Rectal cancer, Neoadjuvant therapy, Chemoradio therapy, Laparoscopic surgery 중심단어 : 직장암, 신보강요법, 방사선화학요법, 복강경수술 서론복강경대장수술은 Jacob 등 1 에의해 1991년처음시행된이래, 낮은유병률과통증, 빠른장운동회복, 빠른식사시작, 재원일수감소와이에따른일상생활로의조기복귀, 낮은장유착등여러장점이보고되고있다. 직장암환자에게수술전신보강방사선화학요법을시행하면암종의크기및병기감소뿐만아니라경우에따라완전관해를보이며, 병기감소를통해근치적절제가능성을높여주고, 2,3 항문보존을도모하며, 4,5 국소재발을줄여 환자의생존율을높일수있는 6,7 장점이부각되고있다. 신보강방사선화학요법후복강경수술은 2003년 Araujo 등 8 에의해수술시간, 수혈요구량, 술중, 술후사망률면에서기존방법과유사하다고발표되었으나이러한연구가부족한실정이다. 이에저자들은이연구를통해수술전신보강방사선화학요법을받은직장암환자를대상으로복강경수술과개복수술의효과와안전성을비교하고자하였다. 대상및방법 1) 대상및조사항목 통신저자 : 백정흠, 인천광역시남동구구월동 1198 우편번호 : 405-760, 가천의과학대학교길병원외과학교실 Tel : 032-460-3241, Fax : 032-460-3247 E-mail : gsbaek@gilhospital.com 본논문의요지는 2006 년대한대장항문학회추계학술대회에서구연되었음. 28 2001년 1월부터 2006년 4월까지수술전신보강방사선화학요법후 2명의수술자에의해복강경수술 (22명) 과개복수술 (37명) 을시행받은직장암환자를대상으로후향적연구를하였다. 수술방법은주로환자의선택에따라결정되었다. 양군의평균추적기간은복강경군 20.4±14개월, 개복군 26.2±16개월 (p=0.174) 로유의한차이는없었다.
박세훈외 2 인 : 직장암환자에서수술전신보강방사선화학요법후복강경수술과개복수술의비교 29 대상환자의기준은나이 18 75세, Karnofsky performance status가 70 이상으로, 원격전이가없으며, 직장수지검사및대장내시경검사상종양이중위부 ( 항문연에서 8 12 cm) 및원위부 ( 항문연에서 4 8 cm) 에위치하고, 복부전산화단층촬영, 골반자기공명영상, 경직장초음파상종양의침습도가 T3 혹은직장주위림프절전이가의심된경우로하였다. 복부팽만을동반한장폐쇄, 재발성종양, 다중복부수술의기왕력, 범발성복막염, 주변장기의침윤, 광범위한장누공, 심한심혈관질환및폐질환, 출혈소인이있는경우는제외하였다. 개복수술에대하여복강경수술의유용성을평가하기위해환자의성별, 나이, 체질량지수, 수술기왕력, 수술시간, 장운동회복기간, 재원기간, 원위부절제연까지의길이, 절제된림프절수, 수술후한달이내사망률에대해 SPSS for windows (v.13.0) 를이용하여 independent T test, Chi-square test로유의성을검정하였고, p value가 0.05 미만일때를통계학적으로유의한것으로판정하였다. 2) 신보강방사선화학요법및수술방법골반부에는평균 5,400 cgy의방사선이조사되었으며, 동기간화학요법은방사선치료첫째주와다섯째주에체면적당 5-FU 400 mg과 leucovorin 20 mg을 5일간정주하였다. 수술은수술전신보강방사선화학요법이끝난지 6 8주후시행하였으며술후 4차례보조항암치료를시행하였다. 저자들이시행한복강경술기를기술하면전신마취하에서환자의자세는변형된쇄석위와 Trendelenburg 자세를취하게하고기복을형성한후투관침은제대부및좌우상하복부에 1개씩 5개 (12 mm, 10 mm 혹은 5 mm) 를설치한다. 수술자는환자의우측에위치하고장간막을내측에서외측방향으로후복막으로부터박리하고, 좌측요관및성선혈관들을확인하여손상이없도록한다. 하장간막동맥의기시부및그위치의하장간막정맥을박리하고클립을이용하여결찰하고절단한다. 에스결장및하행결장을측복벽으로부터박리하고, 저위전방절제술의경우에는하복신경의손상에주의하면서장측골반근막과벽측골반근막사이를박리하여전직장간막절제술을시행하게된다. 골반거근까지박리한후하부직장암의말단부의거리를 2 cm 이상유지하고골반거근상부에서복강경용스테플러를이용하여절단한다. 절단된대장을꺼내기위해좌하복부투관침을 3 5 cm 연장절개하고복벽에비투과성방어막을설치하여종양으로부터절개창이오염되는것을방지한다. 병변을꺼내어하행결장을체외절단한후단단문합기를사용하여경항문문합한다. 복회음절제술의경우고식적방법과같이회음부에서직장하부및항문주위를절제하여직장및하부에스결장을제거하고대장루를조성한다. 투관침을제거할때투관창의출혈여부를확인하고 10 mm 이상되는투관창은근막을봉합하고수술을마친다. 1) 환자의특성 결 환자의남녀비는복강경군에서각각 17 명, 5 명으로 3.4: 1, 개복군에서각각 30명, 7명으로 4.3:1였고, 평균나이는복강경군에서는 58.4세, 개복군에서는 57.1세였다. 환자의비만정도를체질량지수로나타내면복강경군과개복군에서각각 22.8, 22.4로서로유의한차이가없었다 (p=0.679). ASA 및동반된질환 ( 고혈압, 당뇨, 결핵 ) 여부를통해알아본환자의전신상태또한두군간에통계적차이를보이지않았으며 (ASA; p=0.946, 동반질환 ; p=0.889), 종양의위치는복강경군에서중위부직장암 5명, 원위부직장암 17명, 개복군에서중위부직장암 4명, 원위부직장암 33명으로서로유의한차이를보이지않았다 (p=0.272). 복부수술기왕력이있는자는복강경군 7명, 개복군에서 3명이었다 (Table 1). 2) 수술방법및시간 복강경군중중위부직장암환자 5명중 3명이저위전방절제술을시행받았으며, 초저위전방절제술 ( 저위전방절제술에서문합이결장과항문에서이루어진수술 ), 복회음절제술을각각 1명이시행받았고, 원위부직장암환자 17명중 6명이저위전방절제술, 3명이초저위전방절제술, 8명이복회음절제술을시행받았다. 개복군중중위부직장암환자 4명중 2명이저위전방절제술, 각각 1명이초저위전방절제술과복회음절제술을시행받았고, 원위부직장암환자 33 명중 13명이저위전방절제술, 14명이초저위전방절제술, 각각 3명이복회음절제술과 Hartmann씨수술을시행받았으 Table 1. Clinical characteristics of the laparoscopic and open surgery group LG (n=22) OG (n=37) p value Sex Male 17 30 0.725 Female 5 7 Mean age (yr±sd) 58.4 (±7.4) 57.1 (±9.7) 0.577 BMI 22.8 (±2.5) 22.4 (±3.0) 0.679 ASA I 2 3 0.946 II 17 29 III 3 5 Associated disease 5 9 0.889 (HTN, DM, tuberculosis) Tumor location 0.272 Mid rectum 5 4 Lower rectum 17 33 Abdominal operation history 7 3 0.03 LG = laparoscopic surgery group; OG = open surgery group; BMI = body mass index; HTN = hypertension; DM = diabetes mellitus. 과
30 대한내시경복강경외과학회지제 10 권제 1 호 2007 며, 수술방법에따른통계학적차이는보이지않았다 (p= 0.457). 저위전방절제술과초저위전방절제술을시행받은환자중예방적장루술은복강경군, 개복군에서각각 8명 (61.5%), 14명 (46.7%) 로양군간유의한차이는없었다 (p= 0.370)(Table 2). 평균수술시간은복강경군이 287분, 개복군이 208분으로복강경군의시간이길었으나 (p=0.001), 수혈을시행한환자 Table 2. In-hospital progress of the laparoscopic and open surgery group LG (n=22) OG (n=37) p value Type of operation 0.457 LAR 9 15 Ultra LAR 4 15 Miles' operation 9 4 Hartmann's operation 0 3 Conversion 2 (9.1%) Operation time 287 208 0.001 (min, ±SD) (±104.5) (±68.0) Transfusion 11 13 0.261 Time to flatus passage (days) 1.5 2.2 0.001 Time to diet (days) 3.7 4.8 0.379 Hospital stay (days) 18.5 16.2 0.359 Complication Early 3 2 0.351 Bleeding 2 1 Anastomosis leakage 1 0 Ileus 0 1 Late Ileus after discharge 3 1 0.141 Mortality 0 0 LAR = low anterior resection. 수는복강경군이 11명, 개복군이 13명으로차이를보이지않았다 (p=0.261). 3) 항문보존율원위부직장암환자를대상으로항문보존율을알아보면, 복강경군에서 17명중 9명이저위전방절제술또는초저위전방절제술을시행하여 52.9% 의항문보존율을보였고, 개복군에서는 33명중 27명이저위전방절제술또는초저위전방절제술을시행하여 81.8% 의항문보존율을보여, 전체원위부직장암환자로보면 72% 의항문보존율을얻었으며, 개복군이복강경군보다유의하게항문보존율이높았다 (p= 0.031). 4) 개복전환복강경군중개복술로의전환은초기수술군 2명에서이루어졌으며, 모두원위부직장암환자로 1명은 2.5 cm 크기의원위부직장암에대해저위전방절제술중골반강내출혈로개복술로전환을시행하였으며, 다른 1명은수술전신보강방사선화학요법으로완전관해를이룬후복회음절제술중전천골삼출출혈 (presacral blood oozing) 을이유로개복수술로전환하였다. 5) 종양에서원위부절제연까지의길이, 절제된림프절수및종양의병기절제된림프절의수는복강경군이 16.9개, 개복군이 14.5 개로차이를보이지않았으며 (p=0.267), 종양에서원위부절제연까지의길이는복강경군이 3.2 cm, 개복군이 2.7 cm 으로통계학적으로차이를보이지않았다 (p=0.138)(table 3). 환자의병기는수술전 TNM 병기로 2기, 3기가복강경군에서각각 13명, 9명, 개복군에서각각 11명, 26명이었다. 복 Table 3. Pathologic and oncologic result of the laparoscopic and open surgery group LG (n=22) OG (n=37) p value Type of pathology Adenocarcinoma 21 35 Mucinous adenocarcinoma 1 2 Number of harvested lymph node 16.9 (±7.3) 14.5 (±8.3) 0.283 Distal resection margin (cm) 3.2 (±1.7) 2.7 (±2.0) 0.138 Postoperative stage Total Postoperative stage Total CR I II III CR I II III Preoperative stage II 3 3 7 13 1 4 6 11 Preoperative stage III 0 1 4 4 9 0 2 12 12 26 Total 3 4 11 4 22 1 6 18 12 37 Number of down staging after neoadjuvant chemoradiotherapy 11 (50%) 19 (51.4%) 0.92 LG = laparoscopic surgery group; OG = open surgery group; CR = complete response.
박세훈외 2 인 : 직장암환자에서수술전신보강방사선화학요법후복강경수술과개복수술의비교 31 Table 4. Clinicopathologic characteristics of recurrent patients Case 1 Case 2 Case 3 Sex/Age M/46 M/55 M/50 Tumor location Mid rectum Mid rectum Mid rectum Type of operation Ultra LAR LAR LAR TNM stage T3N2M0 T3N1M0 T3N2M0 (LN metastasis (6/20) (1/8) (9/29) /total LN) Neural invasion + Time to recurrence (month) 42 8 3 Metastases Lung Liver Brain LAR = low anterior resection; LN = lymph node. 강경군은 11명 (2기에서 6명, 3기에서 5명 ), 개복군은 19명이 (2기에서 5명, 3기에서 14명 ) 병기감소를보였고양군간유의한차이는없었다 (p=0.92)(table 3). 6) 수술후경과 술후통기시간은복강경군이 1.5일, 개복군이 2.2일로복강경수술군이보다빠른장운동회복을보였고 (p= 0.001), 첫식사까지의기간도복강경군과개복군에서각각 3.7일과 4.8일로복강경군에서보다빠르나유의한차이는아니었다 (p=0.379). 재원기간의경우복강경군이 18.5일, 개복군이 16.2일로차이가없었으며 (p=0.359), 수술후첫번째보조항암요법의여부에따라입원기간의차이를보였다. 7) 유병률및사망률 그외수술후합병증은출혈, 문합부누출, 장폐쇄, 퇴원후장폐쇄가있었으나조기합병증과후기합병증모두복강경군과개복군사이차이는보이지않았다 (p=0.351, p= 0.141). 수술후 1개월이내에합병증으로인한사망자는없었다 (Table 2). 8) 재발 복강경군 20.4±14개월, 개복군 26.2±16개월 (p=0.174) 간의평균추적기간중, 국소재발은없었으며, 원격장기에서의재발이개복수술군총 3예에서보여졌으며, 모두남자, 3기중위부직장암환자로각각폐, 간, 뇌로의전이가확인됐다 (Table 4). 고 복강경수술은개복수술에비해폐합병증의감소, 위장관기능의조기회복, 수술후재원기간의단축, 동통의감소, 찰 미용적효과, 사회로의조기복귀등여러장점이있는것으로알려져왔으며, 앞으로도지속적으로확산되어광범위하게시도되어갈것으로보인다. 그동안대장의악성종양에대해서는근치적수술방법으로서의적합성및투관침암재발에관한의문들이제시되어왔으나, 최근에는결장암의복강경수술에관한다기관, 전향적, 무작위연구가발표되기시작하면서, 개복술에견주어재발률과생존율에차이가없음이밝혀지고, 종양학적안정성이입증되어점차결장암의치료에표준술식으로자리잡아가고있다. 9-11 또한저자들은 2004년발표한복강경대장절제술의조기결과에서도복강경술식이종양학적으로안전함을보고한바있으며, 12 Lacy 등 13 은대장암 I, II기에서는종양의재발률과생존율에차이가없으나, III기환자에서재발및생존율이향상되었다고하여복강경수술의우월성을제시하기도하였다. 직장암에관해서는장기생존율에대한결과들이발표되지는않았지만수술후회복등기존의여러장점과더불어절제된수술조직이종양학적으로안전함을보고하고있다. 10,14 국소진행성직장암에서수술전항암화학요법및방사선병행치료는병기감소, 근치적절제술의증가를도모하고항문괄약근을보존하여환자의삶의질을향상시키고국소재발률을줄인다고한다, 15-17 병기감소는국소재발과생존율을향상시킨다고하며 18 Kim 등 19 은국소적으로진행된직장암에서신보강방사선항암요법후근치적절제술을한경우병리학적으로완전관해된경우에우수한생존율을보이고림프절전이여부및수술방법이생존율에영향을미친다고하였다. 완전관해율은 6 29% 로발표되고있으며, 20,21 원위부직장암에서항문보존율은 59 93% 로보고되고있다. 22-24 본연구에서는완전관해율이복강경수술군에서는 13.6%, 개복수술군에서는 2.7% 를보였고, 원위부직장암에서항문보존율은각각 52.9%, 81.8% 로두군모두 50% 이상의항문보존율을보였으나두군간에통계학적으로차이를보였다. 원위직장암의경우종양학적으로충분한원위부절제연을확보하고, 복강경수술시 double stapling technique으로문합을하는데는여러기술적어려움이있으며, 신보강방사선화학요법후에생길수있는조직의변화로두군으로나누어수술을진행하면, 수술방법에영향을줄수있을것이다. 본연구는두군을비교함에있어초기경험을포함하고있고증례가많지않은한계성을가지고있어향후많은경험의축적이필요하리라생각한다. 수술전항암화학요법및방사선병행치료의단점으로는병기하향으로인하여원래의정확한병기를알기가어렵고, T3 이상의진행된직장암이아닌환자에서방사선항암요법을한경우과잉치료의소지가있다. 직장암에서신보강방사선화학요법후복강경수술과개복수술을비교한연구는드물다. Araujo 등 8 은신보강방사선화학요법후복회음절제술을받은환자 28명 ( 복강경군
32 대한내시경복강경외과학회지제 10 권제 1 호 2007 13명, 개복군 15명 ) 에대한전향적연구를통해안전성과효율성을비교하였는데, 복강경군과개복군의수술시간은각각 228분, 284분으로복강경군에서수술시간이짧았으며평균마취시간도복강경군에서짧았다고하였다. 또한수술중및수술후합병증의빈도는차이가없었고, 13명의복강경군환자에서개복술로전환된경우는없다고하였다. 개복군에비하여복강경군에서절제된평균림프절수가차이가없으며종양학적인면에서차이가없다고알려져있다. 25,26 저자들의경우수술시종양의주동맥기시부부터결찰하고전직장장간막절제를통하여충분한장관의제거및림프절절제를시행하였는데, 개복군과복강경군에서박리된림프절의개수및원위부절제연의길이를비교한결과유의한차이가나타나지않았고, 측방면길이는측정하지않아이에대한비교는분석하지못하였다. 장유착이심하거나예기치않은심한출혈이발생했을때, 복강경술기로해결하기어려운타장기손상이발생한경우는복강경수술의완성을위해무리하게계속하는것은지양해야할것이다. 25 개복전환율은대부분의연구에서 14 33% 사이로 26-29 높게는 41% 에달하는것으로보고되고있다. 본연구에서는개복수술로의전환은총 2명 (9.1%) 이었으며, 각각복회음절제술과저위전방절제술중전천골삼출출혈 (presacral blood oozing) 과골반강내출혈을이유로개복수술로의전환을시행하였다. Araujo 등 8 은신보강방사선화학요법후복회음절제술을시행한복강경군과개복군에서수술중출혈로인한저혈압및요관을포함한장기손상의합병증빈도가각각 15.4%, 26.7% 로발표하였으나저자들의경우는수술중복강경수술군에서 2명에서 (9.1%) 출혈이발생하여전환되었고, 개복군에서는 1명에서 (2.7%) 출혈이발생하였다. 수술시간은복강경군에서 287분, 개복군에서 208분으로복강경군이통계적으로유의하게길었으나 (p=0.001) 경험이축적되면점차단축될수있다고본다. Jang 등 30 은대장절제술의 Learning curve를약 30예로제시하였으며본연구에서는복강경군이총 22예로수술시간이 19예에서부터 (p=0.039) 단축되어 Learning curve를제시할수있었다. 수술후일시적장마비는수술중장이노출되는정도, 수술창의크기, 장에대한물리적자극의정도등에의해발생한다. 수술후첫가스배출까지의시간을보면복강경군에서는 1.5일, 개복군은 2.2일로복강경군에서장운동회복시기가빨랐다. 복강경수술이개복시보다경구섭취가빠르다고보고하고있으나 Binderow 등 31 은복강경군과유의한차이점이없었다고하였고, 경구섭취문제는수술법자체에의한차이가아니라술후치료관습에영향을받는것으로보인다. 한편또하나의회복의지표가될수있는수술후평균재원일은복강경군에서는 18.5일, 개복군은 16.2일로조기경구투여에도불구하고수술후보조항암치 료후퇴원하는환자들로인해수술후평균재원일수는길어졌다. 술후장마비시간의단축으로인해복강경수술군에서는 3.7일만에경구투여가이루어졌으며개복수술군에서는 4.8일만에경구투여가이루어졌으나합병증의여부, 술후재원기간중보조항암화학요법의시행여부, 환자의전신상태및개인사정에변이가심하여입원기간의단축으로연결되지못해수술후평균재원일은통계적으로비교하기가어려웠다. 수술후발생한합병증을비교하면조기에발생한경우는출혈, 문합부누출, 장마비가있었는데두군간에차이를보이지않았고, 퇴원후발생한장마비도차이를보이지않아직장암에서신보강방사선화학요법후복강경수술이개복수술과견주어합병증의빈도에차이가없음을알수가있었다. 결 수술전신보강방사선화학치료후시행한복강경직장절제술은종양학적인면에서충분한림프절절제와절제된장의안전한원위부길이를확보할수있고합병증의차이를보이지않아, 중위부및원위부직장암의수술적치료에있어서안전하고, 적절하며, 유병률면에서개복수술과통계학적차이가없었다. 향후수술전신보강방사선항암치료후복강경수술의가치판단을위해보다많은증례의축적과장기적인조사가필요할것으로생각된다. 론 참고문헌 1) Jacob M, Verdeja J, Goldstein H. Minimally invasive colon resection. Surg Laparosc Endosc 1991;1:144-155. 2) Chen ET, Mohiuddin M, Brodovsky H, Fishbein G, Marks G. Downstaging of advanced rectal cancer following combined preoperative chemotherapy and high dose radiation. Int J Radiat Oncol Biol Phys 1994;30:169-175. 3) Minsky BD, Cohen AM, Kemeny N, et al. Enhancement of radiation-induced downstaging of rectal cancer by fluorouracil and high-dose leucovorin chemotherapy. J Clin Oncol 1992; 10:79-84. 4) Rouanet P, Fabre JM, Dubois JB, et al. Conservative surgery for low rectal carcinoma after high-dose radiation. Functional and oncologic results. Ann Surg 1995;221:67-73. 5) Janjan NA, Khoo VS, Abbruzzese J, et al. Tumor downstaging and sphincter preservation with preoperative chemoradiation in locally advanced rectal cancer: the M. D. Anderson Cancer Center experience. Int J Radiat Oncol Biol Phys 1999;44:1027-1038. 6) Minsky BD, Cohen AM, Enker WE, et al. Preoperative 5-FU, low-dose leucovorin, and radiation therapy for locally advanced and unresectable rectal cancer. Int J Radiat Oncol Biol Phys 1997;37:289-295.
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