www.ksmrm.org JKSMRM 17(3) : 232-238, 2013 pissn 1226-9751 / eissn 2288-3800 Original Article 악성흉막중피종의병기판정에서자기공명영상의진단적유용성평가 이은솔 채은진 강선지 염유경 이현주 박종천 신소연 최윤영 최준호 도경현울산대학교의과대학, 서울아산병원영상의학과영상의학연구소 목적 : 악성흉막중피종 ( 이하 MPM) 의임상적병기판정에있어자기공명영상 ( 이하 MR) 의진단적유용성을컴퓨터단층촬영 ( 이하 CT) 과비교하였다. 대상및방법 : 1997년부터 2012년까지 MPM으로확인된환자중진단시 CT와 MR을얻은환자 20명 ( 남 : 여 =14:6; 평균연령 = 53.5세 ) 을대상으로하였다. CT 혹은 MR 단독을이용하여두명의영상의학과의사가의견일치하에병기판정을시행하였다. 수술적병기판정을받은환자의경우이와비교하여 CT 단독및 CT와 MR을함께시행하였을때의진단적정확도를평가하였다. 또 CT 단독과 CT와 MR을함께시행하였을때의임상병기의일치도를비교하였다. 결과 : CT를이용한 T stage의정확도는 23.1% (3/13) 였고 MR과함께시행한경우 38.5% (5/13) 였다. CT 및 MR을함께시행한경우수술후수술적병기에서 5명의환자는상위진단을, 3명의환자는하위진단을보였다. CT 단독및 CT와 MR을함께시행한병기를서로비교하였을때 85.0% (17/20) 의일치도를보였고불일치한예 (3명) 에서는함께시행한경우 CT 단독보다상위진단을하였다. 결론 : MPM의병기판정에있어서 MR을함께시행한경우 CT 단독에비해보다높은정확도의병기판정을제공하여수술대상이되는환자에서수술전검사로서중요한역할을수행할것으로기대된다. 서 론 악성중피종 (malignant mesothelioma) 은흉막 (pleura) 이나복막 (peritoneum) 의중피세포 (mesothelial cell) 에서기원하는악성종양으로미국의경우매년대략 3300 명, 우리나라에서는 2010 년의경우연 96 건으로전체암발생의 0.1% 미만에속하는매우드문종양이다 (1, 2). 대부분은석면에노출된과거력이있는환자에게발생하며이중 80% 이상이악성흉막중피종 (malignant pleural mesothelioma, MPM) 으로알려져있다 (3, 4). 최근에는새로운항암제및표적치료제 (targeted agents) 등의개발, 방사선치료, 수술법및다방법병합치료 (multimodality therapy) 등의발달로이환률및사망률이 Received; August 20, 2013 Revised; September 9, 2013 Accepted; September 17, 2013 Corresponding author : Eun Jin Chae, M.D. Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 138-736, Korea. Tel. 82-2-3010-4355, Fax. 82-2-476-0090 E-mail : ejinchae@gmail.com 감소하고있기는하지만대부분완화치료 (palliative treatment) 에불과하고아직도예후는매우좋지않아중앙생존기간은 4 에서 18 개월정도이다 (5-8). 최근에는완치를위해서완전한수술적절제를포함한다방법병합치료들이제시되고있는데이를위해서는적합한환자의선택이필수이다 (9-11). 이환자선택에있어서가장중요한요소중하나는정확한암병기 (cancer stage) 를아는것이다 (9, 11). 악성흉막중피종의암병기를결정하는데있어서중요한것은흉벽 (chest wall) 이나종격동 (mediastinum) 의침범여부및림프절 (lymph node) 과폐로의전이여부인데컴퓨터단층촬영 (computed tomography, CT) 이현재로는진단및병기, 그리고치료반응을보는데있어서일차적인영상기법으로널리사용되고있다 (6, 12-15). 그러나 CT 는흉벽침범을과소평가하는경향이있고또림프절침범여부를평가하는데에도제한이있다 (14, 16). 자기공명영상 (magnetic resonance imaging, MR) 은연조직에대한대조도가매우높아종양의흉벽이나횡격막침범여부를보다손쉽게볼수있어종양의완전절제가능성을평가하는데유리하다 (14, 15). 또최근에는 T1-weighted image (WI) 를 3-dimensional, gradient recalled echo (3D GRE) sequence 의기법을통해더욱높은해상도의사진을얻는것이가능해지고 respiratory dynamic cine 232 Copyrightc2013 Journal of the Korean Society of Magnetic Resonance in Medicine
악성흉막중피종의병기판정에서자기공명영상의진단적유용성평가 이은솔외 233 MR 기법역시더욱발전하였다 (17-19). 이전연구들에서몇차례악성흉막중피종의병기판정에있어서 CT 와 MR 을비교하긴하였지만과거연구이거나이둘을직접비교한연구는드물다 (13, 14, 20, 21). 이는악성흉막중피종의낮은발생률에기인한것으로판단된다. 최근에는폐암 (lung cancer) 에서도 MR 기법의발전에따라점점더정확한진단이가능하다고밝혀지고있고이역시악성흉막중피종에서마찬가지의적용이가능할것으로사료된다 (18, 19). 이에추가연구가필요할것으로보여본연구에서는악성흉막중피종의병기설정에있어서 MR 의정확도 (accuracy) 를알아보고, CT 를단독으로시행하였을때와의비교를해보고자한다. 대상및방법 환자군 1997 년 1 월부터 2012 년 12 월까지본원에내원하였던환자중수술또는생검을통해병리조직검사결과악성흉막중피종으로확인된환자들을대상으로하였다. 총 71 명의환자가병리조직검사결과악성흉막중피종으로확인되었으며이중처음진단당시 CT 와 MR 중한가지검사라도시행하지않은환자는연구에서제외하여총 20 명 ( 남 : 여 = 14:6) 이포함되었다. 연령분포는 41 세에서 73 세까지였고, 평균연령은 53.5 세였다. 연구에포함된환자중수술로병기가확인된환자는총 13 명 (65.0%) 이며이환자들을대상으로수술적병기와 CT, MR 각각의임상적병기를비교하였다. 또전체환자를대상으로 CT 를단독으로시행하였을때와 CT 와 MR 을함께시행하였을때의임상적병기를서로비교하였다. CT 영상기법본원및여러외부병원에서다양한기종으로시행된 CT 영상이연구에포함되었다. 대부분 16 또는 64 채널 CT (Sensation 16, 64, Definition AS+, FLASH; Siemens Medical Solutions, Forchheim, Germany; Light- Speed16, VCT; General Electric Medical Systems, Milwaukee, WI, USA; Mx8000 IDT 16; Philips Medical Systems, Best, Netherlands) 가사용되었으나한환자에서 4 채널의 CT 도사용되었다 (LightSpeedQx/I; General Electric Medical Systems). 모든환자에서전체 thoracic cage 를포함하여조영증강후 CT 가얻어졌고절편 (slice) 의간격및두께는 3 mm 에서 6 mm 사이로연속으로얻었다. MR 영상기법모든 MR 은 1.5T MR 기종이었으며 Magnetom Avanto scanner (Siemens, n=5), Vision scanner (Siemens, n=4), Integra (Philips, n=10), Achieva scanner (Philips, n=1), Signa scanner (GE, n=1) 등으로검사가시행되었다. 모든환자에서전체 thoracic cage 를포함하여조영증강없이 T1WI, T2WI, 그리고조영증강후 T1WI 를축상면 (axial plane), 시상면 (sagittal plane), 그리고관상면 (coronal plane) 의 3 방향으로사진을얻었다. 절편의간격은 6.6~10 mm, 그리고절편의두께는 6~8 mm 로절편사이에는 1.2~2 mm 의틈 (gap) 을두고사진을얻었다. 또 11 명 (55%) 의환자에서는역동적호흡자기공명영상 (dynamic breathing MR imaging) 을얻기위해 real time true Fast Imaging with Steady-state Precession (FISP) sequence 나 3D GRE sequence 를추가로얻었다. 3 명 (15%) 의환자에서는조영증강후 3D GRE sequence 를추가로얻었다. 3D GRE sequence 의경우전체 volume data 를얻은후 2~4 mm 의절편두께로절편사이의틈없이연속으로사진을재구성 (reconstruction) 하였다. 임상적병기판정 2 명의영상의학과의사 ( 각각 13 년, 4 년의판독경험보유 ) 가수술소견및병리소견을모르는상태로합의를통해 CT 단독, 그리고 MR 단독으로임상병기판정을시행하였다. 임상병기판정은 Petavision (Asan Medical Center, Seoul) 이라는 picture archiving and communicating system (PACS) 소프트웨어를이용하여이루어졌다. 병기판정은 International Mesothelioma Interest Group 이제시한 New International Staging System for MPM 을따랐다 (22). 조직검사및수술조직검사는 CT 및투시유도아래경피적흉부세침검사및흉강경 (thoracoscopy) 을통한폐조직검사를통해이루어졌다. 영상진단을통해수술을할수없는경우라고판단된환자를제외하고는진단적흉강경이나탐색개흉술 (exploratory thoracotomy) 을통해수술적병기설정을하거나흉막외폐절제술 (extrapleural pneumonectomy) 을통해수술적치료가이루어졌으며이를통해수술적병기판정이이루어졌다. 자료및통계분석본연구에서사용된모든통계는 SPSS (version 12.0 for Windows, Chicago, IL, USA) 를이용하여구하였다. 수술을시행한환자에서수술적병기를기준으로 CT 단독및 CT 와 MR 을함께시행하였을때의병기의정확도 (accuracy) 를평가하였다. 또전체환자에서 CT 단독병기
234 JKSMRM 17(3) : 232-238, 2013 와 MR 및 CT 를함께시행하였을때의병기를비교하였다. 결 과 전체환자의임상적특성, 임상병기, 수술병기를표 1 에요약하였다 (Table 1). 악성흉막중피종의조직학적아형중상피성중피종 (epithelial mesothelioma) 이 11 명 (52.0%) 으로가장많았고이상성중피종 (biphasic mesothelioma) 이 3 명 (15.0%) 으로두번째로많았으며섬유조직형성중피종 (desmoplastic mesothelioma) 이 1 명 (5.0%) 로가장적었다. 7 명의환자에서는조직학적아형을병리적으로판단하기어려웠다. 생존기간 (survival time) 은 70 일에서 5568 일까지로중간값 (median) 은 458 일이었다. 7 명 (35.0%) 의환자에서수술적치료가이루어졌고 10 명 (50.0%) 의환자에서항암치료, 그리고 3 명 (15.0%) 의환자에서는완화요법 (palliative therapy) 만이이루어졌다. T staging 에있어서수술병기와비교하였을때 CT 는 (3/13, 23.1%) 의정확도를보였으며 CT 및 MR 을함께시행한경우 (5/13, 38.5%) 의정확도를보였다 (Fig. 1). 수술병기와비교하였을때 MR 은 5 명에서수술병기보다하위진단 (downstaged) 을하였지만 3 명에서는수술병기보다상위진단을하였다 (Fig. 2). 전체환자를대상으로 CT 단독및 CT 와 MR 을함께시행한병기를서로비교하였을때 (Fig. 3), 20 명중 17 명 (85.0%) 이일치하였고불일치한경우 (15.0%, 3/20) MR 및 CT 를함께시행한경우에서 CT 단독보다상위진단을하였다 (Fig. 4). 3D GRE sequence 를이용하여검사한 3 명의환자에서는 CT 와 MR 이동일한 T4 stage 를보였으며이에따라수술적병기설정은이루어지지않았다. N staging 에있어서는수술병기와비교하 Table 1. Clinical Characteristics Including Clinical and Surgical Staging of Subjects Patient Age Sex Histology Survival Procedure Treatment CT MR Surgical CT MR Surgical MR No. day TNM TNM TNM stage stage stage technique 1 49 F U 144 Bx C T4N0M0 T4N0M0 IV IV 3D+DB+B 2 62 M E 659 Bx C T4N0M0 T4N0M0 IV IV 3D+DB+B 3 44 M U 180 ET C T2N0M0 T4N0M0 T4N0M0 II IV IV DB+B 4 60 F U 1511 EPP S T2N0M0 T2N0M0 T3N0M0 II II III DB+B 5 55 M E 248 Bx C T4N0M0 T4N0M0 IV IV DB+B 6 41 M B 128 Bx P T4N0M0 T4N0M0 IV IV Basic 7 60 M E 1085 EPP S T4N0M0 T4N0M0 T3N0M0 IV IV III DB+B 8 38 F B 458 ET C T2N0M0 T3N0M0 T4N0M0 II III IV Basic 9 64 F E 441 Bx C T4N0M0 T4N0M0 IV IV 3D+DB+B 10 62 M D 70 EPP S T2N0M0 T3N0M0 T3N0M0 II III III Basic 11 45 M B 517 VATS C T4N0M0 T4N0M0 T3N0M0 IV IV III Basic 12 42 M E 924 ET C T3N0M0 T3N0M0 T4N0M0 III III IV Basic 13 56 M E 137 EPP S T2N0M0 T2N0M0 T2N1M0 II II III Basic 14 52 M E 248 EPP S T4N0M0 T4N0M0 T2N2M0 IV IV III Basic 15 69 M U 571 Bx C T1N0M0 T1N0M0 I I DB+B 16 60 F E 301 EPP S T2N0M0 T2N0M0 T3N1M0 II II IV DB+B 17 50 M E 651 VATS P T2N0M0 T2N0M0 T4N0M0 II II IV Basic 18 58 M E 1223 EPP S T2N0M0 T2N0M0 T2N0M0 II II II DB+B 19 36 F U 813 Bx C T4N3M0 T4N3M0 IV IV DB+B 20 28 M E 191 ET P T4N0M0 T4N0M0 T4N0M0 IV IV IV Basic Note. E, epithelial; B, biphasic, D, desmoplastic, U, unknown; Bx, image-guided biopsy; ET, exploratory thoracotomy; EPP, extrapleural pneumonectomy; VATS, video-assisted thoracoscopic surgery; C, chemotherapy; S, surgery; P, palliative therapy; 3D, contrast-enhanced, 3-dimensional, gradient recalled echo sequence; DB, dynamic breathing imaging; B, Basic, basic MR sequence (3 direction T1 weighted image, T2 weighted image, contrast-enhanced T1 weighted image)
악성흉막중피종의병기판정에서자기공명영상의진단적유용성평가 이은솔외 235 였을때 CT 는 85.0% 의정확도를보였고 MR 은 80.0% 의정확도를보였다. 역동적호흡자기공명영상은 11 명의환자에서이루어졌는데이에의한추가적병기변화는없었다. 고 찰 악성흉막중피종의치료에있어흉막외폐절제술이나확대흉막절제술 / 피질제거술 (extended pleurectomy/ decortication) 을비롯한근치적수술이생존률향상에도움이되는지는논란이있지만육안적완전절제 (macroscopic complete resection) 가가능하다면수술적절제술 Fig. 1. Differences between clinical T stage and corrected surgical T stage in patients with available surgical stage. 을시행하자는쪽으로의견이모아지고있다 (11, 23). 현재는유일한무작위시험인 MARS (Mesothelioma and Radical Surgery) 에이어 MARS-2 가진행중으로근치적수술의효과에대한결론을내어줄것으로기대되고있다 (24). 이러한근치적수술여부를결정하는데에있어서는나이, 동반질환등의임상상외에도임상적병기판정이매우중요하다 (9). 이러한악성흉막중피종의수술전영상진단방법은 CT, MR, fluorodeoxyglucose positron emission tomography (FDG-PET), positron emission tomography (PET)-CT 등의여러가지영상진단방법이사용되고있다 (6, 21, 25). 그러나이들을이용한진단이나임상병기판정및영상진단방법간의비교연구는매우부족한실정이다 (16, 21, 25). 현재가장널리쓰이고있는 International Mesothelioma Interest Group 이제시한악성흉막중피종의병기분류에서도수술적절제가능성을중요시하여국소적으로진행하였지만절제가능한경우를 T3, 기술적으로절제불가능한경우를 T4 로분류하였다 (22). 그러나아직까지 CT 나 MR 을이용한악성흉막중피종의정확한수술전병기판정은매우어려운것으로알려져있다 (6, 14, 26). 본연구에서도악성흉막중피종의수술전병기판정을수술후와비교하였을때 CT (23.1%), MR (42.9%) 모두에서낮은정확도를보였다. 아직까지병기판정의정확도를비교한연구는없지만병기판정에대해연구한다른논문들에서는다양한정확도를간접적으로시사하는결과를제시하였다. Patz 등 (13) 은악성흉막중피종 a b Fig. 2. A representative case of upstaging by MR compared to surgical stage. a. A CT image shows circumferential pleural thickening involving visceral and parietal pleura. Areas of obliteration of extrapleural fat probably over the expected line of endothoracic fascia suggest chest wall invasion (T4) (arrows). b. Gadolinium-enhanced T1-weighted MR image shows some indentation of chest wall by the pleural mass suggesting chest wall invasion (T4) (arrows). However, patient underwent pleuropneumonectomy and surgical and histologic findings revealed no evidence of chest wall invasion (T2).
236 JKSMRM 17(3) : 232-238, 2013 환자에서 CT 의횡격막및흉벽침범의민감도를각각 94% 와 93% 로보고하였고 MR 의경우횡격막및흉벽침범의민감도를모두 100% 로보고하였다. Heelan 등 (14) 은횡격막침범정확도를 CT 및 MR 각각 52% 와 82%, 그리고흉내근막 (endothoracic fascia) 침범및절제가능한흉벽침범의정확도를 CT 및 MR 각각 46% 와 69% 로보고하였다. 본연구에서 CT 의수술전병기판정의정확도가낮은것은환자군설정에따른문제일가능성이있는데, 초기진단시 CT 를먼저시행한후 CT 에서흉곽및종격동등의침범여부, 즉병기가불확실한경우만 MR 을시행하였고이러한환자들이주로환자군에포함되었기때문으로사료된다. Fig. 3. Differences between clinical stage by CT only and CT and MR. MR 의경우 CT 보다는정확도가높았지만기대만큼정확도가높지는않았다. 하지만비록낮은정확도이긴하지만 CT 에비해상대적으로 MR 에서높은정확도를보인점은 CT 에서병기를판단하기어려운환자군이었다는점에서의미가있다. 또다른이유로는긴환자포함기간에걸쳐여러종류의 MR 기종및프로토콜을이용하여다양한 MR 영상이얻어진것이한요인이될수있겠다. 초기프로토콜에는스핀에코계열의 T1WI, T2WI, 그리고조영증강을한 T1WI 만이포함되었으며절편의두께도두껍고공간해상도도낮았다. 가장최근에시행한프로토콜에는 3D 영상을쉽게얻을수있게되어조영증강후 3D GRE sequence 가포함되었다 (17, 27). 3 명의환자에서이를적용하였으며모두 stage IV 로판정되어수술을하지않았지만흉벽이나횡격막침범에높은민감도및특이도를보일것으로기대된다 (17). 역동적호흡자기공명영상역시본연구에서일부환자에서함께시행을하였으나대부분의종양이넓게퍼져있어흉벽과의유착이심해병기판정에도움이되지않았다. 병기판정에있어서 MR 을시행하는가장큰이유는흉벽, 횡격막, 그리고종격동의침범여부등병변의범위를보기위한것이다 (9). MR 에서흉벽여부침범을판단하는중요한방법중하나는흉막외지방 (extrapleural fat) 층이침범당하지않고존재하는지판단하는것이다 (15). 또연조직 (soft tissue) 대조도가높기때문에 CT 에서연조직음영이근육에있는경우이것이근육자체에의한음영인지 Fig. 4. A representative case of upstaging by MR compared to CT. a. A CT image shows pleural effusion with diffuse pleural thickening. Soft tissue density lesions are suspicious in intercostal spaces in the lower portion of hemithorax, however chest wall invasion is not clear. b. Gadolinium-enhanced, 3-dimensional, gradient recalled echo sequence MR image clearly shows enhancing soft tissue lesions in the intercostal spaces suggesting diffuse chest wall invasion (T4) (arrow). a b
악성흉막중피종의병기판정에서자기공명영상의진단적유용성평가 이은솔외 237 종양의침범에의한것인지알기어렵지만 MR 에서는쉽게구별가능하다 (14, 15). 본연구에서도 MR 을 CT 와함께시행하였을때 CT 단독으로병기설정을한경우보다상위진단을한경우는모두이런연조직대조도의차이에의해보다쉽게종양의침범여부를알수있었기때문이다본연구에포함되어있는일부증례에서는 MR 에서는흉벽이나종격동을침범한것처럼보였지만실제수술및병리소견에서는침범하지않은경우도있었다. 이는주로는부분부피인공물 (partial volume artifact) 에의한것으로여겨지며 3D MR 영상을얻음으로써해결가능하다 (28). MR 에서나타나는 T1WI 에서의조영증강이나 T2WI 에서의고신호는종양의침범뿐만아니라주변조직의염증에의해서도매우민감하게나타난다 (29). 본연구의제한점으로는후향적연구이며매우드문질환이라는점때문에환자군의수가작아통계적분석을할수있는표본수를갖추지못했다는것이다. 또다양한프로토콜로 CT 및 MR 을시행하였다는것역시제한점이되겠으나초기의 MR 프로토콜과후기의 3D GRE sequence 가포함된프로토콜과의비교는앞으로의 MR protocol 에대한제안이될수있을것이다. 결 론 악성흉막종피종의병기판정에있어서 MR 을 CT 와함께시행하였을때 CT 를단독으로시행한경우보다높은정확도의병기판정을제공하여수술대상이되는환자에서수술전검사로서중요한부가적역할을수행할것으로기대된다. 그러나 MR 을함께시행하더라도병기판정의정확도가충분히높지않아 fast imaging 을이용한다양한프로토콜을시도한 MR 영상의병기판정의정확도등에대한추가적인연구가필요할것이다. References 1. Jung KW, Won YJ, Kong HJ, Oh CM, Seo HG, Lee JS. Cancer statistics in Korea: incidence, mortality, survival and prevalence in 2010. Cancer Res Treat 2013;45:1-14 2. Teta MJ, Mink PJ, Lau E, Sceurman BK, Foster ED. US mesothelioma patterns 1973-2002: indicators of change and insights into background rates. Eur J Cancer Prev 2008;17:525-534 3. Price B, Ware A. Mesothelioma trends in the United States: an update based on Surveillance, Epidemiology, and End Results Program data for 1973 through 2003. Am J Epidemiol 2004; 159:107-112 4. Delgermaa V, Takahashi K, Park EK, Le GV, Hara T, Sorahan T. Global mesothelioma deaths reported to the World Health Organization between 1994 and 2008. Bull World Health Organ 2011;89:716-724 5. Cao C, Tian DH, Pataky KA, Yan TD. Systematic review of pleurectomy in the treatment of malignant pleural mesothelioma. Lung Cancer 2013;81:319-327 6. Erasmus JJ, Truong MT, Smythe WR, et al. Integrated computed tomography-positron emission tomography in patients with potentially resectable malignant pleural mesothelioma: Staging implications. J Thorac Cardiovasc Surg 2005; 129:1364-1370 7. Scherpereel A, Astoul P, Baas P, et al. Guidelines of the European Respiratory Society and the European Society of Thoracic Surgeons for the management of malignant pleural mesothelioma. Eur Respir J 2010;35:479-495 8. Martino D, Pass HI. Integration of multimodality approaches in the management of malignant pleural mesothelioma. Clin Lung Cancer 2004;5:290-298 9. Neumann V, Loseke S, Nowak D, Herth FJ, Tannapfel A. Malignant pleural mesothelioma: incidence, etiology, diagnosis, treatment, and occupational health. Dtsch Arztebl Int 2013;110: 319-326 10. Sugarbaker DJ, Flores RM, Jaklitsch MT, et al. Resection margins, extrapleural nodal status, and cell type determine postoperative long-term survival in trimodality therapy of malignant pleural mesothelioma: results in 183 patients. J Thorac Cardiovasc Surg 1999;117:54-63 11. Rusch V, Baldini EH, Bueno R, et al. The role of surgical cytoreduction in the treatment of malignant pleural mesothelioma: meeting summary of the International Mesothelioma Interest Group Congress, September 11-14, 2012, Boston, Mass. J Thorac Cardiovasc Surg 2013;145:909-910 12. Nowak AK. CT, RECIST, and malignant pleural mesothelioma. Lung Cancer 2005;49 Suppl 1:S37-40 13. Patz EF, Jr., Shaffer K, Piwnica-Worms DR, et al. Malignant pleural mesothelioma: value of CT and MR imaging in predicting resectability. AJR Am J Roentgenol 1992;159:961-966 14. Heelan RT, Rusch VW, Begg CB, Panicek DM, Caravelli JF, Eisen C. Staging of malignant pleural mesothelioma: comparison of CT and MR imaging. AJR Am J Roentgenol 1999;172:1039-1047 15. Wang ZJ, Reddy GP, Gotway MB, et al. Malignant pleural mesothelioma: evaluation with CT, MR imaging, and PET. Radiographics 2004;24:105-119 16. Boiselle PM, Patz EF, Jr., Vining DJ, Weissleder R, Shepard JA, McLoud TC. Imaging of mediastinal lymph nodes: CT, MR, and FDG PET. Radiographics 1998;18:1061-1069 17. Karabulut N, Martin DR, Yang M, Tallaksen RJ. MR imaging of the chest using a contrast-enhanced breath-hold modified threedimensional gradient-echo technique: comparison with twodimensional gradient-echo technique and multidetector CT. AJR Am J Roentgenol 2002;179:1225-1233 18. Hintze C, Dinkel J, Biederer J, Heussel CP, Puderbach M. New procedures. Comprehensive staging of lung cancer by MRI. Radiologe 2010;50:699-705 19. Kajiwara N, Akata S, Uchida O, et al. Cine MRI enables better therapeutic planning than CT in cases of possible lung cancer chest wall invasion. Lung Cancer 2010;69:203-208 20. Plathow C, Staab A, Schmaehl A, et al. Computed tomography, positron emission tomography, positron emission tomography/ computed tomography, and magnetic resonance imaging for staging of limited pleural mesothelioma: initial results. Invest Radiol 2008;43:737-744
238 JKSMRM 17(3) : 232-238, 2013 21. Zahid I, Sharif S, Routledge T, Scarci M. What is the best way to diagnose and stage malignant pleural mesothelioma? Interact Cardiovasc Thorac Surg 2011;12:254-259 22. Rusch VW. A proposed new international TNM staging system for malignant pleural mesothelioma. From the International Mesothelioma Interest Group Chest 1995;108:1122-1128 23. Treasure T, Lang-Lazdunski L, Waller D, et al. Extra-pleural pneumonectomy versus no extra-pleural pneumonectomy for patients with malignant pleural mesothelioma: clinical outcomes of the Mesothelioma and Radical Surgery (MARS) randomised feasibility study. Lancet Oncol 2011;12:763-772 24. Datta A, Smith R, Fiorentino F, Treasure T. Surgery in the treatment of malignant pleural mesothelioma: recruitment into trials should be the default position. Thorax. 2013 Epub 25. Gill RR. Imaging of mesothelioma. Recent Results Cancer Res 2011;189:27-43 26. Gill RR, Gerbaudo VH, Jacobson FL, et al. MR imaging of benign and malignant pleural disease. Magn Reson Imaging Clin N Am 2008;16:319-339 27. Donmez FY, Yekeler E, Saeidi V, Tunaci A, Tunaci M, Acunas G. Dynamic contrast enhancement patterns of solitary pulmonary nodules on 3D gradient-recalled echo MRI. AJR Am J Roentgenol 2007;189:1380-1386 28. Lee VS, Lavelle MT, Krinsky GA, Rofsky NM. Volumetric MR imaging of the liver and applications. Magn Reson Imaging Clin N Am 2001;9:697-716 29. Weber U, Lambert RG, Rufibach K, et al. Anterior chest wall inflammation by whole-body magnetic resonance imaging in patients with spondyloarthritis: lack of association between clinical and imaging findings in a cross-sectional study. Arthritis Res Ther 2012;14:R3 JKSMRM 17(3) : 232-238, 2013 Added Value of Magnetic Resonance Imaging in Staging of Malignant Pleural Mesothelioma Eunsol Lee, Eun Jin Chae, Sunji Kang, Yoo Kyeong Yeom, Hyun Joo Lee, Jong Chun Park, So Youn Shin, Yoon Young Choi, Joon Ho Choi, Kyung-Hyun Do Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center Purpose : We investigated the possible added value of magnetic resonance imaging (MR) in staging of malignant pleural mesothelioma (MPM) compared to computed tomography (CT). Materials and Methods: We retrospectively enrolled 20 patients (M;F = 14:6; mean age, 53.5 yrs) who diagnosed as MPM by histology and underwent CT and MR at initial evaluation from Jan 1997 to Dec 2012. Two radiologists performed clinical staging by using CT alone or MR alone in consensus. In patients underwent surgery (n = 13), we evaluated the diagnostic accuracy of CT and MR in terms of staging compared to surgical staging. In all patients, we compared clinical staging of CT only and CT with MR. Results: The diagnostic accuracy for T staging of CT only was 23.1% (3/13) and that of combined CT and MR was 38.5% (5/13), respectively. Among 13 patients underwent surgery, surgical stage was higher than combined CT and MR stage in 5 patients, but lower in 3 patients. CT only and combined CT and MR agreed in 85.0% (17/ 20). In cases of disagree (15.0%, 3/20), combined CT and MR showed higher stage than CT only. Conclusion: Combined CT and MR increases the diagnostic accuracy in staging of MPM compared to CT only and is important in determining the appropriate treatment in patients being considered for surgery. Index words : Malignant pleural mesothelioma Magnetic resonance imaging (MR) TNM staging Address reprint requests to: Eun Jin Chae, M.D., Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 138-736, Korea. Tel. 82-2-3010-4355 Fax. 82-2-476-0090 E-mail: ejinchae@gmail.com