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1 Vol 39:(4):2005 원발성과호산구증가증후군환자들중폐침범을보이는환자군의 F18 FDG PET 소견 연세대학교의과대학진단방사선과학교실핵의학과, 연세대학교의과대학호흡기내과학교실 1, 이화여자대학교의과대학진단방사선과학교실 2 이재훈 김태훈 윤미진 허진 김태성 김상진 김형중 1 배문선 2 유영훈 이종두 F18 FDG PET Scan findings in Patients with Pulmonary Involvement in the Hypereosinophilic Syndrome Jae Hoon Lee,.D., Tae Hoon Kim,.D., ijin Yun,.D., Jin Hur,.D., TaeSung Kim,.D., Sang Jin Kim,.D., Hyung Joong Kim,.D. 1, oonsun Pai,.D. 2, Young Hoon Ryu,.D., Jong Doo Lee,.D. Division of Nuclear medicine, Department of Diagnostic Radiology, College of edicine, Yonsei University, Department of Pulmonology, College of edicine, Yonsei University 1, Department of Radiology, College of edicine, Ewha Womans University 2 Purpose: Hypereosinophilic syndrome (HES) is an infiltrative disease of eosinophils affecting multiple organs including the lung. F18 2fluoro2deoxyglucose (F18 FDG) may accumulate at sites of inflammation or infection, making interpretation of whole body PET scan difficult in patients with cancer. This study was to evaluate the PET findings of HES with lung involvement and to find out differential PET features between lung malignancy and HES with lung involvement. aterial and ethods: F18 FDG PET and low dose chest CT scan was performed for screening of lung cancer. Eight patients who showed groundglass attenuation (GGA) and consolidation on chest CT scan with peripheral blood eosinophilia were included in this study. The patients with history of parasite infection, allergy and collagen vascular disease were excluded. CT features and FDG PET findings were meticulously evaluated for the distribution of GGA and consolidation and nodules on CT scan and mean and maximal SUV of abnormalities depicted on F18 FDG PET scan. In eight patients, followup chest CT scan and FDG PET scan were done one or two weeks after initial study. Results: F18 FDG PET scan identified metabolically active lesions in seven out of eight patients. aximal SUV was ranged from 2.8 to 10.6 and mean SUV was ranged from 2.2 to 7.2. Remaining one patient had maximal SUV of 1.3. On followup FDG PET scan taken on from one to four weeks later showed decreased degree of initially noted FDG uptakes or migration of previously noted abnormal FDG uptakes. Conclusions: Lung involvement in the HES might be identified as abnormal uptake foci on FDG PET scan mimicking lung cancer. Followup FDG PET and CT scan for the identification of migration or resolution of abnormalities and decrement of SUV would be of help for the differentiation between lung cancer and HES with lung involvement.(korean J Nucl ed 39(4):239245, 2005) Key Words: F18 FDG PET, False Positive, Hypereosinophilic Syndrome, Lung Cancer, Chest CT 서 F18 2fluoro2deoxyglucose (F18 FDG, 이하 FDG) Received: Accepted: Address for reprints: Young Hoon Ryu,.D., Department of Diagnostic Radiology, Yonsei University College of edicine, Research Institute of Radiological Science, Yonsei University, Yongdong Severance Hospital #14692, Dogokdong, Kangnamgu, Seoul , Korea Tel: , Fax: ryuy@mail.nih.gov 론 양전자방출단층촬영 (PET) 은기존영상검사만으로는정확한진단을내리기어려웠던병변들의특성을평가하고분포를검사하는데자주이용되기시작하여, 현재폐암, 두경부종양, 악성림프종, 그리고, 췌장암을포함한거의신체의모든부분에걸쳐원발성및전이성종양을진단하는데폭넓게사용되고있다. 14) 흉부종양환자의전반적인평가와병기결정에있어서도 FDG PET은예민하고특이적인검사임이잘밝혀져있다. 5,6) 그러나, 염증성혹은감염성질환에서도역시 FDG 축적을보일수있고, 이러한 FDG의비정상적인섭취증가를볼수있는양성질환은 40여가지이상으로 239

2 Jae Hoon Lee, et al. F18 FDG PET Scan findings in Patients with Pulmonary Involvement in the Hypereosinophilic Syndrome 보고되어있다. 5,7) 원발성과호산구증가증후군 (idiopathic hypereosinophilic syndrome) 는백혈구증식성질환혹은그와유사한질환들의집합으로서지속적인호산구의과생산이특징이다. 8) 이증후군은, 원인을설명할수없는과다호산구증가증 (hypereosinophilia) 의지속과신체장기의침범, 이두가지로대변된다. 이증후군의가장심한형태는호산구성백혈병 (eosinophilic leukemia) 의임상양상을보이지만, 원발성과호산구증가증후군을일으키는원인은알수없다. 9) 여러조직과장기가손상을받을수가있고, 가장치명적인경우는심장과중추신경계를침범했을경우이다. 10) 폐침범은원발성과호산구증가증후군환자의약 40% 에서보고되고있고, 자각증상이없거나야간기침, 해소, 천명음, 및호흡곤란의임상증상을보일수있다. 병리학적으로이러한폐병변은미만성의호산구침윤을보인다. 이렇게폐침범을보이는원발성과호산구증가증후군환자에있어서, 흉부방사선소견은비특이적이고일과성간유리음영혹은폐경화를보인다고보고되어있다. 9,11) 전산화단층촬영 (Computed tomography; CT) 에서는간유리음영의 halo를동반하거나동반하지않는작은폐결절들, 혹은주로폐가장자리에서관찰되는간유리음영의국소병변을보일수있다고보고되어있다. 이러한소견들만으로도진단이가능한경우가있으나, 악성폐병변들과유사하게나타나서진단적어려움에빠지게만들기도한다. 본저자들은폐침범을보이는원발성과호산구증가증후군환자군에서, 18 FFDG PET 영상소견을평가하고폐암과의감별진단에도움이될수있는 PET 영상소견을알아보고자하였다. 대상및방법 1. 환자군선정 2003년 8월부터 2004년 11월중순까지폐암검진을목적으로본원에내원하여저선량 CT을시행한환자중, 원인불명의폐병변을보여 FDG PET 촬영을의뢰받은환자군을선별하였다. 이들중, 말초혈액검사상말초과다호산구증가증 (peripheral eosinophilia) 을보인 8명의환자를연구에포함시켰다. 8명의환자들모두이차성말초과다호산구증가증을일으킬수있는원인이되는알러지질환, 기생충감염, 교원성질환, 종양, 혹은투약의과거력이없음을확인하였다. 이들의평균나이는 50세 ( 범위 : 38~65세 ) 였으며, 남성은 5 명, 여성은 3명이었다. 2. 흉부 CT SOATO Sensation 16 (Siemens, Erlagen, Germany) 를사용, 저선량 (120 kvp, 105 ma), 단면두께 5 mm로흉부전산화단층촬영을시행하였다. 3. PET 프로토콜모든환자들은 CT 촬영직후혹은다음날, 전신단층촬영기인 Allegro (Philips, Cleveland, OH, USA) 를사용하여 FDGPET 을시행하였다. 환자들은 FDG 정맥주사전최소 6시간의금식을하였고, 주사직전에측정한혈당치는평균 93 mg/dl ( 범위 : 63~122 mg/dl) 였다. 10 mci (370 mbq) 의 F18 FDG를정맥주사하였고모든환자들은주사후 4 0~60 분이지나전신양전자방출단층촬영을 multiple bed position technique으로촬영하였다. frame 당 1분씩 transmission scan 을얻었고이어서 frame 당 3분씩 emission scan을시행하였다. 모든환자들은앙와위에서양팔을올린채로검사를받았다. PET 영상은 OSE algorithm (4 iteration, 8 subsets) 을이용하여재구성하였다. 4. 혈액검사말초혈액검사는검사전모든환자들에게시행하였고, 말초혈액과다호산구증가증은호산구수치가 /L 이상일때로정의하였다. 혈청검사및의무기록의면밀한조사를통하여이차성과다호산구증가증을일으킬수있는가능한원인을모두배제하였다. 5. 영상판독임상정보와 CT의결과를알지못하는두명의전문의가각각 PET 영상을판독하였다. Transaxial, sagittal, coronal 의세가지단면영상과 projection 영상을동시에보면서분석하였고, CT에서관찰되는간유리음영, 폐경화, 폐결절들의분포와 PET 영상에서보이는병변의 SUV 평균및최대치를연관시켜면밀히판독하였다. F18 FDG 반정량적측정방법을사용시, ROI는횡축단면에서비정상적축적을보이는병소주위로하였으며, SUV 계산시지정된관심영역내의최고치를사용하였으며, 2.5 이상의 peak SUV를비정상으로규정하였다. 결과 1. FDG PET 소견 본연구대상인 8명의환자들에결과를 Table 1에정리하였다. FDG PET 검사상, 8명중 7명에서높은섭취를보였 240

3 이재훈외. 원발성과호산구증가증후군환자들중폐침범을보이는환자군의 F18 FDG PET 소견 Table 1. Demographic Data and Results of Peripheral Blood Eosinophil Counts, FDG PET Scans, Chest Radiographs, and Chest CT Scans Case Age Ses F F F WBC (/ul) 9,000 8,300 6,500 7,300 8,200 8,400 10,200 9,400 Eosinophil (%) GGA: Ground glass attenuation Followup Blood Eosinophil Normalized after 1 week 27.1% after 3 weeks Normalized after 3 weeks 38% after 1 month 10.8% after 2 weeks 21.1% after 1 week 8.1% after 3 weeks Normalized after 1 month SUV Palin Chest XRay Chest CT scan Peak ean Nodule Consolidation Nodule Halo GGA Consolidation Table 2. Summary of Followup FDG PET and Chest CT Scan Findings Case SUV Follow up PET Follow up Chest CT Initial Followup Size Number Location Size Number Location Peak ean Peak ean *I *I igration igration D : Decreased I : Increased : No change : Not Available due to resolution of lesions. * There was a newly developed groundglass attenuation lesion in the followup CT scan, however, its metabolic activity was too low to be identified on followup FDG PET. 다. 이들에있어서 peak SUV는 2.8~10.6 ( 평균 : 6.4±2.6), mean SUV는 2.2~7.2 ( 평균 : 4.1±1.6) 로측정되었다 (Fig. 1A, Fig 2A). 나머지 1명에서 peak SUV는 1.3, 그리고, mean SUV는 0.7로측정되었다. 환자들은평균 15.8일 ( 범위 : 7~30일 ) 후추적검사로 FDG PET, 흉부 CT, 그리고, 혈액검사를시행하였다. 이전검사에서비정상적으로높은섭취를보였던 7명중 6명에서추적검사로시행한 FDG PET 검사상, peak SUV 및 mean SUV의감소를보였다 (Table 2, Fig. 1C, Fig. 2C). 이중 2명에서는 SUV의감소와함께병변부위의이동이관찰되었으며이러한변화소견들은흉부 CT 소견과도일치하였다 (Table 2, Fig. 1C). 7명중나머지 1 명과초기에비교적낮은 SUV를보였던 1명은, 추적검사상 FDG의이상섭취를보이지않았고흉부 CT에서도병변은소실되었다. 2. 흉부 CT 소견흉부단순방사선촬영검사상 5명의환자에서결절성병변, 1명에서기강경화소견을보였으며, 나머지 2명은정상 소견을보였다. 흉부 CT소견은주위에 halo를동반한결절성병변으로보이는경우가제일많았으며 (n=5), 간유리음영 (n=2), 혹은기강경화 (n=1) 소견을보였다 (Fig. 1B, Fig. 2B). 추적검사로시행한흉부 CT상, 6명에서는병변의크기및범위가감소하였으며이중 2명에있어서는병변의이동을보였다 (Fig. 1D, Fig. 2D). 그외간유리음영만을보였던 2 명은추적검사상그병변이소실되었다. 고찰 흉부단순방사선촬영과 CT는폐암이의심되는환자에게서흔히시행되는검사다. 이검사들은해부학적및형태학적정보를제공해주지만, 양성과악성의여부를정확히감별해주지는못한다. 그래서, 진단은객담세포검사나조직검사가필요하게된다. 한보고에서는, 방사선학적으로감별이어려운병변들을흉강경으로절제한결과 50% 이상에서양성으로밝혀졌다고보고하였다. 12) 그런맥락에서, 비침습 241

4 Jae Hoon Lee, et al. F18 FDG PET Scan findings in Patients with Pulmonary Involvement in the Hypereosinophilic Syndrome A B C D Figure 1. Coronally and axially reconstructed PET images (A) revealed focal area of hypermetabolic focus on LUL lateral portion which corresponded to focal consolidation and GGA on initial CT scan (B). 3 weeks followup PET images (C) showed decreased degree of FDG uptakes and migration of GGA and consolidation area to posterior portion of same lobe on CT scan (D). 적으로이러한병변들을평가할수있는정확한검사방법이있다면, 기존의불필요하고고가이면서도진단적이지못한 검사들을피할수있을것이다. 그러나, 비종양성흉부질환에있어서도 18 FFDG 섭취가증가되는사례들이보고되어 242

이재훈외. 원발성과호산구증가증후군환자들중폐침범을보이는환자군의 F18 FDG PET 소견 A B C D

5 이재훈외. 원발성과호산구증가증후군환자들중폐침범을보이는환자군의 F18 FDG PET 소견 A B C D Figure 2. Initial FDG PET images (A) revealed focal area of mild degree of hypermetabolic focus on RUL which was improved on 1 week followup PET study (C). CT scan (B) demonstrated multiple nodules and halos and GGA on corresponding areas which were also improved on followup CT scan (D). 243

6 Jae Hoon Lee, et al. F18 FDG PET Scan findings in Patients with Pulmonary Involvement in the Hypereosinophilic Syndrome 왔다. 5,7,13,14) 이런위양성결과는감염성, 염증성, 교원성, 의인성질환과심지어는정상생리적인경우에서도관찰된다고한다. 원발성과호산구증가증후군은원인을발견할수없는과다호산구증가증의오랜지속및여러신체장기침범을특징으로하는질환군이다. 15,16) 질환자체의희귀성과진단에대한불확실성때문에, 질환분포나환경에의한영향등부차적인정보는알려진바가거의없다. 17) 이질환은주로 20세에서 50세사이의남성들에게서발병하지만, 인종이나문명에따른차이는없다고보고되어있다. 이증후군을조기에진단해야하는이유는치료가즉각적으로시행될경우예후가매우좋아지기때문이다. 17) 원발성과호산구증가증후군환자가폐침범을보이는예에서 FDG 섭취가보고된바는없었다. 본증례들에서는 PET 검사상폐가장자리에비정상적 FDG 섭취를보였으며, 이부위는처음 CT에서관찰된병소와일치하였다. 8명중 7명에서비정상적으로높은 SUV를보였다 ; 최고 SUV 는 2.8~10.6였으며, 평균 SUV는 2.2~7.2으로측정되어악성종양의경우와유사한수치를보이기까지했다. 결과적으로, FDG PET 영상만으로악성과양성을감별하는것은어려운위양성결과를초래하였다. 원발성과호산구증가증후군의발병기전은아직도불분명하지만, 독성양이온성단백질을포함하는호산구성과립이분비되어조직손상을일으킨다고알려져있다. 이러한독성물질에는 major basic protein, eosinophil peroxidase, eosinohpilderived neurotoxin, 그리고, eosinophil cationic protein 등이있다. 호산구는또한특정 cytokine 을분비하는데, 이물질에의해추가적인호산구의동원반응이일어나며조직손상을가속시키고면역체계를변화시킨다. 또한, 침윤된호산구가 respiratory burst pathway 를거쳐생산해내는산화성물질에의해조직손상을악화시킨다고알려져있다. 정확히언제어떻게혈중호산구에서과립을분비하는지는알수없지만이것이원발성과호산구증가증후군과연관된조직손상을설명할수있을것으로생각된다. 19) 병리적으로폐침범부위에는미만성의호산구침윤이관찰되는데, 비정상적인 FDG의섭취는병변부위로활성화된백혈구들이이동해서생긴것으로생각되며, 여러 PET 임상결과에서도염증성및감염성질환에서 FDG의높은섭취를보이는것으로나타났다. 20,21) 이러한결과는, 염증세포들이활성화될때당전달체의발현이증가되고이와더불어 cytokine 및성장인자들이 deoxyglucose 에대한당전달체의친화력을상승시켜결과적으로염증부위에정상조직보다높은 FDG의축적을보이게되는것으로설명할수있다. 22) 흉부전산화단층촬영은원발성과호산구증가증후군의진단에도움을줄수있기도하다. 알려진 CT 소견으로는폐가장자리의간유리음영의 halo를가진결절성병변들, 혹은양측폐야에서관찰되는간유리음영병소들이관찰될수있는것으로보고되고있다. 주로병변은폐가장자리에위치하며어느폐엽에서도보일수있다. 또한질환이진행되거나회복되면서이런병변들이이동하거나일과성으로소실되는소견이자주관찰된다고보고되어있다. 23) 본연구에서도초기에폐가장자리에서관찰되던간유리음영의 halo를가진결절성병변이나폐경화소견들이, 과다호산구증이호전되거나지속되면서이동하거나사라지는소견을보였다. 그러나, 보고된 CT 소견들은비특이적이어서, 감별진단으로감염성질환 ( 진균성질환 ), 종양 ( 폐선암, 세기관지폐포암종, 전이암 ), Wegener 육아종증등을고려할수있고, 더욱이본연구에서처럼악성폐종양과비슷한정도의 FDG 의높은섭취를보이는병변일경우, 정확한진단은더욱어려워질수도있다. 결론적으로, 원발성과호산구증가증후군환자들중폐침범을보이는환자에서 FDG PET는폐암과유사한정도의높은섭취를보이는위양성결과가많았으며, 한번의검사만으로는악성과양성을감별하는것은어려웠다. 이런경우, 혈액검사소견을참조하고, 추적검사로 CT 및 FDG PET검사를시행하여병변의위치이동이나소실여부및 FDG 섭취의감소여부등을확인하여보는것이원발성과호산구증가증후군환자에있어서폐침범의경우와폐암을감별하는데도움을줄수있을것으로생각된다. 요약 목적 : F18 FDG PET 검사는염증성이나감염성병변에도위양성소견을보일수있으며이로인하여악성종양과의감별진단을어렵게만드는경우가있다. 원발성과호산구증가증후군 (Hypereosinophilic syndrome) 은폐를포함한여러장기에호산구의침윤을보이는염증성질환이다. 본연구를통하여이런폐침범을보이는원발성과호산구증가증후군환자에있어서 PET 소견을분석하고비정상적인높은섭취를보이는경우폐암과감별되는소견을알아보고자하였다. 대상및방법 : 폐암검진을목적으로시행한저선량흉부 CT 상결정및간유리음영, 기강경화소견을보인환자들중혈액검사상말초호산구과다증을보인환자들을대상으로 FDG PET 검사를시행하였다. 이들중, 기생충질환등의이차성말초과다호산구증가증의원인을있는경우연구에서제외되었다. 총 8명환자들의흉부 CT는결절, 간유 244

7 이재훈외. 원발성과호산구증가증후군환자들중폐침범을보이는환자군의 F18 FDG PET 소견 리음영, 그리고기강경화등의병변소견등으로구분하였으며그병변위치에상응하는 FDG PET에서보이는병변의 maximal 및 mean SUV에관하여대조분석하였다. 8명모두 14주후추적검사를시행하여혈액검사및 PET 과흉부 CT에서관찰되었던병변의변화소견을살펴보았다. 결과 : 처음시행한 FDG PET 검사상, 8명중 7명에서높은섭취를보였으며 peak SUV는 2.8~10.6 ( 평균 : 6.4±2.6), mean SUV는 2.2~7.2 ( 평균 : 4.1±1.6) 로측정되었다. 나머지 1명에서 peak SUV는 1.3, 그리고, mean SUV는 0.7로측정되었다. 환자들은평균 15.8일 ( 범위 : 7일~30일 ) 후추적검사로 18 FFDG PET, 흉부 CT, 그리고, 혈액검사를시행받았다. PET 추적검사상이전에높은섭취를보였던 7명중 6명에서 peak 및 mean SUV의감소를보였고이전에높은섭취를보인나머지 1명과낮은섭취를보인 1명에서는병변이완전히소실되었다. 이러한변화소견은흉부 CT 추적검사소견과도일치하였다. 결론 : 원발성과호산구증가증후군환자군에서폐침범을보이는경우, 폐병변은 FDG PET 영상에서폐암과유사한정도의높은섭취를보이는위양성결과를나타내어한번의 PET 검사만으로는양성과악성을감별할수없었다. 이러한경우, 추적검사로 CT 및 18 FFDG PET를시행하여병변의위치및범위, SUV의변화소견을같이보는것이원발성과호산구증가증후군환자에있어서보일수있는폐침범소견과악성종양을감별하는데도움을줄수있을것으로생각된다. References 1. Hustinx R, Benard F, Alavi A. Wholebody PET imaging in the management of patients with cancer. Semin Nucl ed 2002;32: Rohren E, Turkington TG, Coleman RE. Clinical application of PET in oncology. Radiology 2004;231: Coleman RE. PET in lung cancer. J Nucl ed 1999;40: Rades D, Kuhnel G, Wildfang A, Borner AR, Chmoll HJ, Knapp W. Localised disease in cancer of nknown primary (CUP): the value of positron emission tomography (PET) for individual therapeutic management. Ann Oncol 2001;12: Yang SN, Liang JA, Lin FJ, Kwan AS, Kao CH, Shen YY. Differentiating benign and malignant pulmonary lesions with FDGPET. Anticancer Res 2001;21: Costa DC, Visvikis D, Crosdale I, et al. Positron emission and computed Xray tomography: a coming together. Nucl ed Commun 2003;24: Bakheet S, Saleem, Powe J, AlAmro A, Larsson SG, ahassin Z. F18 fluorodeoxyglucose chest uptake in lung inflammation and infection. Clin Nucl ed 2000;25: Peter F. Weller, Glenn J. Bubley. The idiopathic hypereosinophilic syndrome. Blood 1994:83; Winn RE, Kollef H, eyer JI. Pulmonary involvement in the hypereosinophilic syndrome. Chest 1994;105: Schooley RT, Flaum A, Gralnick HR, Fauci AS. A clinicopathologic correlation of the idiopathic hypereosinophilic syndrome. II. Clinical manifestations. Blood 1981;58: Epstein D, Taormina V, Gefter WB, et al. The hypereosinophilic syndrome. Radiology 1981;140: ack J, Hazelrigg SR, Landreneau RJ, Acuft TE. Thoracoscopy for the diagnosis of the indeterminate solitary pulmonary nodule. Ann Thorac Surg 1993;56: Kavanagh PV, Stevenson AW, Chen Y, Clark PB. Nonneoplastic diseases in the chest showing increased activity on FDG PET. AJR Am J Roentgenol 2004;183: Asad S, Aquino SL, Piyavisetpat N, Fischman AJ. Falsepositive FDG positron emission tomography uptake in nonmalignant chest abnormalities. AJR Am J Roentgenol 2004 Apr;182: Chusid J, Dale DC, West BC, Wolff S. The hypereosinophilic syndrome: analysis of fourteen cases with review of the literature. edicine 1975;54: Parrillo JE, Fauci AS, Wolff S. Therapy of the hypereosinophilic syndrome. Ann Intern ed 1978;89: BritoBabapulle F. The eosinophilias, including the idiopathic hypereosinophilic syndrome. Br J Haematol 2003;121: Fraser RG, Pare JAP. Diagnosis of disease of the chest. 3 rd ed. Philadelphia: Saunders, 1989; Yamada S, Kubota K, Kubota R, Ido T, Tamahashi N. High accumulation of fluorine18 fluorodeoxyglucose in turpentine induced inflammatory tissue. J Nucl ed 1995;7: Sugawara Y, Gutowski TD, Fisher SJ, Brown RS, Wahl RL. Uptake of positron emission tomography tracers in experimental bacterial infections: a comparative biodistribution study of radiolabeled FDG, thymidine, Lmethionine, 67 Gacitrate, and 125 IHSA. Eur J Nucl ed 1999;26: Brudin LH, Valind SO, Rhodes CG, Pantin CF, Sweatman, Jones T, Hughes J. Fluorine18 deoxyglucose uptake in sarcoidosis measured with positron emission tomography. Eur J Nucl ed 1994;21: Kang EY, Shim JJ, Kim JS, Kim KI. Pulmonary involvement of idiopathic hypereosinophilic syndrome: CT findings in five patients. J Comput Assist Tomogr 1997;21: Kim Y, Lee KS, Choi DC, Primack SL, Im JG. The spectrum of eosinophilic lung disease: radiologic findings. J Comput Assist Tomogr 1997;21:

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ÀÌ»ó¹Î 255 Table 1. Summary of CT Features and FDG-PET Findings of Progressive Massive Fibrosis in 11 Patients with Pneumoconiosis Case No. Patient Data Age (year) Sex CT Findings PET Findings Location Size (cm)