胃腸間質瘤(GIST)2009-01-01楊梅胃腸間質瘤(GIST)2009-01-011流行病學特點胃腸道間質瘤（gastrointestinalstromaltumor，GIST）是一種少見的源于胃腸道間質細胞的腫瘤，發病率約2/10萬，主要發病人群在40～70歲，中位年齡58歲，男性稍多于女性。本病臨床表現及影像學所見缺乏特異性，確診需要靠病理組織學及免疫組化檢測。流行病學特點胃腸道間質瘤（gastrointestinal2組織學特點theGISTcellsarecloselyrelatedtotheinterstitialcellsofCajal(ICC)組織學上可表現為梭形細胞型、上皮細胞型，或兩者的混合型。分子學上絕大多數該腫瘤表現為c-kit基因的變異及少部分（約5%）患者PDGFRA基因的變異免疫組化絕大多數可檢測到CD117抗體陽性，表明組織或細胞表達c-kit原癌基因蛋白，即屬賴氨酸激酶家族的c-kit原癌基因發生功能獲得性突變導致。有組織學特點theGISTcellsareclosel350-year-oldwomanwithsmall-bowelgastrointestinalstromaltumor(GIST).PhotomicrographofhistopathologicslideshowstypicalGISTcomposedoffasciclesofnondescriptspindlecells.AppearanceonHandEstainissimilartothatofsmoothmuscletumor.50-year-oldwomanwithsmall-b4免疫組化檢查ThetumourscanbepositiveforKIT(95%),CD34(60–70%),ACAT2(smoothmuscleactin;30–40%),S100(5%),DES(desmin;1–2%),andkeratin(1-2%).KITisthemostspecificandsensitivemarker.。另外，CD34（+），S-100（-），GFAP（-）有助于協助鑒別診斷，S-100（-）可除外神經源性腫瘤，GFAP（-）可除外膠質瘤。免疫組化檢查Thetumourscanbeposit5胃腸間質瘤影像學特點課件6臨床特點最常見的間質性腫瘤，僅占胃腸道腫瘤的1-3%。好發于胃（60-70%）、小腸（1/3）、結腸/直腸（5%）、食管（2%）。還有發生于網膜、腸系膜及后腹膜。大多數間質瘤（約60-70%）為良性，且多發生于胃部。這些病灶多偶然發現，均可以手術切除。14％的在眼底及賁門，75％在胃體，11％的胃竇。目前趨向認為小腸間質瘤有潛在惡性傾向，推測其惡性程度的主要指標是腫瘤的大小及細胞核分裂相數目（每50HPF下的數目）臨床特點最常見的間質性腫瘤，僅占胃腸道腫瘤的1-3%。好發于7Fletcher等［2］認為：腫瘤直徑＜2cm和細胞核分裂相數目＜5/50HPF為極低度惡性；直徑2～5cm和＜5/50HPF為低度惡性；直徑5～10cm和＜5/50HPF或直徑＜5cm和6～10/50HPF為中度惡性；直徑＞5cm和＞5/50HPF或直徑＞10cm和＞10/50HPF為高度惡性，但也有直徑小的腫瘤發生轉移的報道。Fletcher等［2］認為：腫瘤直徑＜2cm和細胞核8。Chiappa等［3］報道胃腸間質瘤術后復發或轉移的時間是4～36個月。個別報道時間長達十幾年。。Chiappa等［3］報道胃腸間質瘤術后復發或轉移的時間9臨床癥狀臨床癥狀主要取決于腫瘤的位置及大小，且無特異性的表現，僅表現為飽脹感、消化不良、腹痛及可觸及包塊等癥狀，偶爾癥狀由腫瘤內出血引起。腫瘤出血是由于潰瘍所致。臨床癥狀臨床癥狀主要取決于腫瘤的位置及大小，且無特異性的表現10腫瘤常表現為起源于粘膜下向腔外生長的特性，很少引起腸梗阻。十二指腸的間質瘤引起梗阻性黃疸時易與胰腺癌相混淆。腫瘤位于Vater壺腹部。腫瘤常表現為起源于粘膜下向腔外生長的特性，很少引起腸梗阻。11鋇餐檢查表現為粘膜下邊緣清晰的充盈缺損。（Forty-two-year-oldfemalewithGISTatthegastroesophagealjunction.）鋇餐檢查表現為粘膜下邊緣清晰的充盈缺損。（Forty-two12CT影像學征象邊界清晰不均質的腫塊邊緣強化明顯，厚度不均，中心密度減低。原因是由于出血、壞死、囊變。CT影像學征象邊界清晰不均質的腫塊13Seventy-year-oldmalewithGISTofthestomachwithlivermetastases.Alargeintraluminalmassisseeninthestomach,withheterogenouslivermetastases.Seventy-year-oldmalewithGIS14很多腫瘤發現時已經體積很大，約5-30cm，增強CT表現為不均質強化、腔外生長的腫塊(Fig.2)。較小的原發于胃的間質瘤表現為明顯的強化(Fig.3)，在小腸的原發間質瘤很少有此征象。小腸的間質瘤發現時已經很大且傾向于惡性，絕大多數病灶發生于十二指腸。有的較大的腫瘤平掃時可發現出血很多腫瘤發現時已經體積很大，約5-30cm，增強CT表現為不15Fig.2.—48-year-oldwomanwithsmall-bowelgastrointestinalstromaltumor.Axialcontrast-enhancedCTscanofpelvisshowsexophyticheterogeneouslyenhancingmass(arrow).Fig.2.—48-year-oldwomanwith16Fig.3.—30-year-oldmanwithgastricgastrointestinalstromaltumor.AxialcontrastenhancedCTscanofupperabdomenshowsintensehomogenousenhancementoftumorarisingfromgastricwall(arrow).Fig.3.—30-year-oldmanwithg17偶爾也會在CT上發現腔內的腫瘤(Fig.4).。口服造影劑時可發現粘膜下潰瘍(Fig.5)。還有部分腔外的間質瘤被誤診為胰腺的腫瘤或假性囊腫(Fig.6)。腫瘤與腸管壁常僅通過一個很薄的蒂相連，要認真辨認腫瘤的起源。如果存在腸系膜轉移，轉移灶為邊界清晰、邊緣光滑，無牽拉改變(Fig.7)。偶爾也會在CT上發現腔內的腫瘤(Fig.4).。18Fig.4.—69-year-oldwomanwithgastricgastrointestinalstromaltumor.Axialcontrast-enhancedCTscanofupperabdomenshowslargeintraluminalcomponentoftumor(arrow).Fig.4.—69-year-oldwomanwith19Fifty-six-year-oldmalewithGISTofgastricfundus.PostcontrastCTshowshomogenousintraluminalGISTalongthelessercurve,extendingintothegastrohepaticligament.Fifty-six-year-oldmalewithG20Fig.5.—Gastricgastrointestinalstromaltumor(GIST).

A,Axialcontrast-enhancedCTscanofupperabdomenof69-year-oldwomanshowslargeintraluminalcomponentoftumorwithpocketofgas(arrow).Fig.5.—Gastricgastrointestin21B,In63-year-oldwomanwithgastricGIST,axialcontrast-enhancedCTscanofupperabdomenshowslargeheterogeneouslyenhancingtumorinstomachandulcerfilledwithoralcontrastagent(arrow).B,In63-year-oldwomanwithg22Fig.6.—30-year-oldmanwithgastricgastrointestinalstromaltumor.Fig.6.—30-year-oldmanwithg23B).Thistumorwasoriginallymistakenforinfectedpancreaticpseudocyst.B).Thistumorwasoriginally24[fig.7]76-year-oldmanwithsmall-bowelgastrointestinalstromaltumor.

Axialcontrast-enhancedCTscanofpelvisshowssmoothmesentericmetastasis(arrowheads)atpresentation.

[fig.7]76-year-oldmanwithsm25和小腸的淋巴結相同，胃腸間質瘤可以是小腸管腔瘤樣擴張。(Fig.8).原因：腫瘤迅速生長。腫瘤破壞肌間神經叢。原發腫瘤沒有鈣化，但是，在特殊化療后的轉移灶內偶爾會出現鈣化。和小腸的淋巴結相同，胃腸間質瘤可以是小腸管腔瘤樣擴張。(Fi26Fig.8.—45-year-oldmanwithsmall-bowelgastrointestinalstromaltumor.

AandB,Axialcontrast-enhancedCTscansofmidabdomenshowlargemass(arrow)arisingfromsmallbowel,causinganeurysmaldilatationofbowel.Proximal(arrowheads)anddistalsegmentsofsmallbowelwereofnormalcaliber.Fig.8.—45-year-oldmanwiths27胃腸間質瘤影像學特點課件28腫瘤如果與管腔交通，使腫瘤空洞化及竇道形成。Seventy-seven-year-oldmalewithGISToftheileum.PostcontrastCTshowsalargeintra-abdominalmasswithcentralcavitation.腫瘤如果與管腔交通，使腫瘤空洞化及竇道形成。Seventy-29腫瘤長大過程中，邊緣光滑，僅推擠并不侵犯周圍組織及血管。這一點可以與類癌及腺癌鑒別Fifty-six-year-oldmalewithGISToftheileum.(a)PostcontrastCTshows12cm,partiallynecroticprimarytumourarisingfromthesmallbowel.腫瘤長大過程中，邊緣光滑，僅推擠并不侵犯周圍組織及血管。這一30直腸結腸的間質瘤表現為邊界清晰的壁結節，向管腔內侵犯。Seventy-seven-year-oldmalewithrectalGIST.PostcontrastCTshowstheheterogeneouslyenhancingmasswithintraluminalextension(arrow).直腸結腸的間質瘤表現為邊界清晰的壁結節，向管腔內侵犯。Sev31胃腸間質瘤的轉移途徑淋巴道轉移：到目前為止還沒有文獻有報道。腺癌和淋巴瘤主要為淋巴道轉移。如果發現有淋巴結轉移就應該考慮其他診斷。胃腸間質瘤的轉移途徑淋巴道轉移：32腸系膜轉移腸系膜轉移通常見于腫瘤的復發，與術后腹膜種植相關。也可與較大的小腸的間質瘤同時發現，胃的間質瘤較少見。絕大多數腸系膜的病灶為中心低密度。因為病灶通常較小且遠離原發病灶而漏診。(Fig.10).較大的病灶圍繞腸系膜血管生長，但不引起遠端機靜脈栓塞。(Fig.11).腸系膜轉移腸系膜轉移通常見于腫瘤的復發，與術后腹膜種植相關。33Fig.10.—76-year-oldmanwithsmall-bowelgastrointestinalstromaltumor.Axialcontrast-enhancedCTscanofmidabdomenshowsroundednodule(arrowhead)inmesenteryinkeepingwithmetastases.Metastasisisfarfromsiteofresectedtumor(arrow).Fig.10.—76-year-oldmanwith34Fifty-six-year-oldmalewithGISToftheileum.(a)PostcontrastCT

shows12cm,partiallynecroticprimarytumourarisingfromthesmallbowel.(b)Threeyearslaterpostresectionoftheprimarytumour,peritonealdepositsarepresentintherightlowerquadrant(arrow).Fifty-six-year-oldmalewithG35Fig.11.—75-year-oldwomanwithsmall-bowelgastrointestinalstromaltumor.Axialcontrast-enhancedCTscanofmidabdomenshowslargemesentericmass(arrow)growingaroundmesentericvessels(arrowheads).Thereisnothrombosisofmesentericvessels.Fig.11.—75-year-oldwomanwit36網膜轉移網膜轉移較腸系膜轉移更少見。病灶通常直徑小于2cm，均勻強化。因為網膜是蠕動的，因此在下一次檢查時可能不在同一個位置。腹水非常少見，多見于分子靶向治療之后，由于藥物納稅潴留副作用造成的。網膜轉移網膜轉移較腸系膜轉移更少見。37Fig.12.—76-year-oldmanwithsmall-bowelgastrointestinalstromaltumor.Axialcontrast-enhancedCTscanFig.12.—76-year-oldmanwith38axialT2-weightedfat-suppressedfastspin-echoMRI(B)ofpelvisshowomentalcaking(arrows).axialT2-weightedfat-suppress39肝轉移較小的肝轉移瘤在治療前表現為富血供。增強CT上于門脈期表現為均勻明顯強化；在肝靜脈期完全排空(Fig.13)。但是，在增強圖像上并不是所有的轉移瘤同等程度強化，有的高密度，有的低密度，因為不是同一代的轉移瘤(Fig.14)。肝轉移較小的肝轉移瘤在治療前表現為富血供。40Fig.13.—78-year-oldwomanwithsmall-bowelgastrointestinalstromaltumor.

A,Axialbreath-hold3Dfat-suppressedgradient-echoMRIofliverwithgadoliniumshowsbrighthomogenousenhancementofmetastasis(arrow)inlatearterialphase.Smallerhypovascularmetastasesarealsoevident(arrowheads).

Fig.13.—78-year-oldwomanwit41B,Invenousphase,MRIoflargemetastasisshowscompletewashoutofcontrastmaterial(arrow).Smallerhypovascularmetastasesarealsoevident(arrowheads).B,Invenousphase,MRIoflar42Fig.14.—50-year-oldwomanwithgastricgastrointestinalstromaltumor.Axialcontrast-enhancedCTscanofliverrevealshypovascular(arrow)andhypervascular

(arrowhead)metastases.Fig.14.—50-year-oldwomanwit43Othermetastases.LungmetastasesareextremelyrareinGIST,eveninthepresenceofextensiveliverandperitonealmetastases.這是與平滑肌肉瘤的一個很重要的鑒別點。也沒有明確的腦轉移和骨轉移的報道。Othermetastases.Lungmetastas44ConclusionsThediagnosisofGISTcanbesuggestedonimagingbythepresenceofawell-definedheterogeneouslyenhancingmasswithnecroticcenterarisingfromthemuscularispropriaofthestomachorsmallbowelassociatedwithaprominentextraluminalcomponent。GISTsarelessfrequentlyseenoriginatingfromtheanorectum,colonoroesophagus.Metastases,ifpresentoccurintheliverorperitoneum.ConclusionsThediagnosisofGI45胃腸間質瘤(GIST)2009-01-01楊梅胃腸間質瘤(GIST)2009-01-0146流行病學特點胃腸道間質瘤（gastrointestinalstromaltumor，GIST）是一種少見的源于胃腸道間質細胞的腫瘤，發病率約2/10萬，主要發病人群在40～70歲，中位年齡58歲，男性稍多于女性。本病臨床表現及影像學所見缺乏特異性，確診需要靠病理組織學及免疫組化檢測。流行病學特點胃腸道間質瘤（gastrointestinal47組織學特點theGISTcellsarecloselyrelatedtotheinterstitialcellsofCajal(ICC)組織學上可表現為梭形細胞型、上皮細胞型，或兩者的混合型。分子學上絕大多數該腫瘤表現為c-kit基因的變異及少部分（約5%）患者PDGFRA基因的變異免疫組化絕大多數可檢測到CD117抗體陽性，表明組織或細胞表達c-kit原癌基因蛋白，即屬賴氨酸激酶家族的c-kit原癌基因發生功能獲得性突變導致。有組織學特點theGISTcellsareclosel4850-year-oldwomanwithsmall-bowelgastrointestinalstromaltumor(GIST).PhotomicrographofhistopathologicslideshowstypicalGISTcomposedoffasciclesofnondescriptspindlecells.AppearanceonHandEstainissimilartothatofsmoothmuscletumor.50-year-oldwomanwithsmall-b49免疫組化檢查ThetumourscanbepositiveforKIT(95%),CD34(60–70%),ACAT2(smoothmuscleactin;30–40%),S100(5%),DES(desmin;1–2%),andkeratin(1-2%).KITisthemostspecificandsensitivemarker.。另外，CD34（+），S-100（-），GFAP（-）有助于協助鑒別診斷，S-100（-）可除外神經源性腫瘤，GFAP（-）可除外膠質瘤。免疫組化檢查Thetumourscanbeposit50胃腸間質瘤影像學特點課件51臨床特點最常見的間質性腫瘤，僅占胃腸道腫瘤的1-3%。好發于胃（60-70%）、小腸（1/3）、結腸/直腸（5%）、食管（2%）。還有發生于網膜、腸系膜及后腹膜。大多數間質瘤（約60-70%）為良性，且多發生于胃部。這些病灶多偶然發現，均可以手術切除。14％的在眼底及賁門，75％在胃體，11％的胃竇。目前趨向認為小腸間質瘤有潛在惡性傾向，推測其惡性程度的主要指標是腫瘤的大小及細胞核分裂相數目（每50HPF下的數目）臨床特點最常見的間質性腫瘤，僅占胃腸道腫瘤的1-3%。好發于52Fletcher等［2］認為：腫瘤直徑＜2cm和細胞核分裂相數目＜5/50HPF為極低度惡性；直徑2～5cm和＜5/50HPF為低度惡性；直徑5～10cm和＜5/50HPF或直徑＜5cm和6～10/50HPF為中度惡性；直徑＞5cm和＞5/50HPF或直徑＞10cm和＞10/50HPF為高度惡性，但也有直徑小的腫瘤發生轉移的報道。Fletcher等［2］認為：腫瘤直徑＜2cm和細胞核53。Chiappa等［3］報道胃腸間質瘤術后復發或轉移的時間是4～36個月。個別報道時間長達十幾年。。Chiappa等［3］報道胃腸間質瘤術后復發或轉移的時間54臨床癥狀臨床癥狀主要取決于腫瘤的位置及大小，且無特異性的表現，僅表現為飽脹感、消化不良、腹痛及可觸及包塊等癥狀，偶爾癥狀由腫瘤內出血引起。腫瘤出血是由于潰瘍所致。臨床癥狀臨床癥狀主要取決于腫瘤的位置及大小，且無特異性的表現55腫瘤常表現為起源于粘膜下向腔外生長的特性，很少引起腸梗阻。十二指腸的間質瘤引起梗阻性黃疸時易與胰腺癌相混淆。腫瘤位于Vater壺腹部。腫瘤常表現為起源于粘膜下向腔外生長的特性，很少引起腸梗阻。56鋇餐檢查表現為粘膜下邊緣清晰的充盈缺損。（Forty-two-year-oldfemalewithGISTatthegastroesophagealjunction.）鋇餐檢查表現為粘膜下邊緣清晰的充盈缺損。（Forty-two57CT影像學征象邊界清晰不均質的腫塊邊緣強化明顯，厚度不均，中心密度減低。原因是由于出血、壞死、囊變。CT影像學征象邊界清晰不均質的腫塊58Seventy-year-oldmalewithGISTofthestomachwithlivermetastases.Alargeintraluminalmassisseeninthestomach,withheterogenouslivermetastases.Seventy-year-oldmalewithGIS59很多腫瘤發現時已經體積很大，約5-30cm，增強CT表現為不均質強化、腔外生長的腫塊(Fig.2)。較小的原發于胃的間質瘤表現為明顯的強化(Fig.3)，在小腸的原發間質瘤很少有此征象。小腸的間質瘤發現時已經很大且傾向于惡性，絕大多數病灶發生于十二指腸。有的較大的腫瘤平掃時可發現出血很多腫瘤發現時已經體積很大，約5-30cm，增強CT表現為不60Fig.2.—48-year-oldwomanwithsmall-bowelgastrointestinalstromaltumor.Axialcontrast-enhancedCTscanofpelvisshowsexophyticheterogeneouslyenhancingmass(arrow).Fig.2.—48-year-oldwomanwith61Fig.3.—30-year-oldmanwithgastricgastrointestinalstromaltumor.AxialcontrastenhancedCTscanofupperabdomenshowsintensehomogenousenhancementoftumorarisingfromgastricwall(arrow).Fig.3.—30-year-oldmanwithg62偶爾也會在CT上發現腔內的腫瘤(Fig.4).。口服造影劑時可發現粘膜下潰瘍(Fig.5)。還有部分腔外的間質瘤被誤診為胰腺的腫瘤或假性囊腫(Fig.6)。腫瘤與腸管壁常僅通過一個很薄的蒂相連，要認真辨認腫瘤的起源。如果存在腸系膜轉移，轉移灶為邊界清晰、邊緣光滑，無牽拉改變(Fig.7)。偶爾也會在CT上發現腔內的腫瘤(Fig.4).。63Fig.4.—69-year-oldwomanwithgastricgastrointestinalstromaltumor.Axialcontrast-enhancedCTscanofupperabdomenshowslargeintraluminalcomponentoftumor(arrow).Fig.4.—69-year-oldwomanwith64Fifty-six-year-oldmalewithGISTofgastricfundus.PostcontrastCTshowshomogenousintraluminalGISTalongthelessercurve,extendingintothegastrohepaticligament.Fifty-six-year-oldmalewithG65Fig.5.—Gastricgastrointestinalstromaltumor(GIST).

A,Axialcontrast-enhancedCTscanofupperabdomenof69-year-oldwomanshowslargeintraluminalcomponentoftumorwithpocketofgas(arrow).Fig.5.—Gastricgastrointestin66B,In63-year-oldwomanwithgastricGIST,axialcontrast-enhancedCTscanofupperabdomenshowslargeheterogeneouslyenhancingtumorinstomachandulcerfilledwithoralcontrastagent(arrow).B,In63-year-oldwomanwithg67Fig.6.—30-year-oldmanwithgastricgastrointestinalstromaltumor.Fig.6.—30-year-oldmanwithg68B).Thistumorwasoriginallymistakenforinfectedpancreaticpseudocyst.B).Thistumorwasoriginally69[fig.7]76-year-oldmanwithsmall-bowelgastrointestinalstromaltumor.

Axialcontrast-enhancedCTscanofpelvisshowssmoothmesentericmetastasis(arrowheads)atpresentation.

[fig.7]76-year-oldmanwithsm70和小腸的淋巴結相同，胃腸間質瘤可以是小腸管腔瘤樣擴張。(Fig.8).原因：腫瘤迅速生長。腫瘤破壞肌間神經叢。原發腫瘤沒有鈣化，但是，在特殊化療后的轉移灶內偶爾會出現鈣化。和小腸的淋巴結相同，胃腸間質瘤可以是小腸管腔瘤樣擴張。(Fi71Fig.8.—45-year-oldmanwithsmall-bowelgastrointestinalstromaltumor.

AandB,Axialcontrast-enhancedCTscansofmidabdomenshowlargemass(arrow)arisingfromsmallbowel,causinganeurysmaldilatationofbowel.Proximal(arrowheads)anddistalsegmentsofsmallbowelwereofnormalcaliber.Fig.8.—45-year-oldmanwiths72胃腸間質瘤影像學特點課件73腫瘤如果與管腔交通，使腫瘤空洞化及竇道形成。Seventy-seven-year-oldmalewithGISToftheileum.PostcontrastCTshowsalargeintra-abdominalmasswithcentralcavitation.腫瘤如果與管腔交通，使腫瘤空洞化及竇道形成。Seventy-74腫瘤長大過程中，邊緣光滑，僅推擠并不侵犯周圍組織及血管。這一點可以與類癌及腺癌鑒別Fifty-six-year-oldmalewithGISToftheileum.(a)PostcontrastCTshows12cm,partiallynecroticprimarytumourarisingfromthesmallbowel.腫瘤長大過程中，邊緣光滑，僅推擠并不侵犯周圍組織及血管。這一75直腸結腸的間質瘤表現為邊界清晰的壁結節，向管腔內侵犯。Seventy-seven-year-oldmalewithrectalGIST.PostcontrastCTshowstheheterogeneouslyenhancingmasswithintraluminalextension(arrow).直腸結腸的間質瘤表現為邊界清晰的壁結節，向管腔內侵犯。Sev76胃腸間質瘤的轉移途徑淋巴道轉移：到目前為止還沒有文獻有報道。腺癌和淋巴瘤主要為淋巴道轉移。如果發現有淋巴結轉移就應該考慮其他診斷。胃腸間質瘤的轉移途徑淋巴道轉移：77腸系膜轉移腸系膜轉移通常見于腫瘤的復發，與術后腹膜種植相關。也可與較大的小腸的間質瘤同時發現，胃的間質瘤較少見。絕大多數腸系膜的病灶為中心低密度。因為病灶通常較小且遠離原發病灶而漏診。(Fig.10).較大的病灶圍繞腸系膜血管生長，但不引起遠端機靜脈栓塞。(Fig.11).腸系膜轉移腸系膜轉移通常見于腫瘤的復發，與術后腹膜種植相關。78Fig.10.—76-year-oldmanwithsmall-bowelgastrointestinalstromaltumor.Axialcontrast-enhancedCTscanofmidabdomenshowsroundednodule(arrowhead)inmesenteryinkeepingwithmetastases.Metastasisisfarfromsiteofresectedtumor(arrow).Fig.10.—76-year-oldmanwith79Fifty-six-year-oldmalewithGISToftheileum.(a)PostcontrastCT

shows12cm,partiallynecroticprimarytumourarisingfromthesmallbowel.(b)Threeyearslaterpostresectionoftheprimarytumour,peritonealdepositsarepresentintherightlowerquadrant(arrow).Fifty-six-year-oldmalewithG80Fig.11.—75-year-oldwomanwithsmall-bowelgastrointestinalstromaltumor.Axialcontrast-enhancedCTscanofmidabdomenshowslargemesentericmass(arrow)growingaroundmesentericvessels(arrowheads).Thereisnothrombosisofmesentericvessels.Fig.11.—75-year-oldwomanwit81網膜轉移網膜轉移較腸系膜轉移更少見。病灶通常直徑小于2cm，均勻強化。因為網膜是蠕動的，因此在下一次檢查時可能不在同一個位置。腹水非常少見，多見于分子靶向治療之后，由于藥物納稅潴留副作用造成的。網膜轉移網膜轉移較腸系膜轉移更少見。82Fig.12.—76-year-oldmanwithsmall-bowelgastrointestinalstromaltumor.Axialcontrast-enhancedCTscan