胃肠间质瘤影像学特点课件

胃肠间质瘤(GIST)2009-01-01杨梅胃肠间质瘤(GIST)2009-01-011流行病学特点胃肠道间质瘤（gastrointestinalstromaltumor，GIST）是一种少见的源于胃肠道间质细胞的肿瘤，发病率约2/10万，主要发病人群在40～70岁，中位年龄58岁，男性稍多于女性。本病临床表现及影像学所见缺乏特异性，确诊需要靠病理组织学及免疫组化检测。流行病学特点胃肠道间质瘤（gastrointestinal2组织学特点theGISTcellsarecloselyrelatedtotheinterstitialcellsofCajal(ICC)组织学上可表现为梭形细胞型、上皮细胞型，或两者的混合型。分子学上绝大多数该肿瘤表现为c-kit基因的变异及少部分（约5%）患者PDGFRA基因的变异免疫组化绝大多数可检测到CD117抗体阳性，表明组织或细胞表达c-kit原癌基因蛋白，即属赖氨酸激酶家族的c-kit原癌基因发生功能获得性突变导致。有组织学特点theGISTcellsareclosel350-year-oldwomanwithsmall-bowelgastrointestinalstromaltumor(GIST).PhotomicrographofhistopathologicslideshowstypicalGISTcomposedoffasciclesofnondescriptspindlecells.AppearanceonHandEstainissimilartothatofsmoothmuscletumor.50-year-oldwomanwithsmall-b4免疫组化检查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（-）有助于协助鉴别诊断，S-100（-）可除外神经源性肿瘤，GFAP（-）可除外胶质瘤。免疫组化检查Thetumourscanbeposit5胃肠间质瘤影像学特点课件6临床特点最常见的间质性肿瘤，仅占胃肠道肿瘤的1-3%。好发于胃（60-70%）、小肠（1/3）、结肠/直肠（5%）、食管（2%）。还有发生于网膜、肠系膜及后腹膜。大多数间质瘤（约60-70%）为良性，且多发生于胃部。这些病灶多偶然发现，均可以手术切除。14％的在眼底及贲门，75％在胃体，11％的胃窦。目前趋向认为小肠间质瘤有潜在恶性倾向，推测其恶性程度的主要指标是肿瘤的大小及细胞核分裂相数目（每50HPF下的数目）临床特点最常见的间质性肿瘤，仅占胃肠道肿瘤的1-3%。好发于7Fletcher等［2］认为：肿瘤直径＜2cm和细胞核分裂相数目＜5/50HPF为极低度恶性；直径2～5cm和＜5/50HPF为低度恶性；直径5～10cm和＜5/50HPF或直径＜5cm和6～10/50HPF为中度恶性；直径＞5cm和＞5/50HPF或直径＞10cm和＞10/50HPF为高度恶性，但也有直径小的肿瘤发生转移的报道。Fletcher等［2］认为：肿瘤直径＜2cm和细胞核8。Chiappa等［3］报道胃肠间质瘤术后复发或转移的时间是4～36个月。个别报道时间长达十几年。。Chiappa等［3］报道胃肠间质瘤术后复发或转移的时间9临床症状临床症状主要取决于肿瘤的位置及大小，且无特异性的表现，仅表现为饱胀感、消化不良、腹痛及可触及包块等症状，偶尔症状由肿瘤内出血引起。肿瘤出血是由于溃疡所致。临床症状临床症状主要取决于肿瘤的位置及大小，且无特异性的表现10肿瘤常表现为起源于粘膜下向腔外生长的特性，很少引起肠梗阻。十二指肠的间质瘤引起梗阻性黄疸时易与胰腺癌相混淆。肿瘤位于Vater壶腹部。肿瘤常表现为起源于粘膜下向腔外生长的特性，很少引起肠梗阻。11钡餐检查表现为粘膜下边缘清晰的充盈缺损。（Forty-two-year-oldfemalewithGISTatthegastroesophagealjunction.）钡餐检查表现为粘膜下边缘清晰的充盈缺损。（Forty-two12CT影像学征象边界清晰不均质的肿块边缘强化明显，厚度不均，中心密度减低。原因是由于出血、坏死、囊变。CT影像学征象边界清晰不均质的肿块13Seventy-year-oldmalewithGISTofthestomachwithlivermetastases.Alargeintraluminalmassisseeninthestomach,withheterogenouslivermetastases.Seventy-year-oldmalewithGIS14很多肿瘤发现时已经体积很大，约5-30cm，增强CT表现为不均质强化、腔外生长的肿块(Fig.2)。较小的原发于胃的间质瘤表现为明显的强化(Fig.3)，在小肠的原发间质瘤很少有此征象。小肠的间质瘤发现时已经很大且倾向于恶性，绝大多数病灶发生于十二指肠。有的较大的肿瘤平扫时可发现出血很多肿瘤发现时已经体积很大，约5-30cm，增强CT表现为不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偶尔也会在CT上发现腔内的肿瘤(Fig.4).。口服造影剂时可发现粘膜下溃疡(Fig.5)。还有部分腔外的间质瘤被误诊为胰腺的肿瘤或假性囊肿(Fig.6)。肿瘤与肠管壁常仅通过一个很薄的蒂相连，要认真辨认肿瘤的起源。如果存在肠系膜转移，转移灶为边界清晰、边缘光滑，无牵拉改变(Fig.7)。偶尔也会在CT上发现腔内的肿瘤(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和小肠的淋巴结相同，胃肠间质瘤可以是小肠管腔瘤样扩张。(Fig.8).原因：肿瘤迅速生长。肿瘤破坏肌间神经丛。原发肿瘤没有钙化，但是，在特殊化疗后的转移灶内偶尔会出现钙化。和小肠的淋巴结相同，胃肠间质瘤可以是小肠管腔瘤样扩张。(Fi26Fig.8.—45-year-oldmanwithsmall-bowelgastrointestinalstromaltumor.

AandB,Axialcontrast-enhancedCTscansofmidabdomenshowlargemass(arrow)arisingfromsmallbowel,causinganeurysmaldilatationofbowel.Proximal(arrowheads)anddistalsegmentsofsmallbowelwereofnormalcaliber.Fig.8.—45-year-oldmanwiths27胃肠间质瘤影像学特点课件28肿瘤如果与管腔交通，使肿瘤空洞化及窦道形成。Seventy-seven-year-oldmalewithGISToftheileum.PostcontrastCTshowsalargeintra-abdominalmasswithcentralcavitation.肿瘤如果与管腔交通，使肿瘤空洞化及窦道形成。Seventy-29肿瘤长大过程中，边缘光滑，仅推挤并不侵犯周围组织及血管。这一点可以与类癌及腺癌鉴别Fifty-six-year-oldmalewithGISToftheileum.(a)PostcontrastCTshows12cm,partiallynecroticprimarytumourarisingfromthesmallbowel.肿瘤长大过程中，边缘光滑，仅推挤并不侵犯周围组织及血管。这一30直肠结肠的间质瘤表现为边界清晰的壁结节，向管腔内侵犯。Seventy-seven-year-oldmalewithrectalGIST.PostcontrastCTshowstheheterogeneouslyenhancingmasswithintraluminalextension(arrow).直肠结肠的间质瘤表现为边界清晰的壁结节，向管腔内侵犯。Sev31胃肠间质瘤的转移途径淋巴道转移：到目前为止还没有文献有报道。腺癌和淋巴瘤主要为淋巴道转移。如果发现有淋巴结转移就应该考虑其他诊断。胃肠间质瘤的转移途径淋巴道转移：32肠系膜转移肠系膜转移通常见于肿瘤的复发，与术后腹膜种植相关。也可与较大的小肠的间质瘤同时发现，胃的间质瘤较少见。绝大多数肠系膜的病灶为中心低密度。因为病灶通常较小且远离原发病灶而漏诊。(Fig.10).较大的病灶围绕肠系膜血管生长，但不引起远端机静脉栓塞。(Fig.11).肠系膜转移肠系膜转移通常见于肿瘤的复发，与术后腹膜种植相关。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网膜转移网膜转移较肠系膜转移更少见。病灶通常直径小于2cm，均匀强化。因为网膜是蠕动的，因此在下一次检查时可能不在同一个位置。腹水非常少见，多见于分子靶向治疗之后，由于药物纳税潴留副作用造成的。网膜转移网膜转移较肠系膜转移更少见。37Fig.12.—76-year-oldmanwithsmall-bowelgastrointestinalstromaltumor.Axialcontrast-enhancedCTscanFig.12.—76-year-oldmanwith38axialT2-weightedfat-suppressedfastspin-echoMRI(B)ofpelvisshowomentalcaking(arrows).axialT2-weightedfat-suppress39肝转移较小的肝转移瘤在治疗前表现为富血供。增强CT上于门脉期表现为均匀明显强化；在肝静脉期完全排空(Fig.13)。但是，在增强图像上并不是所有的转移瘤同等程度强化，有的高密度，有的低密度，因为不是同一代的转移瘤(Fig.14)。肝转移较小的肝转移瘤在治疗前表现为富血供。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.这是与平滑肌肉瘤的一个很重要的鉴别点。也没有明确的脑转移和骨转移的报道。Othermetastases.Lungmetastas44ConclusionsThediagnosisofGISTcanbesuggestedonimagingbythepresenceofawell-definedheterogeneouslyenhancingmasswithnecroticcenterarisingfromthemuscularispropriaofthestomachorsmallbowelassociatedwithaprominentextraluminalcomponent。GISTsarelessfrequentlyseenoriginatingfromtheanorectum,colonoroesophagus.Metastases,ifpresentoccurintheliverorperitoneum.ConclusionsThediagnosisofGI45胃肠间质瘤(GIST)2009-01-01杨梅胃肠间质瘤(GIST)2009-01-0146流行病学特点胃肠道间质瘤（gastrointestinalstromaltumor，GIST）是一种少见的源于胃肠道间质细胞的肿瘤，发病率约2/10万，主要发病人群在40～70岁，中位年龄58岁，男性稍多于女性。本病临床表现及影像学所见缺乏特异性，确诊需要靠病理组织学及免疫组化检测。流行病学特点胃肠道间质瘤（gastrointestinal47组织学特点theGISTcellsarecloselyrelatedtotheinterstitialcellsofCajal(ICC)组织学上可表现为梭形细胞型、上皮细胞型，或两者的混合型。分子学上绝大多数该肿瘤表现为c-kit基因的变异及少部分（约5%）患者PDGFRA基因的变异免疫组化绝大多数可检测到CD117抗体阳性，表明组织或细胞表达c-kit原癌基因蛋白，即属赖氨酸激酶家族的c-kit原癌基因发生功能获得性突变导致。有组织学特点theGISTcellsareclosel4850-year-oldwomanwithsmall-bowelgastrointestinalstromaltumor(GIST).PhotomicrographofhistopathologicslideshowstypicalGISTcomposedoffasciclesofnondescriptspindlecells.AppearanceonHandEstainissimilartothatofsmoothmuscletumor.50-year-oldwomanwithsmall-b49免疫组化检查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（-）有助于协助鉴别诊断，S-100（-）可除外神经源性肿瘤，GFAP（-）可除外胶质瘤。免疫组化检查Thetumourscanbeposit50胃肠间质瘤影像学特点课件51临床特点最常见的间质性肿瘤，仅占胃肠道肿瘤的1-3%。好发于胃（60-70%）、小肠（1/3）、结肠/直肠（5%）、食管（2%）。还有发生于网膜、肠系膜及后腹膜。大多数间质瘤（约60-70%）为良性，且多发生于胃部。这些病灶多偶然发现，均可以手术切除。14％的在眼底及贲门，75％在胃体，11％的胃窦。目前趋向认为小肠间质瘤有潜在恶性倾向，推测其恶性程度的主要指标是肿瘤的大小及细胞核分裂相数目（每50HPF下的数目）临床特点最常见的间质性肿瘤，仅占胃肠道肿瘤的1-3%。好发于52Fletcher等［2］认为：肿瘤直径＜2cm和细胞核分裂相数目＜5/50HPF为极低度恶性；直径2～5cm和＜5/50HPF为低度恶性；直径5～10cm和＜5/50HPF或直径＜5cm和6～10/50HPF为中度恶性；直径＞5cm和＞5/50HPF或直径＞10cm和＞10/50HPF为高度恶性，但也有直径小的肿瘤发生转移的报道。Fletcher等［2］认为：肿瘤直径＜2cm和细胞核53。Chiappa等［3］报道胃肠间质瘤术后复发或转移的时间是4～36个月。个别报道时间长达十几年。。Chiappa等［3］报道胃肠间质瘤术后复发或转移的时间54临床症状临床症状主要取决于肿瘤的位置及大小，且无特异性的表现，仅表现为饱胀感、消化不良、腹痛及可触及包块等症状，偶尔症状由肿瘤内出血引起。肿瘤出血是由于溃疡所致。临床症状临床症状主要取决于肿瘤的位置及大小，且无特异性的表现55肿瘤常表现为起源于粘膜下向腔外生长的特性，很少引起肠梗阻。十二指肠的间质瘤引起梗阻性黄疸时易与胰腺癌相混淆。肿瘤位于Vater壶腹部。肿瘤常表现为起源于粘膜下向腔外生长的特性，很少引起肠梗阻。56钡餐检查表现为粘膜下边缘清晰的充盈缺损。（Forty-two-year-oldfemalewithGISTatthegastroesophagealjunction.）钡餐检查表现为粘膜下边缘清晰的充盈缺损。（Forty-two57CT影像学征象边界清晰不均质的肿块边缘强化明显，厚度不均，中心密度减低。原因是由于出血、坏死、囊变。CT影像学征象边界清晰不均质的肿块58Seventy-year-oldmalewithGISTofthestomachwithlivermetastases.Alargeintraluminalmassisseeninthestomach,withheterogenouslivermetastases.Seventy-year-oldmalewithGIS59很多肿瘤发现时已经体积很大，约5-30cm，增强CT表现为不均质强化、腔外生长的肿块(Fig.2)。较小的原发于胃的间质瘤表现为明显的强化(Fig.3)，在小肠的原发间质瘤很少有此征象。小肠的间质瘤发现时已经很大且倾向于恶性，绝大多数病灶发生于十二指肠。有的较大的肿瘤平扫时可发现出血很多肿瘤发现时已经体积很大，约5-30cm，增强CT表现为不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偶尔也会在CT上发现腔内的肿瘤(Fig.4).。口服造影剂时可发现粘膜下溃疡(Fig.5)。还有部分腔外的间质瘤被误诊为胰腺的肿瘤或假性囊肿(Fig.6)。肿瘤与肠管壁常仅通过一个很薄的蒂相连，要认真辨认肿瘤的起源。如果存在肠系膜转移，转移灶为边界清晰、边缘光滑，无牵拉改变(Fig.7)。偶尔也会在CT上发现腔内的肿瘤(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和小肠的淋巴结相同，胃肠间质瘤可以是小肠管腔瘤样扩张。(Fig.8).原因：肿瘤迅速生长。肿瘤破坏肌间神经丛。原发肿瘤没有钙化，但是，在特殊化疗后的转移灶内偶尔会出现钙化。和小肠的淋巴结相同，胃肠间质瘤可以是小肠管腔瘤样扩张。(Fi71Fig.8.—45-year-oldmanwithsmall-bowelgastrointestinalstromaltumor.

AandB,Axialcontrast-enhancedCTscansofmidabdomenshowlargemass(arrow)arisingfromsmallbowel,causinganeurysmaldilatationofbowel.Proximal(arrowheads)anddistalsegmentsofsmallbowelwereofnormalcaliber.Fig.8.—45-year-oldmanwiths72胃肠间质瘤影像学特点课件73肿瘤如果与管腔交通，使肿瘤空洞化及窦道形成。Seventy-seven-year-oldmalewithGISToftheileum.PostcontrastCTshowsalargeintra-abdominalmasswithcentralcavitation.肿瘤如果与管腔交通，使肿瘤空洞化及窦道形成。Seventy-74肿瘤长大过程中，边缘光滑，仅推挤并不侵犯周围组织及血管。这一点可以与类癌及腺癌鉴别Fifty-six-year-oldmalewithGISToftheileum.(a)PostcontrastCTshows12cm,partiallynecroticprimarytumourarisingfromthesmallbowel.肿瘤长大过程中，边缘光滑，仅推挤并不侵犯周围组织及血管。这一75直肠结肠的间质瘤表现为边界清晰的壁结节，向管腔内侵犯。Seventy-seven-year-oldmalewithrectalGIST.PostcontrastCTshowstheheterogeneouslyenhancingmasswithintraluminalextension(arrow).直肠结肠的间质瘤表现为边界清晰的壁结节，向管腔内侵犯。Sev76胃肠间质瘤的转移途径淋巴道转移：到目前为止还没有文献有报道。腺癌和淋巴瘤主要为淋巴道转移。如果发现有淋巴结转移就应该考虑其他诊断。胃肠间质瘤的转移途径淋巴道转移：77肠系膜转移肠系膜转移通常见于肿瘤的复发，与术后腹膜种植相关。也可与较大的小肠的间质瘤同时发现，胃的间质瘤较少见。绝大多数肠系膜的病灶为中心低密度。因为病灶通常较小且远离原发病灶而漏诊。(Fig.10).较大的病灶围绕肠系膜血管生长，但不引起远端机静脉栓塞。(Fig.11).肠系膜转移肠系膜转移通常见于肿瘤的复发，与术后腹膜种植相关。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网膜转移网膜转移较肠系膜转移更少见。病灶通常直径小于2cm，均匀强化。因为网膜是蠕动的，因此在下一次检查时可能不在同一个位置。腹水非常少见，多见于分子靶向治疗之后，由于药物纳税潴留副作用造成的。网膜转移网膜转移较肠系膜转移更少见。82Fig.12.—76-year-oldmanwithsmall-bowelgastrointestinalstromaltumor.Axialcontrast-enhancedCTscan