Epithelioid gastrointesinal tumors (GISTs) are less likely to have c-kit gene mutations (and express CD117) than spindle cell GISTs. CD117 negative/c-kit negative GISTs can have platelet-derived growth factor alpha (P...Epithelioid gastrointesinal tumors (GISTs) are less likely to have c-kit gene mutations (and express CD117) than spindle cell GISTs. CD117 negative/c-kit negative GISTs can have platelet-derived growth factor alpha (PDGFRα) gene mutations, overexpress PDGFRα protein and respond to imatinib mesylate. Many cases of CD117-negative/CD117-weakly positive, c-kit mutation negative and PDGFRα mutation positive myxoid epithelioid GISTs and one case of CD117-positive GIST with chondro-myxoid features mimicking chondrosarcoma have been reported. We report a case of myxoid epithelioid GIST with predominance of chondroid and chordoid areas resembling an extraskeletal myxoid chondrosarcoma that was strongly positive for CD117, PDGFRα and DOG1 (Discovered on GIST 1) by immunohistochemistry, but lacked c-kit and PDGFRα gene mutations. It is possible that CD117 is strongly positive if a myxoid epithelioid GIST has chondroid/chordoid appearance, but a larger study is needed to confirm this association. CD117 expression in GISTs is important, because GISTs showing CD117 positivity respond to imatinib. No comment can be made about the prognostic significance of chondroid/chordoid appearance in the GISTs.展开更多
目的探讨胃肠道间质瘤(G I S T)的临床病理、免疫组织化学和基因特征。方法观察3 0例G I S T的病理形态特征、免疫组织化学标记D o g-1、C D 1 1 7、C D 3 4、S M A、S-1 0 0、P G P 9.5、D e s和K i-6 7及K I T和P D G F Rα基因突变...目的探讨胃肠道间质瘤(G I S T)的临床病理、免疫组织化学和基因特征。方法观察3 0例G I S T的病理形态特征、免疫组织化学标记D o g-1、C D 1 1 7、C D 3 4、S M A、S-1 0 0、P G P 9.5、D e s和K i-6 7及K I T和P D G F Rα基因突变情况。结果3 0例G I S T主要是三种病理分型:梭形细胞型2 4例、上皮样细胞型3例和混合细胞型3例。免疫组化D o g-1、C D 1 1 7、C D 3 4阳性,S M A、S-1 0 0、P G P 9.5阴性,且分子检测c-K I T和P D G F Rα基因突变,诊断为G I S T。依据肿瘤的大小,核分裂的多少、K i-6 7指数、肿瘤的原发部位及肿瘤破裂进行危险度分级。结论 G I S T病理形态多变,联合检测D o g-1、C D 1 1 7、C D 3 4、K i-6 7及c-K I T和P D G F Rα基因突变情况对其诊断、鉴别诊断及风险分级、预后、生物靶向治疗提供依据。展开更多
文摘Epithelioid gastrointesinal tumors (GISTs) are less likely to have c-kit gene mutations (and express CD117) than spindle cell GISTs. CD117 negative/c-kit negative GISTs can have platelet-derived growth factor alpha (PDGFRα) gene mutations, overexpress PDGFRα protein and respond to imatinib mesylate. Many cases of CD117-negative/CD117-weakly positive, c-kit mutation negative and PDGFRα mutation positive myxoid epithelioid GISTs and one case of CD117-positive GIST with chondro-myxoid features mimicking chondrosarcoma have been reported. We report a case of myxoid epithelioid GIST with predominance of chondroid and chordoid areas resembling an extraskeletal myxoid chondrosarcoma that was strongly positive for CD117, PDGFRα and DOG1 (Discovered on GIST 1) by immunohistochemistry, but lacked c-kit and PDGFRα gene mutations. It is possible that CD117 is strongly positive if a myxoid epithelioid GIST has chondroid/chordoid appearance, but a larger study is needed to confirm this association. CD117 expression in GISTs is important, because GISTs showing CD117 positivity respond to imatinib. No comment can be made about the prognostic significance of chondroid/chordoid appearance in the GISTs.
文摘目的探讨胃肠道间质瘤(G I S T)的临床病理、免疫组织化学和基因特征。方法观察3 0例G I S T的病理形态特征、免疫组织化学标记D o g-1、C D 1 1 7、C D 3 4、S M A、S-1 0 0、P G P 9.5、D e s和K i-6 7及K I T和P D G F Rα基因突变情况。结果3 0例G I S T主要是三种病理分型:梭形细胞型2 4例、上皮样细胞型3例和混合细胞型3例。免疫组化D o g-1、C D 1 1 7、C D 3 4阳性,S M A、S-1 0 0、P G P 9.5阴性,且分子检测c-K I T和P D G F Rα基因突变,诊断为G I S T。依据肿瘤的大小,核分裂的多少、K i-6 7指数、肿瘤的原发部位及肿瘤破裂进行危险度分级。结论 G I S T病理形态多变,联合检测D o g-1、C D 1 1 7、C D 3 4、K i-6 7及c-K I T和P D G F Rα基因突变情况对其诊断、鉴别诊断及风险分级、预后、生物靶向治疗提供依据。
