Miettinen Markku, Lasota Jerzy, Sobin Leslie H
Department of Soft Tissue Pathology, Armed Forces Institute of Pathology, 6825 16th Street NW, Bldg. 54, Rm. G090, Washington, DC 20306-6000, USA.
Am J Surg Pathol. 2005 Oct;29(10):1373-81. doi: 10.1097/01.pas.0000172190.79552.8b.
Gastrointestinal stromal tumors (GISTs), specific KIT- or PDFGRA-signaling driven mesenchymal tumors, are rare in children and young adults, and their clinicopathologic and molecular genetic profile is incompletely understood. In this study, we analyzed 44 gastric GISTs occurring by the age of 21 years. There were 32 females and 12 males, youngest of whom were a 5-year-old boy and an 8-year-old girl. All but 1 of 25 patients under the age of 16 were girls. The patients most commonly received medical attention because of chronic, insidious gastrointestinal bleeding with anemia, less commonly with acute GI bleeding. Only 1 patient had Carney triad with pulmonary chondroma. None of the patients had family members with GIST. The tumors measured from 1.5 to 24 cm (median, 5.6 cm). A total of 21 tumors with specified location were in the antrum and 8 were in the gastric body. Histologically, 26 tumors were composed of epithelioid cells, 12 of spindle cells, and 6 of combination thereof. Mitotic activity varied form 0 to 65/50 HPF (median, 5/50). All but one of the 24 tumors tested were KIT-positive, and 20 were CD34-positive. Eleven patients developed liver or abdominal metastases, and 6 of them died of tumor surviving 5.5 to 35.5 years (median, 16 years) after the first surgery; three of these tumors had a low mitotic activity and size <10 cm. Twenty-one patients were alive with no evidence for disease 7 to 41 years (median, 17 years) after the first surgery. None of the 13 tumors examined (7 of them 8- to 16-year-old females) had KIT exon 9, 11, 13, or 17 or PDGFRA exon 12 or 18 mutation as typically seen in adult GISTs. Gastric GISTs in children have mainly epithelioid morphology, often occur in antrum, and have a somewhat unpredictable but slow course of disease. Their pathogenesis may differ from that of adult GISTs because no KIT or PDGFRA mutations were found; connection with Carney triad seems infrequent despite demographic and histologic similarities.
胃肠道间质瘤（GISTs）是由特定的KIT或PDFGRA信号驱动的间质性肿瘤，在儿童和年轻人中较为罕见，其临床病理和分子遗传学特征尚未完全明确。在本研究中，我们分析了44例21岁前发生的胃GISTs。其中女性32例，男性12例，最年轻的是一名5岁男孩和一名8岁女孩。16岁以下的25例患者中，除1例之外其余均为女孩。患者最常见的就医原因是慢性、隐匿性胃肠道出血伴贫血，较少见急性胃肠道出血。只有1例患者患有卡尼三联征伴肺软骨瘤。所有患者均无GIST家族史。肿瘤大小从1.5厘米至24厘米不等（中位数为5.6厘米）。共有21例明确位置的肿瘤位于胃窦部，8例位于胃体部。组织学上，26例肿瘤由上皮样细胞组成，12例由梭形细胞组成，6例由两者混合组成。有丝分裂活性从0至65/50高倍视野不等（中位数为5/50）。24例检测的肿瘤中，除1例之外其余均为KIT阳性，20例为CD34阳性。11例患者发生肝转移或腹部转移，其中6例死于肿瘤，首次手术后存活5.5至35.5年（中位数为16年）；这些肿瘤中有3例有丝分裂活性低且大小<10厘米。21例患者在首次手术后7至41年（中位数为17年）仍存活且无疾病证据。所检查的13例肿瘤（其中7例为8至16岁女性）均无成人GISTs中常见的KIT外显子9、11、13或17或PDGFRA外显子12或18突变。儿童胃GISTs主要具有上皮样形态，常发生于胃窦部，疾病进程有些不可预测但较为缓慢。其发病机制可能与成人GISTs不同，因为未发现KIT或PDGFRA突变；尽管在人口统计学和组织学上有相似之处，但与卡尼三联征的关联似乎并不常见。
