Mushtaq Sajid, Mamoon Nadira, Hassan Usman, Iqbal Muhammad, Khadim Muhammad Tahir, Sarfraz Tariq
Department of Histopathology, Armed Forces Institute of Pathology, Rawalpindi, Pakistan.
J Gastrointest Cancer. 2009;40(3-4):109-14. doi: 10.1007/s12029-009-9108-5. Epub 2009 Nov 20.
The rationale of this study was to assess the morphological and immunohistochemical characteristics of gastrointestinal stromal tumor (GIST) along with their risk stratification.
Record of 36 cases diagnosed as GIST over a period of 2 years (January 2007 to December 2008) was retrieved. Slides were reviewed for histological typing, immunohistochemical staining, and mitotic count. Cases were divided into very low, low, intermediate, and high-risk groups according to the Fletcher method of risk stratification (Table 1; Fletcher et al. (Int J Surg Pathol 10:81-89, 2002)). Mean, median, and mode were calculated for quantitative variables like age, tumor size, and mitotic count by using SPSS version 14. Frequencies and percentages were also calculated for qualitative variables like results of immunohistochemistry, tumor site, and histological subtypes.
Out of 36 patients, 14 patients were male, and 22 were female. A total of 14 (39%) patients had tumor size between 2 and 5 cm, 13 (36%) patients had size between 5 and 10 cm, and 9 (25%) patients had size >10 cm. There was no tumor less than 2 cm in size. Twenty-one patients (58%) had mitoses <5/50 high power fields (HPF) while seven (20%) had mitoses between 5 and 10/50 HPF and eight (22%) >10/50 HPF. Thirty-one (86%) of cases were strongly positive for CD117 while CD34 was positive in 81% of the cases. Most frequent histological type was hypercellular spindle cell type, and most frequent site of presentation was stomach. Seven patients fell into low risk, ten patients intermediate risk, and 19 patients in high risk groups. There were no patients in very low risk group.
By using microscopy and immunohistochemical techniques, GISTs can be diagnosed accurately and treated efficiently. Risk stratification and histological subtyping have emerged as efficient tools to predict malignant behavior.
本研究的目的是评估胃肠道间质瘤（GIST）的形态学和免疫组化特征及其风险分层。
检索了2年（2007年1月至2008年12月）期间诊断为GIST的36例病例记录。对切片进行组织学类型、免疫组化染色和有丝分裂计数检查。根据Fletcher风险分层方法（表1；Fletcher等人，《国际外科病理学杂志》10:81 - 89，2002年）将病例分为极低、低、中、高风险组。使用SPSS 14版计算年龄、肿瘤大小和有丝分裂计数等定量变量的均值、中位数和众数。还计算免疫组化结果、肿瘤部位和组织学亚型等定性变量的频率和百分比。
36例患者中，14例为男性，22例为女性。共有14例（39%）患者的肿瘤大小在2至5厘米之间，13例（36%）患者的肿瘤大小在5至10厘米之间，9例（25%）患者的肿瘤大小>10厘米。没有大小小于2厘米的肿瘤。21例患者（58%）的有丝分裂数<5/50高倍视野（HPF），7例（20%）患者的有丝分裂数在5至10/50 HPF之间，8例（22%）患者的有丝分裂数>10/50 HPF。31例（86%）病例的CD117呈强阳性，而81%的病例CD34呈阳性。最常见的组织学类型是高细胞梭形细胞型，最常见的发病部位是胃。7例患者属于低风险组，10例患者属于中风险组，19例患者属于高风险组。没有患者属于极低风险组。
通过显微镜检查和免疫组化技术，可以准确诊断GIST并进行有效治疗。风险分层和组织学亚型分类已成为预测恶性行为的有效工具。
