1189 胃肠道间质瘤（GIST）：计算机断层扫描特征及CT表现与组织学分级的相关性

1189 Gastrointestinal stromal tumor (GIST): computed tomographic features and correlation of CT findings with histologic grade.

作者信息

Pinaikul Siripom, Woodtichartpreecha Piyanoot, Kanngurn Samornmas, Leelakiatpaiboon Sombat

出版信息

J Med Assoc Thai. 2014 Nov;97(11):1189-98.

PMID:25675685

Abstract

OBJECTIVE

To characterize the CT features and to identify predictors of malignancy from CT of GISTs.

MATERIAL AND METHOD

A retrospective review of CT images of 50 patients with pathologically and immunohistochemically proven GISTs was done by two radiologists and final interpretations were reached by consensus. Images were evaluated for site, size, contour boundary, growth pattern, enhancement pattern, degree of enhancement, necrosis, calcification, ulceration, perilesionalfat stranding, evidence ofbowel obstruction, and signs of malignancy. Categorical variables were compared using Fisher's exact test and continuous variables used the t-test. Univariate and multivariate logistic regression models were used to identify significant predictors ofa high mitotic rate.

RESULTS

Of the 50 patients, the most common location of GISTs was stomach (62%) The mean size was 10.2 cm (SD 5.2 cm). The contour was lobulated in 84%. The boundary was smooth in 84%. The growth pattern was exophytic in 68%. Most of tumors had heterogeneous density on post-contrast images (88%). Necrosis (84%), calcification (14%), ulceration (40%), perilesionalfat stranding (44%), and bowel obstruction (2%) were present in the tumors. The CT signs of malignancy found were adjacent organ invasion (18%), ascites (18%), lymphadenopathy (6%), liver metastasis (20%), andperitoneal seeding (16%). Necrosis and peritoneal seeding were statistically significant independent predictors for high mitotic GISTs in multivariate logistic regression (p<0.05). The probability of a high mitotic rate was 1 (95% CI, 0.40-1.00) in the presence of both necrosis and peritoneal seeding.

CONCLUSION

The stomach was the most common site of GIST The CT features of GIST were lobulated, smooth tumor margins, exophytic growth pattern, and heterogeneous enhancement on post-contrast CT images. Presence of both necrosis and peritoneal seeding were found to be a significant predictor of high mitotic rate of GISTs. The probability of a high mitotic rate was 1 (95% CI, 0.40-1.00).

摘要

目的

描述胃肠道间质瘤（GIST）的CT特征并确定CT上提示恶性的指标。

材料与方法

两名放射科医生对50例经病理和免疫组化证实的GIST患者的CT图像进行回顾性分析，最终通过达成共识得出解读结果。评估图像的部位、大小、轮廓边界、生长方式、强化方式、强化程度、坏死、钙化、溃疡、病灶周围脂肪条索影、肠梗阻征象及恶性征象。分类变量采用Fisher精确检验进行比较，连续变量采用t检验。单因素和多因素逻辑回归模型用于确定高有丝分裂率的显著预测指标。

结果

50例患者中，GIST最常见的部位是胃（62%）。平均大小为10.2 cm（标准差5.2 cm）。84%的轮廓呈分叶状。84%的边界光滑。68%的生长方式为外生性。大多数肿瘤在增强后图像上密度不均匀（88%）。肿瘤内存在坏死（84%）、钙化（14%）、溃疡（40%）、病灶周围脂肪条索影（44%）和肠梗阻（2%）。发现的恶性CT征象有邻近器官侵犯（18%）、腹水（18%）、淋巴结肿大（6%）、肝转移（20%）和腹膜种植（16%）。在多因素逻辑回归中，坏死和腹膜种植是高有丝分裂GIST的统计学显著独立预测指标（p<0.05）。同时存在坏死和腹膜种植时，高有丝分裂率的概率为1（95%可信区间，0.40 - 1.00）。