基于CT增强对肠系膜侵袭性纤维瘤病和胃肠道间质瘤的鉴别诊断

目的探讨肠系膜侵袭性纤维瘤病（MAF）与胃肠道间质瘤（GIST）的CT鉴别特征。 方法回顾性分析53例经病理证实的MAF（14例）和GIST（39例）的CT表现。对病灶的位置、形态和边界、强化方式、病灶内坏死、血管和空气、钙化等征象进行分析。测量长径（LD）、短径（SD）、CT值，并计算LD/SD比值、强化程度。采用t检验和受试者操作特征（ROC）曲线确定有意义的CT征象。当使用单一或多个CT特征时，计算敏感度和特异度。 结果MAF多位于胃肠道外（χ²=10.437，P=0.001）、卵圆形或不规则形（χ²=9.192，P=0.004）、强化均匀（χ²=12.458，P=0.000）、病灶内无坏死（χ²=6.632，P=0.014）及强化程度低（静脉期增加CT值约23.9±8.2 HU）。当联合强化均匀和LD/SD比值诊断MAF的敏感度和特异度分别为92.9%和97.4%。 结论胃肠外肠系膜、卵圆形或不规则形、均匀强化、病灶内无坏死、LD/SD≥1.19、动脉期强期增加CT值≤22 HU、静脉期强期增加CT值≤31 HU等7个CT指标有助于鉴别MAF与GIST。

The differential diagnosis of mesenteric invasive fibromatosis and gastrointestinal stromal tumor based on CT enhancement

ObjectiveTo investigate the CT differential features of mesenteric invasive fibromatosis (MAF) and gastrointestinal stromal tumor (GIST). MethodsCT images of 53 pathologically proven cases of MAF (n=14) and GIST (n=39) were retrospectively reviewed. Location, contour, border, enhancement pattern, presence of necrosis, vessels, and air within the lesion were analyzed. Long diameter (LD), short diameter (SD), LD/SD ratio, degree of enhancement were measured and calculated. Significant CT criteria were identified using t-test, and receiver operating characteristic (ROC) curve. Sensitivity and specificity values were calculated when single or multiple CT criteria were used. ResultsMost of the MAF were extra-gastrointestinal location (χ²=10.437, P=0.001), oval or irregular (χ²=9.192, P=0.004), homogeneous enhancement (χ²=12.458, P=0.000), absence of intra-lesional necrosis (χ²=6.632, P=0.014), lower degree of enhancement (the CT value of venous phase was 23.9±8.2 HU). When homogeneous enhancement and LD/SD ratio were combined, the sensitivity and specificity for diagnosing MAF were 92.9% and 97.4%, respectively. ConclusionThe following seven CT features are helpful to distinguish MAF from GIST: extra-gastrointestinal location, oval or irregular shape, homogeneous enhancement, absence of intra-lesional necrosis, LD/SD≥1.19, increased CT value≤22 HU in arterial phase and CT value ≤31 HU in arterial phase.