多排螺旋CT在诊断胃癌侵犯胃裸区中的价值

Value of Multi-Detector CT in Diagnosis of Bare Area Involvement in Gastric Carcinoma

目的研究胃癌侵犯胃裸区(gastricbarearea,GBA)的CT表现和解剖基础,探讨多排螺旋CT在诊断中的价值。方法回顾性分析196例连续性胃癌病例的CT资料,其中GBA受累56例(28.6%),按解剖部位分为近侧胃癌(proximalgastriccancer,PGC)组和远侧胃癌(distalgastriccancer,DGC)组。观察胃癌侵犯GBA的CT表现特征,比较PGC组和DGC组胃癌侵犯GBA的出现率差异。结果56例中,有46例表现为GBA内软组织肿块,10例表现为结节状淋巴结。胃癌侵犯GBA病例的CT征象有:GBA增宽,胃壁与膈肌之间的薄层脂肪间隙中断或消失;GBA内可见不均匀强化的软组织密度肿块或类圆形淋巴结;左膈脚及胃膈韧带不规则增厚并与肿瘤分界不清;膈下腹膜后间隙淋巴结肿大。PGC组中,胃癌侵犯GBA的出现率为70.0%(42/60),而在DGC组仅为10.3%(14/136),两者间差异有显著性意义(P=0.025)。结论PGC侵犯GBA的出现率高于DGC。胃癌侵犯GBA有一定的CT表现特征。多排螺旋CT在术前评价GBA受侵和淋巴结转移方面具有重要价值。

Objective To study the CT features of bare area involvement in gastric carcinoma and their anatomic-pathological basis, and to evaluate the role of multi-detector CT in the diagnosis of bare area involvement. Methods In 196 consecutive gastric carcinoma cases, 56 were found bare area involvement and divided into proximal gastric carcinoma (PGC) group and distal gastric carcinoma (DGC) group according to anatomic position of primary tumor. CT images and incidence of gastric bare area (GBA) involvement in the PGC group were observed and compared with those of DGC group. Results The lesion appeared as nodule or mass in bare area in 46 cases and as metastatic lymphadenopathy in 10 cases. CT features of GBA involvement included: ① widening of gastric bare area and blurring or obliteration of the thin fat strip between gastric wall and diaphragm; ② irregular mass with heterogeneous enhancement or round lymph nodes in GBA; ③ irregular thickening of left diaphragmatic crus or gastrophrenic ligament with blurring border to the mass; ④ other metastatic lymph nodes in subphrenic extroperitoneal space. The incidence of GBA involvement in PGC group was 70.0%(42/60), significantly difference from those in DGC group (10.3%,14/136) ,P=0.025. Conclusion The incidence of GBA involvement in PGC group is significantly higher than those in DGC group. Multi-detector CT is very useful for preoperative imaging evaluation of bare area involvement and lymphatic spread.