胰腺实性-假乳头状瘤的CT诊断和鉴别诊断

CT diagnosis of solid-pseudopapillary tumors of the pancreas

目的 描述胰腺实性 假乳头状瘤的CT表现 ,探讨CT对该肿瘤的诊断价值。方法回顾分析经手术、病理证实的 11例胰腺实性 假乳头状瘤的CT表现和诊断。结果 ( 1)肿瘤内有实性和囊性结构 ,CT平扫实性结构呈低或等密度 ,造影后动脉期呈轻度强化 ,门静脉期呈明显强化 ,囊性部分在增强前后扫描均呈低密度。 ( 2 )囊实性结构比例相仿的肿瘤 7例 ,囊性结构为主者 3例 ,其CT表现分别为囊实部分相间分布或实质部分呈附壁结节。 ( 3)实性结构为主的肿瘤 1例 ,其CT表现为囊性部分位于包膜下。 ( 4)肿瘤绝大多数来源于胰腺 ,呈圆形、椭圆形 ,多有完整包膜 ,增强后强化明显 ,与胰腺分界清晰。 ( 5 )不伴有胆总管和胰管扩张。 ( 6 ) 8例术前诊断为良性、3例诊断为低度恶性肿瘤。结论 胰腺实性 假乳头状瘤CT表现有一定特征 ,且CT诊断有其重要价值 ,需与黏液性或浆液性囊腺瘤、囊腺癌、胰腺癌囊变、胰性假性囊肿等进行鉴别。

Objective To study the CT manifestations of the solid-pseudopapillary tumors of pancreas (SPTP) and to explore the CT diagnostic value. Methods CT features of eleven patients with pathologically proved SPTP were retrospectively analyzed. Results (1) There were solid and cystic structures within the neoplasm, the solid portions demonstrated hypo- or iso-attenuation on pre-contrast CT, and slight enhancement in the arterial phase and marked enhancement in the portal venous phase on post-contrast CT scan. The cystic portions appeared hypo-attenuation on both pre- and post-contrast views. (2) 7 tumors were composed of similar proportions of solid and cystic parts, and 3 tumors were mainly composed of cystic parts. Their CT findings were solid and cystic alternative distributions, and cystic portions with mural nodules, respectively. (3) The predominant solid tumor was found in 1 case with cystic portions under the capsule. (4) Most tumors occurred in the pancreas, presenting as round or oval in shape, and were completely encapsulated and marked enhanced with well-defined margins on post-contrast images. (5) There was no associated dilatation of the common bile duct or pancreatic duct. (6) 8 tumors were diagnosed as benign and 3 as low-grade malignant preoperatively. Conclusion The CT characteristic findings of SPTP might be of great value for the diagnosis. SPTP should be differentiated from mucous cystadenoma, mucous cystcarcinoma, nonfunctioning tumor, and pseudo-cyst of the pancreas.