MSCT诊断胰腺无功能性囊性神经内分泌肿瘤

目的探讨胰腺无功能性囊性神经内分泌肿瘤(NF-CNETP)的MSCT表现。方法回顾性分析10例经手术病理证实的NF-CNETP的MSCT表现,对照病理进行分析。结果 10例NF-CNETP中,位于胰头5例,胰尾4例,同时位于胰体尾部1例;肿瘤最大径2.5~6.2cm。10例肿瘤均边界清楚,其中9例见完整包膜。平扫肿瘤密度不均匀,实性囊壁呈等或稍低密度,10例中2例可见钙化。增强扫描动脉期9例呈明显环状不均匀强化,1例含壁结节者明显强化,门静脉期均呈持续性强化。肿瘤囊壁动脉期平均CT值为(128.00±62.62)HU,门静脉期为(132.40±44.66)HU。4例胰管轻度扩张。1例胰周淋巴结转移。6例接受能谱CT双能扫描,肿瘤囊壁动脉期及门静脉期的碘浓度值与腹主动脉的碘浓度值进行标准化后分别为0.40±0.16、0.79±0.22。结论 NF-CNETP的MSCT强化方式及包膜显示具有一定特征性,对诊断与鉴别诊断有一定意义。

MSCT in diagnosis of non-functioning cystic neuroendocrine tumors of pancreas

Objective To investigate MSCT features of non-functioning cystic neuroendocrine tumors of pancreas (NF-CNETP). Methods MSCT features of 10 patients with NF-CNETP proved by pathology were retrospectively reviewed and compared with pathological results. Results Among 10 patients, 5 tumors located in pancreatic head, 4 in the tail, and 1 in both pancreatic body and tail. The tumor size ranged from 2.5 cm to 6.2 cm. All tumors had well-defined contours, and 9 tumors showed complete capsules. On plain CT, the lesions showed heterogeneous density with slightly low density or isodensity of solid cyst wall. Calcifications were found in 2 cases. On enhanced CT, 9 tumors showed markedly ringed enhancement in arterial phase (AP), and the other 1 manifested enhanced mural nodule. All lesions showed continuous enhancement in portal venous phase (PP). CT value of cyst wall was (128.00±62.62)HU in AP and (132.40±44.66)HU in PP. Pancreatic duct in 4 patients had slight dilatation, and 1metastasis of peripancreatic lymph nodes was found. In 6 patients who underwent dual energy CT spectral imaging, iodine concentrations (IC) of lesions were measured and normalized to abdominal aorta to obtain normalized IC (nIC). The nIC values were 0.40±0.16 in AP and 0.79±0.22 in PP. Conclusion The enhancement pattern and appearance of capsule for NF-CNETP in MSCT play an important role in diagnosis and differential diagnosis of NF-CNETP.