摘要目的：探讨胰腺癌（ PC）淋巴结转移的多层螺旋CT（ MSCT）影像学特征。方法选取经病理确诊为PC且有淋巴结转移的患者30例，术前均进行MSCT胰腺增强扫描。以日本胰腺病学会2002年制定的第5版TNM分期为淋巴结分组标准，分析转移淋巴结的部位、最大短轴径（ MSAD）、淋巴结密度、强化、内部坏死及融合情况。结果病理诊断转移淋巴结63枚，影像诊断转移淋巴结53枚。胰头癌以第13组、第17组淋巴结转移率较高，胰体尾癌以第18组转移率较高。转移淋巴结MSAD为2～17 mm，平均（7．2±4．0）mm。按淋巴结大小分为MSAD＜5 mm组、5 mm～＜10 mm组和≥10 mm组，每组转移淋巴结分别为10枚、18枚和25枚。3组转移淋巴结的强化枚数随淋巴结的增大而减少，而内部坏死、融合枚数随淋巴结的增大而增加，差异均有统计学意义（P 值均＜0．05）。两两组间比较， MSAD＜5 mm组、5 mm～＜10 mm组强化淋巴结枚数显著多于≥10 mm组（7／10、11／18比2／25），融合淋巴结枚数显著少于≥10 mm组（0、2／18比22／25）；＜5 mm组边缘清晰淋巴结枚数显著多于≥10 mm组（6／10比5／25），内部坏死枚数显著少于≥10 mm组（2／10比18／25），差异均有统计学意义（P 值均＜0．05）。其余两两组间差异均无统计学意义。结论淋巴结不明显强化、内部坏死及融合是PC淋巴结转移的主要影像学特征，结合淋巴结密度不均匀、边缘模糊的特征更有助于诊断转移淋巴结。

abstractsObjective To discuss the MSCT imaging characteristics of metastatic lymph nodes in pancreatic cancer.Methods The MSCT images of 30 pancreatic cancer patients with metastatic lymph node confirmed by pathology were selected and all the patients underwent enhanced MSCT before surgery.The location, maximum short axis diameter ( MSAD) , sizes, density, enhancement, necrosis and fusion of the metastatic lymph nodes were analyzed using the 5th edition of TNM stage of Japan Pancreatic Society in 2002 as the standard.Results Sixty-three metastatic lymph nodes was pathologically diagnosed , while 53were diagnosed by MSCT.The metastatic lymph nodes most commonly occurred in group 13 and 17in pancreatic head cancer, while group 18 lymph node metastasis was more common in pancreatic body and tail cancer.The MSAD of metastatic lymph nodes was 2~17 mm with the average of (7.2 ±4.0)mm.All of metastatic lymph nodes were divided into MSAD <5 mm group, 5 mm~<10 mm group and ≥10 mm group based on their size.The number of metastatic lymph nodes of the three groups were 10, 18 and 25, respectively.The number of enhanced metastatic lymph nodes was decreased as the size increased, while the number of necrotic and fused lymph nodes was increased, which were statistically different (all P<0.05).Comparison between the&nbsp;two groups showed that the number of enhancement metastatic lymph nodes in MSAD <5 mm group and 5 mm~<10 mm group were more than that in ≥10 mm group ( 7/10 and 11/18 vs 2/25 ) .The number of fused lymph nodes in MSAD <5 mm group and 5 mm~<10 mm group were less than that in≥10 mm group (0 and 2/18 vs 22/25 ) .Clear edge metastatic lymph nodes were more in MSAD <5 mm group than that in≥10 mm group (6/10 vs 5/25).The number of necrotic metastatic lymph nodes in MSAD <5 mm group was less than that in ≥10 mm group(2 /10 vs 18/25).All the differences above were statistically significant ( all P<0.05), but no other significant differences were found between two groups.Conclusions The main imaging findings of metastatic lymph nodes in pancreatic cancer were unobvious enhancement, intratumoral necrosis and fusion.Heterogeneous density and unclear edge could benefit the diagnosis of metastatic lymph node.