Sato Motohiro, Okumura Toshiyuki, Kaito Keiko, Kiyoshima Moriyuki, Asato Yuji, Uchiumi Keiko, Iijima Hiroaki, Hashimoto Ikuta, Kaburagi Takayuki, Amemiya Ryuta
Department of Radiology, Ibaraki Prefectural Central Hospital, 6528 Koibuchi, Kasama, Ibaraki, 309-1793, Japan.
Ann Nucl Med. 2009 Jan;23(1):49-57. doi: 10.1007/s12149-008-0205-5. Epub 2009 Feb 11.
The objective of this study was to assess the ability to detect pancreatic metastasis of lung cancer and to clarify the degree of fluorodeoxyglucose (FDG) accumulation and computed tomography (CT) characteristics of pancreatic metastasis from lung cancer.
A total of 573 patients (415 men and 158 women) with lung cancer were retrospectively evaluated. All patients underwent FDG-positron emission tomography (PET)/CT with contrast-enhanced CT for first=stage (313 patients; initial study group) or follow-up study (260 patients; follow-up study group). A lesion was regarded as positive for metastasis on the basis of visual judgment of the degree of increased metabolism by two experienced and independent interpreters, supported by semiquantitative evaluation on the basis of calculation of the maximum standardized uptake value (SUV(max)).
Abnormal accumulations in the pancreas were detected in 5 of 313 patients (1.60%) in the initial study group, and 6 of 260 patients (2.31%) in the follow-up study group. Seven of these patients had adenocarcinoma, three had small cell carcinoma, and the rest had large cell endocrine carcinoma. Tumor sizes (longitudinal diameter), measured by CT, of these 11 patients ranged from 6 mm to 52 mm (mean +/- SD 8.3 mm +/- 11.9 mm), and SUV(max) for 1 h ranged from 3.37 to 11.1 (mean +/- SD 6.12 +/- 2.43). Three of these pancreatic lesions were difficult to determine by routine transaxial images, and detection was obvious only by thin-slice images or multiplanar reconstruction images. Contrast-enhanced CT showed gradual fill-in from the peripheral portion to the center. In addition, 10 of 11 cases did not show main pancreatic duct dilatation even if the tumor size was large.
Metastases to the pancreas in lung cancer patients are not so rare and radiologists first have an important role to detect the pancreatic mass and then suggest to metastasis as the likely diagnosis. For this purpose, FDG-PET/CT has an advantage in depicting unsuspected pancreatic metastasis from lung cancer, particularly that which is not detected by CT alone.
本研究旨在评估检测肺癌胰腺转移的能力，并阐明肺癌胰腺转移灶的氟脱氧葡萄糖（FDG）摄取程度及计算机断层扫描（CT）特征。
对573例肺癌患者（415例男性和158例女性）进行回顾性评估。所有患者均接受了FDG正电子发射断层扫描（PET）/CT检查，并结合增强CT进行首次分期检查（313例患者；初始研究组）或随访研究（260例患者；随访研究组）。由两名经验丰富且独立的解读人员根据代谢增高程度的视觉判断，并基于最大标准化摄取值（SUV(max)）计算进行半定量评估，将病灶判定为转移阳性。
初始研究组313例患者中有5例（1.60%）在胰腺发现异常摄取，随访研究组260例患者中有6例（2.31%）出现异常摄取。这些患者中7例为腺癌，3例为小细胞癌，其余为大细胞内分泌癌。这11例患者经CT测量的肿瘤大小（纵径）为6 mm至52 mm（平均±标准差8.3 mm±11.9 mm），1小时的SUV(max)范围为3.37至11.1（平均±标准差6.12±2.43）。其中3个胰腺病灶通过常规横轴位图像难以确定，仅通过薄层图像或多平面重建图像才能明显显示。增强CT显示从周边部分向中心逐渐填充。此外，11例中有10例即使肿瘤较大也未显示主胰管扩张。
肺癌患者发生胰腺转移并非罕见，放射科医生首先在检测胰腺肿块方面发挥重要作用，然后提示转移可能是诊断结果。为此，FDG-PET/CT在显示肺癌未被怀疑的胰腺转移方面具有优势，尤其是单独CT未检测到的转移灶。
