小（≤ 20mm）胰腺腺癌：多期多层 CT 增强模式和次要征象分析。

Small (≤ 20 mm) pancreatic adenocarcinomas: analysis of enhancement patterns and secondary signs with multiphasic multidetector CT.

机构信息

Department of Radiology, Seoul National University College of Medicine, 28 Yongon-dong, Chongno-gu, Seoul 110-744, Korea.

出版信息

Radiology. 2011 May;259(2):442-52. doi: 10.1148/radiol.11101133. Epub 2011 Mar 15.

DOI:10.1148/radiol.11101133

PMID:21406627

Abstract

PURPOSE

To evaluate the enhancement patterns, prevalence of secondary signs, and histopathologic features of 20-mm-diameter or smaller pancreatic cancers seen on multiphasic multidetector computed tomographic (CT) images.

MATERIALS AND METHODS

This retrospective study was approved by the institutional review board; the requirement for informed consent was waived. From January 2002 through September 2009, the authors reviewed the clinical and imaging data of 130 consecutive patients (76 men, 54 women; mean age, 64.1 years; age range, 28-82 years) who had surgically proven 30-mm-diameter or smaller pancreatic cancers and underwent preoperative multidetector CT and 33 consecutive patients (17 men, 16 women; mean age, 65.1 years; age range, 48-84 years) who had histopathologically proven pancreatic cancer and underwent incidental multidetector CT before the diagnosis was rendered. Only pancreatic phase CT was performed in two patients, and only hepatic venous phase CT was performed in nine patients. Two radiologists in consensus classified the tumor attenuation as hyper-, iso-, or hypoattenuation during the pancreatic and hepatic venous phases. Accompanying secondary signs, temporal changes in tumor attenuation, and histopathologic findings also were analyzed. The Fisher exact test, χ(2) test, generalized estimating equation, and Student t test were used to compare the variables.

RESULTS

Seventy tumors were 20 mm or smaller, and 93 were 21-30 mm. Isoattenuating pancreatic cancers were more commonly observed among the 20-mm or smaller tumors (16 of 59, 27%) than among the 21-30-mm tumors (12 of 93, 13%) (P = .033). They were also more common among well-differentiated tumors (seven of 12, 58%) than among moderately differentiated (20 of 124, 16%) and poorly differentiated (one of 10, 10%) tumors (P = .001). The prevalence of secondary signs differed significantly according to tumor size (53 [76%] of 70 ≤20-mm tumors vs 92 [99%] of 93 21-30-mm tumors) (P < .001). The prevalence of secondary signs was high among isoattenuating pancreatic cancers (14 [88%] of 16 ≤20-mm tumors vs all 12 [100%] 21-30-mm tumors). Most of the isoattenuating tumors seen at prediagnostic CT were hypoattenuating after 6 months (100% [four of four] during pancreatic phase, 71% [five of seven] during hepatic venous phase).

CONCLUSION

The prevalence of isoattenuating pancreatic cancers differed significantly according to tumor size and cellular differentiation. Most small isoattenuating pancreatic cancers showed secondary signs.

SUPPLEMENTAL MATERIAL

http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11101133/-/DC1.

摘要

目的

评估多期多层 CT 图像上 20mm 或更小直径的胰腺癌的强化模式、次要征象的发生率和组织病理学特征。

材料与方法

本回顾性研究经机构审查委员会批准；无需患者知情同意。2002 年 1 月至 2009 年 9 月，作者对 130 例经手术证实的 30mm 或更小直径胰腺癌患者（76 例男性，54 例女性；平均年龄 64.1 岁；年龄范围 28-82 岁）的临床和影像学资料进行了回顾性分析，这些患者均接受了术前多层 CT 检查，还对 33 例经组织病理学证实的胰腺癌患者（17 例男性，16 例女性；平均年龄 65.1 岁；年龄范围 48-84 岁）的临床和影像学资料进行了回顾性分析，这些患者在诊断前接受了偶然的多层 CT 检查。只有 2 例患者仅进行了胰腺期 CT，9 例患者仅进行了肝静脉期 CT。两位放射科医生对胰腺期和肝静脉期肿瘤的衰减情况进行了共识分类，分别为高、等、低衰减。还分析了伴随的次要征象、肿瘤衰减的时间变化和组织病理学发现。采用 Fisher 确切检验、卡方检验、广义估计方程和 Student t 检验对变量进行比较。

结果

70 个肿瘤为 20mm 或更小，93 个肿瘤为 21-30mm。20mm 或更小的等密度肿瘤（16/59，27%）比 21-30mm 的肿瘤（12/93，13%）更常见（P =.033）。它们也更常见于分化良好的肿瘤（12/12，58%），而不是中等分化（20/124，16%）和低分化（1/10，10%）肿瘤（P =.001）。根据肿瘤大小，次要征象的发生率有显著差异（53/70（76%）≤20mm 肿瘤比 92/93（99%）21-30mm 肿瘤）（P <.001）。等密度胰腺肿瘤的次要征象发生率较高（16/16（88%）≤20mm 肿瘤比 12/12（100%）21-30mm 肿瘤）。在诊断前的 CT 上看到的大多数等密度肿瘤在 6 个月后表现为低衰减（4/4（100%）在胰腺期，7/7（100%）在肝静脉期）。