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肾上皮样血管平滑肌脂肪瘤(epithelioid angiomyolipoma,EAML)是一种具有恶性倾向的间叶性肿瘤,在既往研究中,其上皮样细胞占比从5%~100%不等,且上皮样细胞占比越高,恶性倾向越明显[1-3]。2016年世界卫生组织泌尿系统和男性生殖器官肿瘤分类标准[4]中明确定义肾EAML中上皮样细胞占比应≥80%。笔者将EAML以外含上皮样成分的血管平滑肌脂肪瘤(angiomyolipoma,AML)称为类上皮样AML(尚未有文献明确指出如何命名)。目前,肾EAML术前影像学的准确诊断仍然存在困难,其常被误诊为其他类型的肾AML或肾透明细胞癌,部分患者因诊治不当出现复发和(或)远处转移[2]。本研究回顾性分析原病理诊断为肾EAML的患者资料,将所有病灶组织的标本重新切片、染色后镜下观察,并以此为基础,对比分析肾EAML和类上皮样AML的CT影像表现与上皮样细胞占比的关系,探讨肾EAML的CT影像特征和诊断要点,为临床诊治提供更可靠的CT影像信息。
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镜下肿瘤组织主要见不同占比的血管、梭形平滑肌细胞、脂肪细胞、上皮样细胞。根据上皮样细胞占载玻片总面积的百分比不同分为以下2组。(1)肾EAML组:上皮样细胞占80%~100%,均数为86.7%,细胞呈圆形或多边形,呈巢状、片状排列,部分核不规则,具有核异型性,梭形平滑肌细胞和脂肪细胞占比较少(图1中A);(2)类上皮样AML组:上皮样细胞占5%~50%,均数为23.6%,其他多为梭形平滑肌细胞和脂肪细胞(图1中B)。由表1可知,肾EAML组上皮样细胞占比明显高于类上皮样AML组,且肾EAML组上皮样细胞核异型程度高于类上皮样AML组。
图 1 肾EAML患者(女性,38岁)左肾(A)和类上皮样AML患者(男性,59岁)右肾(B)的病理图
Figure 1. Pathological pictures of left kidney of a patient(female,38 years old)with renal epithelioid angiomyolipoma and right kidney of a patient(male,59 years old)with epithelioid-like angiomyolipoma
组别 脂肪细胞占比(%) 梭形平滑肌细胞占比(%) 上皮样细胞占比(%) 上皮样细胞核异型程度(例) 轻 中 重 肾EAML组(n=15) 2.9 10.4 86.7 3 9 3 类上皮样AML组(n=7) 25.7 50.7 23.6 4 3 0 注:表中,EAML:上皮样血管平滑肌脂肪瘤;AML:血管平滑肌脂肪瘤 表 1 2组患者病理学表现的比较
Table 1. Comparison of pathological findings in two groups of patients
肾EAML组患者共15例,均为单发病灶,其中男性2例、女性13例,中位年龄41(22~72)岁,5例因体检发现,9例因腰痛就诊,1例因腰痛伴血尿就诊。类上皮样AML组患者共7例,均为单发病灶,其中男性2例、女性5例,中位年龄42(37~64)岁,4例因体检入院,3例因肿瘤破裂出血急诊入院。
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肾EAML患者左肾CT图像见图2,肾EAML患者的肿瘤大,无脂肪(图2中A),有坏死液化(图2中B~C),皮质期强化较轻微(图2中B),呈“快进慢出”的强化模式(图2中D)。右肾类上皮样AML患者CT图像见图3,类上皮样AML患者的肿瘤小,有脂肪(图3中A),无坏死液化(图3中B~C),皮质期强化较明显(图3中B),呈“快进快出”的强化模式(图3中D)。由表2可知,2组间肿瘤长径、坏死液化、肿瘤内脂肪和强化模式的差异有统计学意义(均P<0.05)。2组间不同病灶形态,不同CT平扫密度,有无出血和粗大血管的差异无统计学意义(均P>0.05)。
图 2 肾EAML患者(女性,38岁)左肾CT图
Figure 2. CT images of left kidney of a patient(female,38 years old)with renal epithelioid angiomyolipoma
CT征象 肾EAML组
(n=15)类上皮样
AML组(n=7)检验值 P值 肿瘤长径(cm) 8.40±4.26 4.90±1.84 t=2.66 0.015 病灶形态[例(%)] − 0.343 不规则形 4(26.7%) 4(57.1%) 类圆形 11(73.3%) 3(42.9%) CT平扫密度[例(%)] − 1.000 等或稍高密度 15(100.0%) 7(100.0%) 低或稍低密度 0(0) 0(0) 坏死液化[例(%)] − 0.020 有 11(73.3%) 1(14.3%) 无 4(26.7%) 6(85.7%) 出血[例(%)] − 0.343 有 4(26.7%) 4(57.1%) 无 11(73.3%) 3(42.9%) 肿瘤内脂肪[例(%)] − 0.002 有 2(13.3%) 6(85.7%) 无 13(86.7%) 1(14.3%) 强化模式[例(%)] − 0.017 快进快出 3(20.0%) 6(85.7%) 快进慢出 11(73.3%) 1(14.3%) 渐进强化 1(6.7%) 0(0) 粗大血管[例(%)] − 1.000 有 12(80.0%) 6(85.7%) 无 3(20.0%) 1(14.3%) 注:表中,CT:计算机体层摄影术;EAML:上皮样血管平滑肌脂肪瘤;AML:血管平滑肌脂肪瘤;−:Fisher's确切概率法,无检验值 表 2 2组患者CT征象的比较
Table 2. Comparison of CT findings in two groups of patients
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由表3可知,2组间肿瘤平扫CT值、增强皮质期及髓质期的CT值、髓质期强化比值的差异均无统计学意义(均P>0.05),而皮质期强化比值的差异有统计学意义(Z=−3.56,P<0.001)。
组别 CT值( )$\bar x \pm s$ 强化比值[M(P25,P75)] 平扫 增强皮质期 增强髓质期 皮质期 髓质期 肾EAML(n=15) 46.3±4.19 106.3±38.06 93.8±29.33 0.61(0.56,0.67) 0.52(0.43,0.55) 类上皮样AML(n=7) 43.3±3.20 119.0±16.97 82.1±11.39 0.96(0.92,0.97) 0.53(0.52,0.54) 检验值 t=1.70 t=−1.08 t=1.01 Z=−3.56 Z=−0.89 P值 0.105 0.293 0.327 <0.001 0.394 注:表中,CT:计算机体层摄影术;EAML:上皮样血管平滑肌脂肪瘤;AML:血管平滑肌脂肪瘤 表 3 2组患者各期CT值及强化比值的比较
Table 3. Comparison of CT value and enhancement ratio of two groups of patients
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由表4可知,皮质期强化比值≤0.73时肾EAML的诊断效能最高[AUC=0.981(0.813~1.000),Youden=0.87];Youden指数由高到低依次为肿瘤内无脂肪、“快进慢出”强化模式、有坏死液化、肿瘤长径>8 cm。
CT征象 灵敏度(%) 特异度(%) AUC(95%CI) 阳性预测值(%) 阴性预测值(%) Youden指数 临界值及标准 肿瘤长径 46.7 100.0 0.738(0.509~0.900) 100.0 46.7 0.47 >8 cm 坏死液化 73.3 85.7 0.795(0.571~0.935) 91.7 60.0 0.59 有 肿瘤内脂肪 86.7 85.7 0.862(0.649~0.970) 92.9 75.0 0.72 无 强化模式 80.0 85.7 0.833(0.615~0.956) 92.3 66.7 0.66 快进慢出 皮质期强化比值 86.7 100.0 0.981(0.813~1.000) 100.0 77.8 0.87 ≤0.73 注:表中,EAML:上皮样血管平滑肌脂肪瘤;AML:血管平滑肌脂肪瘤;CT:计算机体层摄影术;AUC:曲线下面积;CI:可变区间 表 4 22例肾EAML与7例类上皮样AML患者CT征象诊断效能的比较
Table 4. Comparison of the diagnostic efficacy of CT findings in 22 patients with renal epithelioid angiomyolipoma and 7 patients with epithelioid-like angiomyolipoma
肾上皮样与类上皮样血管平滑肌脂肪瘤CT影像与病理学表现的对照分析
Comparative analysis of CT images and pathological findings of renal epithelioid angiomyolipoma and epithelioid-like angiomyolipoma
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摘要:
目的 探讨肾上皮样血管平滑肌脂肪瘤(EAML)与类上皮样血管平滑肌脂肪瘤(AML)的CT和病理学特征。 方法 回顾性分析2008年6月至2018年10月在南方医科大学顺德医院(佛山市顺德区第一人民医院)和佛山市第一人民医院经病理诊断为肾EAML的22例患者的资料,其中男性4例、女性18例,中位年龄48.9(22~72)岁。将所有病灶组织的标本重新切片、染色后镜下观察,并根据此次观察的标本中上皮样成分占比,分为肾EAML组和类上皮样AML组。对比分析2组患者CT图像上的肿瘤长径、形态、坏死液化、出血、肿瘤内脂肪、强化模式等CT征象并测量各期CT值,计算皮质期和髓质期的强化比值,并用皮质期强化比值反映皮质期强化程度。2组间的比较采用独立样本t检验、Mann-Whitney U检验和Fisher's确切概率法。 结果 肾EAML组(15例)的上皮样细胞占86.7%,细胞呈圆形或多边形,呈巢状、片状排列,部分核不规则,具有核异型性;类上皮样AML组(7例)的上皮样细胞占23.6%,其他多为梭形平滑肌细胞和脂肪细胞。肾EAML组和类上皮样AML组在肿瘤长径[(8.40±4.26) cm对(4.90±1.84) cm]、坏死液化[73.3%(11/15)对14.3%(1/7)]、肿瘤内脂肪[86.7%(13/15)对14.3%(1/7)]、强化模式[73.3%(11/15)对14.3%(1/7)]的差异均有统计学意义(t=2.66,Fisher's确切概率法,均P<0.05);在皮质期增强CT强化比值的差异有统计学意义[0.61(0.56, 0.67)对0.96(0.92, 0.97),Z=−3.56,P<0.001],且临界值≤0.73时的诊断效能最高[曲线下面积=0.981(0.813~1.000),Youden=0.87],Youden指数由高到低依次为肿瘤内无脂肪、“快进慢出”强化模式、有坏死液化、肿瘤长径>8 cm。 结论 肾EAML具有特征性CT征象,尤其当皮质期强化比值≤0.73时,应高度怀疑肾EAML。 -
关键词:
- 体层摄影术,X线计算机 /
- 病理学 /
- 肾上皮样血管平滑肌脂肪瘤
Abstract:Objective To investigate the CT and pathological features of renal epithelioid angiomyolipoma (EAML) and epithelioid-like angiomyolipoma (AML). Methods Retrospectively collected data on 22 cases of EAML diagnosed by initial pathology in the Shunde Hospital of the Southern Medical University (the First People's Hospital of Shunde in Foshan City) and the First People's Hospital of Foshan from June 2008 to October 2018, including 4 males and 18 females with an average age of 48.9 years (ranging from 22 years to 72 years). The specimens of all lesions were resliced, stained, observed under microscope, and divided into the EAML and epithelioid-like AML groups according to their proportion of epithelioid components. A comparative analysis of CT signs, such as lesion diameter, morphology, liquid necrosis, hemorrhage, fat, and enhanced mode, on the CT images in both groups was performed. The CT values of each phase were measured, and the enhancement ratio of the cortical and medulla phases, which can reflect the degree of enhancement in each phase, was calculated. Independent sample t test, Mann-Whitney U test, and Fisher's exact probability method were used to compare the two groups. Results The epithelioid cells in the renal EAML group (15 cases) accounted for 86.7%, and the cells were round or polygonal, arranged in nests and sheets, and some nuclei were irregular and atypia. The epithelioid cells in the epithelioid-like AML group (7 cases) accounted for 23.6%, and the rest part were mostly spindle-shaped smooth muscle cells and adipocytes. The renal EAML group and the epithelioid-like AML group had significant differences in the lesion length ((8.40±4.26) cm vs. (4.90±1.84) cm), liquid necrosis (73.3%(11/15) vs. 14.3% (1/7)), fat (86.7%(13/15) vs. 14.3%(1/7)), and enhancement pattern (73.3%(11/15) vs. 14.3%(1/7)) (t=2.66; Fisher's exact probability method; all P<0.05). The cortical phase enhancement ratio was statistically significant (0.61 (0.56, 0.67) vs. 0.96 (0.92, 0.97), Z=−3.56, P<0.001), and the diagnosis efficiency was the highest when the cutoff value was ≤0.73 (area under curve =0.981 (0.813−1.000), Youden=0.87). Youden index of fat-free, "fast-in and slow-out" intensive mode, liquid necrosis, and tumor length >8 cm in order from high to low. Conclusions EAML has characteristic CT signs especially when the cortical phase enhancement ratio is ≤0.73. In this case, EAML is highly suspected to be possible. -
Key words:
- Tomography, X-ray computed /
- Pathology /
- Renal epithelioid angiomyolipoma
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表 1 2组患者病理学表现的比较
Table 1. Comparison of pathological findings in two groups of patients
组别 脂肪细胞占比(%) 梭形平滑肌细胞占比(%) 上皮样细胞占比(%) 上皮样细胞核异型程度(例) 轻 中 重 肾EAML组(n=15) 2.9 10.4 86.7 3 9 3 类上皮样AML组(n=7) 25.7 50.7 23.6 4 3 0 注:表中,EAML:上皮样血管平滑肌脂肪瘤;AML:血管平滑肌脂肪瘤 表 2 2组患者CT征象的比较
Table 2. Comparison of CT findings in two groups of patients
CT征象 肾EAML组
(n=15)类上皮样
AML组(n=7)检验值 P值 肿瘤长径(cm) 8.40±4.26 4.90±1.84 t=2.66 0.015 病灶形态[例(%)] − 0.343 不规则形 4(26.7%) 4(57.1%) 类圆形 11(73.3%) 3(42.9%) CT平扫密度[例(%)] − 1.000 等或稍高密度 15(100.0%) 7(100.0%) 低或稍低密度 0(0) 0(0) 坏死液化[例(%)] − 0.020 有 11(73.3%) 1(14.3%) 无 4(26.7%) 6(85.7%) 出血[例(%)] − 0.343 有 4(26.7%) 4(57.1%) 无 11(73.3%) 3(42.9%) 肿瘤内脂肪[例(%)] − 0.002 有 2(13.3%) 6(85.7%) 无 13(86.7%) 1(14.3%) 强化模式[例(%)] − 0.017 快进快出 3(20.0%) 6(85.7%) 快进慢出 11(73.3%) 1(14.3%) 渐进强化 1(6.7%) 0(0) 粗大血管[例(%)] − 1.000 有 12(80.0%) 6(85.7%) 无 3(20.0%) 1(14.3%) 注:表中,CT:计算机体层摄影术;EAML:上皮样血管平滑肌脂肪瘤;AML:血管平滑肌脂肪瘤;−:Fisher's确切概率法,无检验值 表 3 2组患者各期CT值及强化比值的比较
Table 3. Comparison of CT value and enhancement ratio of two groups of patients
组别 CT值( )$\bar x \pm s$ 强化比值[M(P25,P75)] 平扫 增强皮质期 增强髓质期 皮质期 髓质期 肾EAML(n=15) 46.3±4.19 106.3±38.06 93.8±29.33 0.61(0.56,0.67) 0.52(0.43,0.55) 类上皮样AML(n=7) 43.3±3.20 119.0±16.97 82.1±11.39 0.96(0.92,0.97) 0.53(0.52,0.54) 检验值 t=1.70 t=−1.08 t=1.01 Z=−3.56 Z=−0.89 P值 0.105 0.293 0.327 <0.001 0.394 注:表中,CT:计算机体层摄影术;EAML:上皮样血管平滑肌脂肪瘤;AML:血管平滑肌脂肪瘤 表 4 22例肾EAML与7例类上皮样AML患者CT征象诊断效能的比较
Table 4. Comparison of the diagnostic efficacy of CT findings in 22 patients with renal epithelioid angiomyolipoma and 7 patients with epithelioid-like angiomyolipoma
CT征象 灵敏度(%) 特异度(%) AUC(95%CI) 阳性预测值(%) 阴性预测值(%) Youden指数 临界值及标准 肿瘤长径 46.7 100.0 0.738(0.509~0.900) 100.0 46.7 0.47 >8 cm 坏死液化 73.3 85.7 0.795(0.571~0.935) 91.7 60.0 0.59 有 肿瘤内脂肪 86.7 85.7 0.862(0.649~0.970) 92.9 75.0 0.72 无 强化模式 80.0 85.7 0.833(0.615~0.956) 92.3 66.7 0.66 快进慢出 皮质期强化比值 86.7 100.0 0.981(0.813~1.000) 100.0 77.8 0.87 ≤0.73 注:表中,EAML:上皮样血管平滑肌脂肪瘤;AML:血管平滑肌脂肪瘤;CT:计算机体层摄影术;AUC:曲线下面积;CI:可变区间 -
[1] Brimo F, Robinson B, Guo C, et al. Renal epithelioid angiomyolipoma with atypia: a series of 40 cases with emphasis on clinicopathologic prognostic indicators of malignancy[J]. Am J Surg Pathol, 2010, 34(5): 715−722. DOI: 10.1097/PAS.0b013e3181d90370. [2] Nese N, Martignoni G, Fletcher CD, et al. Pure epithelioid PEComas (so-called epithelioid angiomyolipoma) of the kidney: a clinicopathologic study of 41 cases: detailed assessment of morphology and risk stratification[J]. Am J Surg Pathol, 2011, 35(2): 161−176. DOI: 10.1097/PAS.0b013e318206f2a9. [3] Lei JH, Liu LR, Wei Q, et al. A four-year follow-up study of renal epithelioid angiomyolipoma: a multi-center experience and literature review[J/OL]. Sci Rep, 2015, 5: 10030[2020-02-28]. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4419536. DOI: 10.1038/srep10030. [4] Martignoni G, Reuter VE, Fletcher C, et al. Epithelioid angiomyolipoma of World Health Organization classification of tumours of the urinary system and male genital organs[M]. Lyon: IARC Press, 2016: 65−66. [5] 康钦钦, 马超, 张火俊, 等. 肾脏乏脂肪血管平滑肌脂肪瘤与透明细胞癌的高分辨螺旋CT特征分析[J]. 中华泌尿外科杂志, 2013, 34(10): 732−737. DOI: 10.3760/cma.j.issn.1000-6702.2013.10.003.
Kang QQ, Ma C, Zhang HJ, et al. Analysis of the characteristics of minimal fat renal angiomyolipoma and clear cell renal carcinoma in high resolution multi-slice spiral CT[J]. Chin J Urol, 2013, 34(10): 732−737. DOI: 10.3760/cma.j.issn.1000-6702.2013.10.003.[6] 沈江潮, 杨建峰. 肾乏脂性血管平滑肌脂肪瘤在MSCT腹部常规双期增强扫描中的强化特征分析[J]. 中国临床医学影像杂志, 2015, 26(7): 491−494.
Shen JC, Yang JF. Enhancement characteristics of renal angiomyolipoma with minimal fat on routine biphasic abdominal MSCT[J]. J Chin Clin Med Imaging, 2015, 26(7): 491−494.[7] Thway K, Fisher C. PEComa: morphology and genetics of a complex tumor family[J]. Ann Diagn Pathol, 2015, 19(5): 359−368. DOI: 10.1016/j.anndiagpath.2015.06.003. [8] Ebele JN, Sauter G, Epstein JI, et al. World Health Organization classification of tumours. Pathology and genetics of tumours of the urinary system and male genital organs[M]. Lyon: IARC Press, 2004: 64−69. [9] Cui L, Zhang JG, Hu XY, et al. CT imaging and histopathological features of renal epithelioid angiomyolipomas[J]. Clin Radiol, 2012, 67(12): e77−e82. DOI: 10.1016/j.crad.2012.08.006. [10] Zhong Y, Shen YG, Pan JJ, et al. Renal epithelioid angiomyolipoma: MRI findings[J]. Radiol Med, 2017, 122(11): 814−821. DOI: 10.1007/s11547-017-0788-9. [11] 郭锐, 康素海, 钟燕, 等. 肾上皮样与非上皮样血管平滑肌脂肪瘤磁共振影像表现与鉴别诊断[J]. 中华医学杂志, 2018, 98(45): 3701−3704. DOI: 10.3760/cma.j.issn.0376-2491.2018.45.014.
Guo R, Kang SH, Zhong Y, et al. Magnetic resonance imaging findings and differential diagnosis of renal epithelioid angiomyolipoma comparing with renal no-epithelioid angiomyolipoma[J]. Natl Med J China, 2018, 98(45): 3701−3704. DOI: 10.3760/cma.j.issn.0376-2491.2018.45.014.[12] Zheng S, Bi XG, Song QK, et al. A suggestion for pathological grossing and reporting based on prognostic indicators of malignancies from a pooled analysis of renal epithelioid angiomyolipoma[J]. Int Urol Nephrol, 2015, 47(10): 1643−1651. DOI: 10.1007/s11255-015-1079-9. [13] Jinzaki M, Silverman SG, Akita H, et al. Renal angiomyolipoma: a radiological classification and update on recent developments in diagnosis and management[J]. Abdom Imaging, 2014, 39(3): 588−604. DOI: 10.1007/s00261-014-0083-3. [14] 胡晓云, 方向明, 胡春洪, 等. 肾上皮样血管平滑肌脂肪瘤的CT表现[J]. 中华放射学杂志, 2010, 44(10): 1066−1068. DOI: 10.3760/cma.j.issn.1005-1201.2010.10.013.
Hu XY, Fang XM, Hu CH, et al. CT features of renal epithelioid angiomyolipomas[J]. Chin J Radiol, 2010, 44(10): 1066−1068. DOI: 10.3760/cma.j.issn.1005-1201.2010.10.013.[15] Cong XY, Zhang J, Xu XJ, et al. Renal epithelioid angiomyolipoma: magnetic resonance imaging characteristics[J]. Abdom Radiol (NY), 2018, 43(10): 2756−2763. DOI: 10.1007/s00261-018-1548-6. [16] 贺新华, 丁玉芹, 陈亮, 等. 肾脏乏脂肪血管平滑肌脂肪瘤的临床病理及CT表现[J]. 放射学实践, 2014, 29(6): 673−676. DOI: 10.13609/j.cnki.1000-0313.2014.06.023.
He XH, Ding YQ, Chen L, et al. Clinical, pathological and CT features of lipid-poor renal angiomyolipoma[J]. Radiol Pract, 2014, 29(6): 673−676. DOI: 10.13609/j.cnki.1000-0313.2014.06.023.[17] 丁玉芹, 于泳, 罗荣奎, 等. 多元Logistic回归分析CT征象鉴别乏脂肪血管平滑肌脂肪瘤和肾透明细胞癌的价值[J]. 临床放射学杂志, 2019, 38(3): 495−499. DOI: 10.13437/j.cnki.jcr.2019.03.032.
Ding YQ, Yu Y, Luo RK, et al. Value of multivariate Logistic regression analysis of CT features in the differential diagnosis of lipid-poor angiomyolipoma and clear cell renal cell carcinoma[J]. J Clin Radiol, 2019, 38(3): 495−499. DOI: 10.13437/j.cnki.jcr.2019.03.032.