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肾脏淋巴瘤是一种少见的肾脏恶性肿瘤,根据侵犯形式分为原发性肾淋巴瘤(primary renal lymphoma, PRL))和继发性肾淋巴瘤(secondary renal lymphoma, SRL)。其中,PRL较罕见,SRL相对多见,占结外淋巴瘤的3%~8%,但其常规影像学表现并无特征性,可以表现为肾脏结节与肿物或肾脏肿胀,相对于肾脏其他肿瘤,在未知相关病史的情况下,即使是SRL也很容易被误诊与漏诊[1]。尤其是双肾弥漫性肿胀型病变,亦常见于一些肾脏免疫性疾病(renal immune disease, RID),且SRL和RID均可以累及多个组织器官,因此在未知相关病史或相关实验室检查不完善、不典型的情况下,两者很容易混淆。近年来,Arimoto等[2]认为,18F-FDG PET/CT对多种淋巴瘤的诊断和评估具有不可替代的优势,且已被作为多种淋巴瘤的评价标准。因此,我们回顾性分析SRL患者的PET/CT影像学表现,并与IgG4相关性肾病(IgG4-related kidney disease, IgG4-RKD)和肾抗中性粒细胞胞浆抗体相关性血管炎(anti-neutrophil cytoplasmic antibody-associated vasculitis, AAV)这2种易混淆的RID进行对比,以期提高对SRL诊断的准确率。
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SRL组、RID组与正常对照组3组间受检者年龄的比较[(50±15对60±10对55±10)岁],差异无统计学意义(F=1.801, P=0.183)。
SRL组和RID组患者主要表现为发热、乏力和腰部不适,其中1例IgG4-RKD、5例肾AAV和2例SRL患者肾功能受损。正常对照组受检者未见特殊不适,肾功能均正常。其他具体的临床资料见表1。
组别 年龄( ±s,岁)$\bar x$ 男/女
(例)血肌酐水平[M(Q1, Q3),μmol/L] 发热
[例(%)]腰部不适
[例(%)]血尿
[例(%)]蛋白尿
[例(%)]继发性肾淋巴瘤组
(n=12)50±15 7/5 80(50,105) 1(8) 6(50) 1(8) 6(50) 肾脏免疫性疾病组
(n=10)60±10 5/5 89(71,121) 7(70) 4(40) 5(50) 5(50) 正常对照组(n=10) 55±10 5/5 67(60,79) 0(0) 0(0) 0(0) 0(0) 注:血肌酐水平正常参考值为45~84 μmol/L 表 1 3组受检者的临床资料
Table 1. Clinical data of subjects in three groups
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12例SRL患者中,6例表现为肾脏弥漫性肿胀,其中4例累及双侧肾脏(图1,双侧肾脏弥漫性肿胀型SRL,确诊为弥漫大B细胞淋巴瘤),2例累及单侧肾脏;另6例为双侧肾脏多发结节与肿物型(图2,双侧肾脏多发结节型SRL,确诊为弥漫大B细胞淋巴瘤)。肾脏弥漫性肿胀型SRL可见两种不同的影像学表现:(1)4例表现为肾脏弥漫性不规则肿胀,结构大致正常,肾实质密度增高,密度尚均匀,轮廓欠规则,肾周筋膜增厚、粗糙,伴肾周软组织密度结节形成,其中2例双侧肾窦及双侧输尿管中上段亦可见受累,其内可见软组织密度灶,18F-FDG摄取异常增高。(2)2例表现为肾脏弥漫性肿胀,轮廓规则,结构完整,肾实质密度均匀,肾周筋膜未见异常,肾实质18F-FDG摄取异常增高。双肾多发结节与肿物型主要表现为肾实质内多发类圆形或不规则形结节或肿块,病灶最大径从数毫米至数厘米,部分相互融合,位于肾脏皮质或髓质,边界不清,呈等密度、低或略高密度,密度均匀。其中2例可见一侧肾脏内巨大软组织密度肿块,几乎占据全肾,轮廓不规则,正常结构显示欠清晰,肿块密度均匀,无明显坏死及钙化。所有肾脏受累病变18F-FDG摄取均异常增高。
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2例IgG4-RKD患者均为双侧肾脏受累,表现为双侧肾脏弥漫性肿胀型(图3),轮廓欠规则,结构尚完整,肾实质密度略增高,密度尚均匀,肾周筋膜、邻近壁腹膜增厚、粗糙。其中1例累及肾窦,其内可见软组织密度灶,并且伴肾周软组织结节形成。双侧肾实质、肾窦和肾周结节18F-FDG摄取异常增高。8例肾AAV患者亦均累及双肾,表现为双肾弥漫性肿胀型(图4),但与IgG4-RKD有所不同,其PET/CT图像可见双侧肾脏弥漫性肿胀,轮廓规则,边缘光滑,结构完整,肾实质密度均匀,肾周筋膜未见异常。受累肾实质18F-FDG摄取弥漫性增高,以肾皮质为著。
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健康受检者的双肾形态、结构、密度未见明显异常,18F-FDG主要分布于双侧肾盏肾盂内,双肾实质仅可见少量、均匀的放射性分布,肾实质与肾盂的放射性分布有较明显差异(图5)。
图 5 健康受检者(男性,60岁)的18F-FDG PET/CT显像图A为全身最大密度投影图,显示双侧肾盂、输尿管及膀胱内可见生理性18F-FDG分布,其余体部未见明显异常摄取;B为横断面PET/CT融合图,显示18F-FDG主要分布于双侧肾盏肾盂内,双肾实质仅可见少量、均匀的放射性分布,SUVmax=3.38,SUVratio=1.50;C为横断面CT图,显示双肾形态、结构及密度未见明显异常。FDG为氟脱氧葡萄糖;PET为正电子发射断层显像术;CT为计算机体层摄影术;SUVmax为最大标准化摄取值;SUVratio为正常肾皮质SUVmax/肝脏平均标准化摄取值的比值
Figure 5. 18F-FDG PET/CT image of healthy subject (male, 60 years old)
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SRL组患者肾外可见淋巴结与多个脏器组织(肺、心包、乳腺、子宫、卵巢、脾等)不同程度的受累,受累淋巴结肿大,部分融合,累及脏器瘤体密度均匀,无囊变坏死及出血钙化,受累病变18F-FDG摄取异常增高,其分布无明显规律性。
RID组中,2例IgG4-RKD患者均可见全身多发大致对称分布的增大淋巴结、双肺多发斑片与结节、双侧腮腺、颌下腺与泪腺弥漫性肿大伴多发结节,病灶18F-FDG摄取增高,考虑为肾外组织受累。2例肾AAV患者伴双肺多发斑片、结节影,其中1例伴鼻窦部软组织增厚,18F-FDG摄取均明显增高,考虑为肾外组织受累;另外1例伴中轴骨18F-FDG摄取弥漫性轻度增高,5例伴有脾18F-FDG摄取弥漫性轻度增高,3例伴腹腔及腹膜后多发小淋巴结,18F-FDG摄取轻度增高,考虑可能为炎症的反应性改变。
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对SRL组、RID组与正常对照组3组之间肾脏病变的SUVmax、SUVratio进行方差分析比较,结果显示,SRL组肾脏病变的SUVmax、SUVratio显著高于RID组(21.88±12.04对9.09±3.51、11.38±6.52对3.67±1.12),2组肾脏病变的SUVmax、SUVratio亦均显著高于正常对照组(SUVmax=3.23±0.39,SUVratio=1.47±0.25),且差异均有统计学意义(F=17.189、18.361,均P<0.001)。
SRL组与RID组肾外受累病变的18F-FDG摄取比较结果显示,SRL组肾外受累病变18F-FDG摄取SUVmax显著高于RID组(27.67±15.09对7.55±3.70),且差异有统计学意义(t=−3.889,P=0.001)。
18F-FDG PET/CT在继发性肾淋巴瘤与肾脏免疫性疾病鉴别诊断中的价值
Value of 18F-FDG PET/CT in the differentiation of secondary renal lymphoma and renal immune disease
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摘要:
目的 探讨18F-氟脱氧葡萄糖(FDG )PET/CT对继发性肾淋巴瘤(SRL)的诊断价值,并与肾脏免疫性疾病(RID)进行鉴别分析。 方法 回顾性分析2017年12月至2020年12月于天津市第一中心医院行18F-FDG PET/CT检查并经组织病理学检查证实或临床综合诊断确诊的12例SRL患者的临床和影像学资料,其中男性7例、女性5例,年龄(50±15)岁,设为SRL组。同时选取18F-FDG PET/CT显像阳性、最终诊断为RID的患者10例,其中IgG4相关性肾病2例、肾抗中性粒细胞胞浆抗体相关性血管炎8例;男性5例、女性5例,年龄(60±10)岁,设为RID组。选取18F-FDG PET/CT显像肾脏正常的健康受检者10例,其中男性5名、女性5名,年龄(55±10)岁,设为正常对照组。观察和记录肾脏以及肾外组织受累的18F-FDG PET/CT影像学表现,测量并计算肾脏病变或肾皮质最大标准化摄取值(SUVmax)、肾脏病变或肾皮质SUVmax与肝脏平均标准化摄取值(SUVmean)的比值(SUV ratio)及肾外受累组织SUVmax。3组受检者SUVmax、SUVratio的比较采用单因素方差分析,SRL组与RID组肾外受累病变18F-FDG摄取SUVmax的比较采用独立样本t检验。 结果 12例SRL患者中,受累肾脏18F-FDG PET/CT显像表现为双侧肾脏多发结节与肿物型6例,肾脏弥漫性肿胀型6例,病变摄取18F-FDG均异常增高。10例RID患者中,受累肾脏18F-FDG PET/CT显像均表现为双肾弥漫性肿胀型,肾实质弥漫性18F-FDG摄取增高,与肾脏弥漫性肿胀型SRL表现相似。在肾外受累病变方面,RID组多有常见好发的累及部位,SRL组多伴全身不同组织脏器的受累,分布无规律性。SRL组患者肾脏病变的SUVmax、SUVratio显著高于RID组(21.88±12.04对9.09±3.51、11.38±6.52对3.67±1.12),2组肾脏病变的SUVmax、SUVratio亦均显著高于正常对照组(SUVmax=3.23±0.39、SUV ratio=1.47±0.25),且差异均有统计学意义(F=17.189、18.361,均P<0.001)。SRL组肾外受累病变的SUVmax明显高于RID组(27.67±15.09对7.55±3.70),且差异有统计学意义(t=−3.889,P=0.001)。 结论 18F-FDG PET/CT对SRL的诊断和全身受累范围的评估有较好的临床应用价值,且有助于与RID的鉴别。 -
关键词:
- 肾脏 /
- 淋巴瘤 /
- 正电子发射断层显像术 /
- 体层摄影术,X线计算机 /
- 氟脱氧葡萄糖F18 /
- 免疫球蛋白G4相关疾病 /
- 抗中性粒细胞胞浆抗体相关性血管炎
Abstract:Objective To evaluate the diagnostic value of 18F-fluorodeoxyglucose (FDG) PET/CT imaging in patients with secondary renal lymphoma (SRL) and its differential analysis with renal immune disease (RID). Methods The 18F-FDG PET/CT images and clinical characteristics of 12 patients with SRL confirmed by histopathological examination or clinical comprehensive diagnosis in Tianjin First Central Hospital from December 2017 to December 2020 were analyzed retrospectively. The patients in the SRL group comprised 7 males and 5 females, aged 50±15 years. At the same time, 10 patients with positive 18F-FDG PET/CT imaging and final diagnosis of RID were selected, including 2 cases of IgG4-related kidney disease and 8 cases of antineutrophil cytoplasmic antibody-associated vasculitis. These 5 males and 5 females, aged 60±10 years, comprised the RID group. Ten healthy subjects with normal kidneys by 18F-FDG PET/CT imaging were selected as the healthy control group (5 males and 5 females, aged 55±10 years). The 18F-FDG PET/CT features of renal and extrarenal invasion were observed and recorded. The maximal standardized uptake value (SUVmax) of renal lesion or renal cortex, the ratio of SUVmax in renal lesion or renal cortex to mean standardized uptake value (SUVmean) of liver, and SUVmax of extrarenal invasions were measured and calculated. One-way ANOVA was used to compare SUVmax and ratio of standardized uptake value (SUVratio) among the three groups, and independent sample t test was used to compare SUVmax of extrarenal 18F-FDG uptake in the SRL group and RID group. Results The 12 patients with SRL exhibited multifocal masses (n=6) and diffuse nephromegaly (n=6) in bilater kidneys with abnormally increased 18F-FDG uptake. In 10 patients with RID, the 18F-FDG PET/CT imaging of the affected kidneys showed bilateral diffuse nephromegaly with increased 18F-FDG uptake of renal parenchyma, which was similar to diffuse nephromegaly in SRL. However, in terms of extrarenal involvement, the patients in the RID group had common sites of involvement, and the patients in the SRL group were mostly associated with the involvement of different tissues and organs of the whole body, with irregular distribution. Statistical analysis showed that SUVmax and SUVratio of renal lesions in the SRL group were significantly higher than those in the RID group (21.88±12.04 vs. 9.09±3.51 and 11.38±6.52 vs. 3.67±1.12, respectively), and SUVmax and SUVratio of renal lesions in the two groups were significantly higher than those in the healthy control group (SUVmax=3.23±0.39, SUVratio=1.47±0.25; F=17.189, 18.361; both P<0.001). 18F-FDG SUVmax of extrarenal lesions in the SRL group was significantly higher than that in the RID group (27.67±15.09 vs. 7.55±3.70, t=−3.889, P=0.001). Conclusion 18F-FDG PET/CT has a good clinical value in the diagnosis of SRL and the evaluation of systemic involvement, and it is helpful in distinguishing SRL from RID. -
图 5 健康受检者(男性,60岁)的18F-FDG PET/CT显像图A为全身最大密度投影图,显示双侧肾盂、输尿管及膀胱内可见生理性18F-FDG分布,其余体部未见明显异常摄取;B为横断面PET/CT融合图,显示18F-FDG主要分布于双侧肾盏肾盂内,双肾实质仅可见少量、均匀的放射性分布,SUVmax=3.38,SUVratio=1.50;C为横断面CT图,显示双肾形态、结构及密度未见明显异常。FDG为氟脱氧葡萄糖;PET为正电子发射断层显像术;CT为计算机体层摄影术;SUVmax为最大标准化摄取值;SUVratio为正常肾皮质SUVmax/肝脏平均标准化摄取值的比值
Figure 5. 18F-FDG PET/CT image of healthy subject (male, 60 years old)
表 1 3组受检者的临床资料
Table 1. Clinical data of subjects in three groups
组别 年龄( ±s,岁)$\bar x$ 男/女
(例)血肌酐水平[M(Q1, Q3),μmol/L] 发热
[例(%)]腰部不适
[例(%)]血尿
[例(%)]蛋白尿
[例(%)]继发性肾淋巴瘤组
(n=12)50±15 7/5 80(50,105) 1(8) 6(50) 1(8) 6(50) 肾脏免疫性疾病组
(n=10)60±10 5/5 89(71,121) 7(70) 4(40) 5(50) 5(50) 正常对照组(n=10) 55±10 5/5 67(60,79) 0(0) 0(0) 0(0) 0(0) 注:血肌酐水平正常参考值为45~84 μmol/L -
[1] Ganeshan D, Iyer R, Devine C, et al. Imaging of primary and secondary renal lymphoma[J]. AJR Am J Roentgenol, 2013, 201(5): W712−W719. DOI: 10.2214/AJR.13.10669. [2] Arimoto MK, Nakamoto Y, Higashi T, et al. Intra- and inter-observer agreement in the visual interpretation of interim 18F-FDG PET/CT in malignant lymphoma: influence of clinical information[J]. Acta Radiol, 2018, 59(10): 1218−1224. DOI: 10.1177/0284185117751279. [3] Glaudemans AWJM, de Vries EF, Galli F, et al. The use of 18F-FDG-PET/CT for diagnosis and treatment monitoring of inflammatory and infectious diseases[J]. Clin Dev Immunol, 2013, 2013: 623036. DOI: 10.1155/2013/623036. [4] Lindenberg L, Mena E, Choyke PL, et al. PET imaging in renal cancer[J]. Curr Opin Oncol, 2019, 31(3): 216−221. DOI: 10.1097/CCO.0000000000000518. [5] Bahure S, Cheung JCY, Lin M. Utility of FDG-PET in primary renal lymphoma[J]. Clin Exp Nephrol, 2015, 19(1): 158−159. DOI: 10.1007/s10157-014-1014-x. [6] Corlu L, Rioux-Leclercq N, Ganard M, et al. Renal dysfunction in patients with direct infiltration by B-cell lymphoma[J/OL]. Kidney Int Rep, 2019, 4(5): 688−697[2021-03-21]. https://www.kireports.org/article/S2468-0249(19)30052-X/fulltext. DOI: 10.1016/j.ekir.2019.02.008. [7] Quattrocchio G, Roccatello D. IgG4-related nephropathy[J]. J Nephrol, 2016, 29(4): 487−493. DOI: 10.1007/s40620-016-0279-4. [8] Wang MN, Xu H, Xiao L, et al. Prognostic value of functional parameters of 18F-FDG-PET images in patients with primary renal/adrenal lymphoma[J]. Contrast Media Mol Imaging, 2019, 2019: 2641627. DOI: 10.1155/2019/2641627. [9] Mitsuyama T, Nishio A, Takaoka M, et al. A case of IgG4-related disease associated with diffuse large B cell lymphoma[J]. Clin J Gastroenterol, 2013, 6(1): 63−68. DOI: 10.1007/s12328-012-0345-y. [10] Schirmer JH, Hoyer BF. IgG4-related disease[J]. Dtsch Med Wochenschr, 2019, 144(24): 1726−1730. DOI: 10.1055/a-0857-1007. [11] 吴哲, 唐怡, 江国露, 等. IgG4相关肾病的CT影像特征[J]. 中国医学科学院学报, 2020, 42(6): 711−716. DOI: 10.3881/j.issn.1000-503X.12587.
Wu Z, Tang Y, Jiang GL, et al. Computed tomography imaging features of IgG4-related nephropathy[J]. Acta Acad Med Sin, 2020, 42(6): 711−716. DOI: 10.3881/j.issn.1000-503X.12587.[12] Yates M, Watts R. ANCA-associated vasculitis[J]. Clin Med (Lond), 2017, 17(1): 60−64. DOI: 10.7861/clinmedicine.17-1-60. [13] 张清, 周惠琼, 李艳红, 等. 抗中性粒细胞胞质抗体相关性血管炎46例临床分析[J]. 中华医学杂志, 2016, 96(27): 2146−2149. DOI: 10.3760/cma.j.issn.0376-2491.2016.27.007.
Zhang Q, Zhou HQ, Li YH, et al. The clinical analysis of 46 cases with antineutrophil cytoplasmic antibody-associated vasculitis[J]. Natl Med J China, 2016, 96(27): 2146−2149. DOI: 10.3760/cma.j.issn.0376-2491.2016.27.007.[14] He YL, Du XC, Ding N, et al. Spectrum of IgG4-related disease on multi-detector CT: a 5-year study of a single medical center data[J]. Abdom Imaging, 2015, 40(8): 3104−3116. DOI: 10.1007/s00261-015-0527-4. [15] 潘博, 展凤麟, 倪明, 等. 18F-FDG PET/CT显像在肾脏转移瘤中的诊断价值[J]. 中国临床医学影像杂志, 2020, 31(5): 343−345, 349. DOI: 10.12117/jccmi.2020.05.009.
Pan B, Zhan FL, Ni M, et al. The diagnostic value of 18F-FDG PET/CT for renal metastases[J]. J China Clin Med Imaging, 2020, 31(5): 343−345, 349. DOI: 10.12117/jccmi.2020.05.009.[16] Nicolau C, Sala E, Kumar A, et al. Renal masses detected on FDG PET/CT in patients with lymphoma: imaging features differentiating primary renal cell carcinomas from renal lymphomatous involvement[J]. AJR Am J Roentgenol, 2017, 208(4): 849−853. DOI: 10.2214/AJR.16.17133. [17] Zabrocka E, Sierko E, Jelski S, et al. Simultaneous occurrence of non-Hodgkin lymphoma, renal cell carcinoma and oncocytoma: a case report[J]. Mol Clin Oncol, 2016, 5(4): 455−457. DOI: 10.3892/mco.2016.970. [18] Zhao YY, Wu CX, Li W, et al. 2-[18F]FDG PET/CT parameters associated with WHO/ISUP grade in clear cell renal cell carcinoma[J]. Eur J Nucl Med Mol Imaging, 2021, 48(2): 570−579. DOI: 10.1007/s00259-020-04996-4.