基于MRI弥散成像的直方图纹理分析鉴别肝脏局灶性结节性增生和少脂型肝血管平滑肌脂肪瘤

肝局灶性结节性增生(focal nodular hyperplasia, FNH)是一种较少见的良性富血供肿瘤样病变，是肝细胞对局部血管异常产生的一种反应性增生，而非真正意义上的肿瘤[1]。肝脏血管平滑肌脂肪瘤是肝脏内少见的肿瘤，由增生的厚壁血管、平滑肌及成熟的脂肪组织构成，且3种成分构成比例、分布各不相同，且具有潜在的恶性转化和自发破裂的危险，应该积极手术治疗[2]。肝脏血管平滑肌脂肪瘤可分为4 种类型：脂瘤型（脂肪含量≥ 70%）、肌样型（脂肪含量≤ 10%，上皮样型及梭形细胞型）、血管型（以多发粗大、扭曲的畸形血管为主）及混合型（3 种组成成分比例相近）[3]。肌样型及血管型是含微量成熟脂肪的少脂型血管平滑肌脂肪瘤（Low-fat hepatic angiomyolipoma,LF-HAML)，与肝癌、肝腺瘤及FNH等肝脏富血供病变鉴别困难，术前FNH和LF-HAML在临床和影像表现存在较多的重叠[4]，目前国内外对此研究较少，因此准确诊断并鉴别对确定治疗方案和改善患者预后至关重要, 纹理分析是影像组学研究的基础，在肿瘤病灶提取、定性、疗效评估及预后预测方面具有较高的价值[5-6]。笔者旨在探讨基于直方图的MRI-DWI纹理特征方法鉴别两种病变的价值。     

Benign mesenchymal tumours and tumour‐like lesions in end‐stage renal disease

Aims: Mesenchymal neoplasms of the kidney are rare, and most represent sporadic angiomyolipomas. A few haemangiomas have been reported in end‐stage renal disease (ESRD) but, to date, no study has focused on the frequency and morphological spectrum of mesenchymal lesions in ESRD. Methods and results: We evaluated retrospectively 90 nephrectomy specimens with ESRD. Haemangiomas were detected in eight cases (8.8%; six males and two females; mean age: 55 years); four were multifocal and four had concurrent renal epithelial neoplasms. Lesions involved the medulla (three), cortex (two) or both (three), and the size range was 1–25 mm (mean 4.8 mm). Histologically, all were capillary haemangiomas with an at least focally detectable spleen‐like anastomosing pattern. All tumours stained positively for CD31 and FLI‐1, but none expressed pankeratin (KL‐1), podoplanin/D2‐40, HHV8 or GLUT‐1. Minute angiomyolipomas (mean size 2.3 mm) were detected in four patients (mean age 49.5 years). Tumour‐like smooth muscle proliferations were seen surrounding muscular arteries (eight), occasionally admixed with fat extending from the renal sinus mimicking angiomyolipoma. No similar tumours were found in 105 control kidneys. Conclusions: Benign haemangiomas are not uncommon in ESRD, but may be under‐recognized. They display distinctive morphology and should be distinguished from angiosarcomas and capillary‐rich renal cell carcinomas.     

Tuberous sclerosis complex: Recent advances in manifestations and therapy

Tuberous sclerosis complex is an autosomal dominant inherited disorder characterized by generalized involvement and variable manifestations with a birth incidence of 1:6000. In a quarter of a century, significant progress in tuberous sclerosis complex has been made. Two responsible genes, TSC1 and TSC2, which encode hamartin and tuberin, respectively, were discovered in the 1990s, and their functions were elucidated in the 2000s. Hamartin–Tuberin complex is involved in the phosphoinositide 3‐kinase–protein kinase B–mammalian target of rapamycin signal transduction pathway, and suppresses mammalian target of rapamycin complex 1 activity, which is a center for various functions. Constitutive activation of mammalian target of rapamycin complex 1 causes variable manifestations in tuberous sclerosis complex. Recently, genetic tests were launched to diagnose tuberous sclerosis complex, and mammalian target of rapamycin complex 1 inhibitors are being used to treat tuberous sclerosis complex patients. As a result of these advances, new diagnostic criteria have been established and an indispensable new treatment method; that is, “a cross‐sectional medical examination system,” a system to involve many experts for tuberous sclerosis complex diagnosis and treatments, was also created. Simultaneously, the frequency of genetic tests and advances in diagnostic technology have resulted in new views on symptoms. The numbers of tuberous sclerosis complex patients without neural symptoms are increasing, and for these patients, renal manifestations and pulmonary lymphangioleiomyomatosis have become important manifestations. New concepts of tuberous sclerosis complex‐associated neuropsychiatric disorders or perivascular epithelioid cell tumors are being created. The present review contains a summary of recent advances, significant manifestations and therapy in tuberous sclerosis complex.     

Fibrosarcoma Mimicking Plasmacytoma or Carcinoma: An Ultrastructural Study of 4 Cases

Because the fibroblast has a remarkable capability of phenotypic modulations, reflected in both morphologic and immunohistochemical (IHC) changes, ultrastructural studiesare mandatory to identify the variants of fibroblasts. Myofibroblasts or histiofibroblasts are such examples, demonstrating chimeric ultrastructural features of fibroblastic cells in common with smooth muscle cells or with histiocytes, respectively. The presence of epithelioid fibroblastic cells sharing morphologic features with epithelial or plasma cells has not been yet characterized. The authors identified 4 cases of fibrosarcomas (FS) characterized by an unusual phenotype and associated with peculiar ultrastructural findings. The electron microscopic (EM) findings were correlated with the histologic appearance and immunoprofile. All tumors were located in the extremities, 3 in soft tissues and 1 in the bone. By light microscopy 2 cases were composed predominantly by round uniform cells with a striking plasmacytoid appearance. One case mimicked carcinoma, composed predominantly by epithelioid cells and scattered giant tumor cells. The fourth case showed a mixture of plasmacytoid-like and epithelioid cells. By IHC, tumor cells were positive for vimentin and in 2 cases also for epithelial membrane antigen. Kappa/lambda light chain and cytokeratins markers were negative. By EM all 4 tumors showed in addition to classic features of fibroblasts, unusual epithelial-type features, such as secretory granules of "neurosecretory-type" (3 cases), rudimentary cell junctions (3 cases), microvilli (2 cases), and lumen-like structures (1 case). One plasmacytoid-type tumor showed finely granular extracellular deposits. The study describe 4 examples of fibrosarcomas with unusual features at the ultrastructural level, which are associated microscopically with a peculiar phenotype, mimicking plasmacytoma or carcinoma. These findings broaden the spectrum of fibroblastic cell variants in neoplasia.     

Immunohistochemical validation of INI1/SMARCB1 in a spectrum of musculoskeletal tumors: An experience at a Tertiary Cancer Referral Centre

The purpose of this study was to evaluate and validate immunohistochemical (IHC) expression of INI1/SMARCB1 in various musculoskeletal tumors in the light of the established literature.     

Multifocal and microscopic chromophobe renal cell carcinomatous lesions associated with ‘capsulomas’ without FCLN gene abnormality

Chromophobe renal cell carcinoma (RCC) accounts for approximately 5% of renal epithelial neoplasms. Multiple and/or bilateral chromophobe RCCs in an individual are generally rare but frequently occur in patients with Birt–Hogg–Dubé syndrome (BHDS) and in patients with tuberous sclerosis complex (TSC). The responsible genes in both BHDS and TSC act as tumor suppressors. Therefore, it seems that some genetic backgrounds are required for the generation and progression of multiple chromophobe RCCs. Here, we report a case of multiple and bilateral chromophobe RCCs along with several small‐sized capsular angiomyolipomas known as ‘capsulomas’ in a 39‐year‐old woman who had neither a particular medical history nor specific gene mutation. There has been no report of sporadic multiple chromophobe RCCs and ‘capsulomas’ developing in a patient without genetic features, having potential for novel genetic variation.     

上皮样炎性肌纤维母细胞肉瘤1例临床病理观察

目的分析上皮样炎性肌纤维母细胞肉瘤(EIMS)的临床及病理特征,旨在提高对本病的认识及鉴别。方法对1例EIMS进行免疫组化染色,荧光原位杂交检测ALK基因重排,观察其病理特点并复习文献。结果患者女,56岁,腹痛2月余。肿物位于肠系膜,直径约15 cm,切面黏液样外观。镜下见肿瘤富于黏液背景,瘤细胞呈弥漫或团块状分布,细胞呈上皮样,圆形、多边形、短梭形,胞质丰富、核偏位,核分裂活跃,间质内见显著炎细胞浸润。免疫组化显示,ALK(5A4)及ALK(1A4)阳性均特征性定位于肿瘤细胞核膜。FISH检测显示ALK基因重排阳性。此外,该例肿瘤还表达vimentin、Desmin、D2-40、WT-1、CD99。术后约2个月后复发,生存期约5个月。结论EIMS是罕见的一种软组织恶性肿瘤,恶性度极高,临床表现无特异性,诊断主要依赖病理形态学及免疫组化染色。     

Hepatic Angiomyolipomas: Ultrasonic Characteristics of 25 Patients from a Single Center

Twenty-five pathologically proven hepatic angiomyolipomas (AMLs) were included in the study. Ultrasonic features of hepatic AMLs were reviewed. Three types of echogenicity were observed on ultrasound examination: (i) strong hyper-echogenicity, (ii) moderate hyper-echogenicity and (iii) hypo-echogenicity. Vascular signals within tumors could be detected in 22 (88.00%) tumors as multiple punctiform, filiform or dendriform signals by color Doppler flow imaging. Based on the enhancement patterns in the arterial, portal and late phases, the features of hepatic AMLs on contrast-enhanced ultrasound were divided into four subtypes: (i) “fast in slow out” (68.00%, n = 17); (ii) “fast in same out” (16%, n = 4); (iii) “fast in fast out” (12.00%, n = 3); and (iv) “fast in uneven out” (4.00%, n = 1). Contrast-enhanced ultrasound diagnosed 22 (88.00%) tumors as benign tumors and 13 (52.00%) as hepatic AMLs. Four cases were misdiagnosed as hepatic hemangioma, five cases as focal nodular hyperplasia (total = 36.00%). The rate of correct diagnosis of hepatic AMLs increased significantly from 24.00% for ultrasound alone to 52.00% for contrast-enhanced ultrasound. Therefore, information obtained from ultrasound, color Doppler flow imaging and contrast-enhanced ultrasound should be combined to improve diagnosis.