Angiosarcoma of the kidney with minute clear cell carcinomas: A case report

A case of renal angiosarcoma with minute clear cell carcinomas in a 61-year-old male is described. The tumor was clinically considered a renal cell carcinoma. The lesion, removed by nephrectomy, was an unencapsulated hemorrhagic mass measuring 8.0 cm in diameter. The tumor was histologically characterized by anastomosing vascular channels lined by cytologically atypical endothelial cells. The tumor cells reacted positively with CD31, factor-VIII related antigen, and CD34. A few minute clear cell carcinomas measuring less than 1 mm were observed in the periphery of the angiosarcoma. There was no transition between angiosarcoma and renal cell carcinoma. The patient died of a widespread disease 13 months after surgery. This tumor is considered a primary renal angiosarcoma with clear cell carcinomas and not a sarcomatoid carcinoma.     

The evolution of collagen expression in sarcomatoid renal cell carcinoma

The development of a sarcomatoid morphotype is recognized as an extreme form of dedifferentiation in renal cell carcinoma and is associated with a poor prognosis. Although sarcomatoid renal cell carcinoma shows pronounced spindle cell morphology, clear cell renal cell carcinoma may show early spindle cell change with cellular elongation, and the prognostic significance of this is debated. To determine the relationship between sarcomatoid renal cell carcinoma and clear cell renal cell carcinoma showing early spindle cell change, we have investigated collagen expression using immunohistochemistry in these 2 tumor types. Both sarcomatoid renal cell carcinoma and early spindle cell change tumors showed pericellular interstitial expression of collagen types I and III, whereas sarcomatoid renal cell carcinoma also showed cytoplasmic expression of these collagen types. Expression of these collagen types in typical clear cell renal cell carcinoma was, in occasional cases, limited to faint and patchy staining in a pericellular interstitial distribution. Tumor cells did not stain for collagen type IV in sarcomatoid renal cell carcinoma, early spindle cell change, or typical clear cell renal cell carcinoma. In sarcomatoid renal cell carcinoma, there was diffuse pericellular expression of collagen type V and patchy pericellular expression of collagen type VI, whereas early spindle cell change tumors showed patchy pericellular staining with antibodies to collagen type V. Collagen type VI expression in early spindle cell change was largely confined to the vascular adventitia and areas of scarring, although very occasional foci of faint interstitial staining were also seen. In typical clear cell renal cell carcinoma, staining of collagen types V and VI was limited to the vascular adventitia and foci of desmoplasia, whereas no staining of tumor cell cytoplasm were seen. This study has shown that collagen expression of sarcomatoid renal cell carcinoma differs from that of early spindle cell change and provides validating evidence that these 2 morphotypes should not be considered together for classification purposes.     

Metastatic renal cell carcinoma presenting as a gallbladder polyp

Clear cell renal cell carcinoma accounts for approximately 3% of all adult malignancies and 85% of all primary renal malignancies. Clear cell renal cell carcinoma (ccRCC) metastasis to the gallbladder is extremely rare and often presents as a metachronous metastasis following several years of tumour free disease. We report a case of a 78-year-old female with metastatic ccRCC to the gallbladder. During follow-up ultrasound imaging, a polypoid gallbladder mass was discovered incidentally. The previous medical history is significant for total nephrectomy for left-sided ccRCC 6 years ago. A new suspicious intraluminal polypoid gallbladder mass in a patient with a history significant for clear cell renal cell carcinoma should alert the physician to consider metastatic clear cell renal cell carcinoma.     

Simultaneous double primary clear cell carcinomas of liver and kidney: a case report and review of literature

Reported herein are simultaneous double primary clear cell carcinomas arising from liver and kidney. A 63-year-old man underwent a partial wedge nephrectomy of the right kidney in a surgical resection for hepatocellular carcinoma. Coincidently, on histology the tumors in liver and kidney were consisted of clear cancer cells, which arranged in haphazardly intermixed pattern without capsules. Immunohistochemically, the clear neoplastic cells in the liver were positive for HepPar-1, GPC3, and negative for nephrogenic markers; however, renal clear neoplastic cells were positive for CD10, RCC and Pax-8, but negative to liver-derived markers. These findings led to the diagnosis of simultaneous double primary clear cell carcinomas of kidney and liver. Multiple primary carcinomas of kidney and liver, especially both are primary clear cell carcinomas, are extremely rare neoplasms, only 1 case has been reported previously until now. To our knowledge, this is a report of multiple primary carcinomas arising from the liver and kidney and reminders us of differentiation diagnosis with carcinoma metastasis.     

Sarcomatoid conversion of clear cell renal cell carcinoma in relation to epithelial-to-mesenchymal transition

Approximately 8% of clear cell renal cell carcinoma cases contain regions of radically different morphology, demonstrating a mesenchymal appearance histologically resembling sarcomas. These biphasic neoplasms are called sarcomatoid clear cell renal cell carcinoma. Patients diagnosed with sarcomatoid clear cell renal cell carcinoma face a considerably worse prognosis due to an increased propensity for metastasis. In the present study we investigate whether the sarcomatoid conversion of clear cell renal cell carcinoma could be interpreted as linked to the process of epithelial-mesenchymal transition. Using 6 biphasic clear cell renal cell carcinoma cases we show that sarcomatoid clear cell renal cell carcinoma shares characteristic markers associated with loss of von Hippel-Lindau tumor suppressor with conventional clear cell renal cell carcinoma and also exhibits a markedly higher proliferative index. Furthermore the sarcomatoid elements demonstrate an enhanced expression of epithelial-mesenchymal transition related mesenchymal markers as compared with the clear cell renal cell carcinoma counterparts. We further selected a representative case, clinically demonstrating direct overgrowth of the sarcomatoid component into the liver and colon, for extended immunohistochemical characterization, resulting in a further set of positive and negative epithelial-mesenchymal transition markers as well as pronounced transforming growth factor β positivity, indicating that sarcomatoid clear cell renal cell carcinoma may be associated to epithelial-mesenchymal transition. Transforming growth factor β1 exposure of in vitro cultured primary clear cell renal cell carcinoma cells resulted in cells adopting a mesenchymal morphology similar to sarcomatoid clear cell renal cell carcinoma. Corresponding changes in RNA levels for key epithelial-mesenchymal transition markers were also seen. We therefore suggest that sarcomatoid clear cell renal cell carcinoma morphologically and immunohistochemically may represent a completed epithelial-mesenchymal transition and that transforming growth factor β1 could be an important driving force during the sarcomatoid transdifferentiation of clear cell renal cell carcinoma.     

Histological, genomic and clinical heterogeneity of clear cell hepatocellular carcinoma

AIMS: The aim of the study was to determine whether clear cell type hepatocellular carcinoma should still be regarded as a separate uniform diagnostic entity. METHODS AND RESULTS: We retrospectively studied 118 cirrhotic patients with hepatocellular carcinoma treated by orthotopic liver transplantation, and 31 noncirrhotic patients with hepatocellular carcinoma treated by either liver surgical resection or transplantation. The pathology of all liver resections was reviewed. Microsatellite instability was performed on paraffin-embedded samples at loci located on chromosomes 2p, 3p, 5q, 8q, 9p, 13q, 16q and 17p. Among the 118 cirrhotic patients, 10 (8.5%) had a clear cell hepatocellular carcinoma; these had clinical characteristics and prognosis similar to the other cirrhotic patients. No genetic alterations were detected in these tumours. Among the 31 noncirrhotic patients, one (3.2%) had a clear cell hepatocellular tumour. This 170-mm tumour had a lipid density on computed tomography, and its histology resembled chromophobe cell renal carcinoma. Furthermore, this tumour had unusual genomic alterations, with microsatellite instability in 6/8 chromosome loci. CONCLUSIONS: Clear cell hepatocellular carcinoma is a heterogeneous entity in which a chromophobe cell subtype should be identified.     

VHL mutations and their correlation with tumour cell proliferation, microvessel density, and patient prognosis in clear cell renal cell carcinoma.

Mutations of the von Hippel-Lindau (VHL) gene are considered critical for the initiation of clear cell renal cell carcinoma. The VHL protein is involved in regulation of the cell cycle and neo-vascularization. In this study, the association of VHL mutations with tumour cell proliferation, angiogenesis, and clinical outcome was analysed in 113 clear cell renal cell carcinomas. The degree of angiogenesis and tumour cell proliferation was immunohistochemically determined by counting microvessels (microvessel density, anti-CD34 antibody) and cells with proliferating activity (Ki-67 labelling index, MIB-1 antibody). Forty-eight different VHL sequence alterations were found in 38 of 113 patients (34%) by direct sequencing. Nineteen VHL mutations were frameshifts and nonsense mutations, predicted to change the open reading frame of VHL. These 'loss-of-function' mutations correlated with worse prognosis in univariate analysis (p=0.02). Tumour grade, stage, microvessel density, and tumour cell proliferation were not associated with VHL alterations. These findings may indicate that 'loss-of-function' VHL mutations are involved in the progression of a clear cell renal cell carcinoma subset, whereas regulation of angiogenesis and proliferation of renal carcinoma in vivo is apparently not directly influenced by VHL alterations.     

Metastasis of renal cell carcinoma to central nervous system hemangioblastoma in two patients with von Hippel-Lindau disease

Here we report tumor-to-tumor metastases identified in two patients with von Hippel-Lindau (VHL) disease. The first patient had bilateral renal carcinomas and multiple cerebellar hemangioblastomas, and the second patient had a renal carcinoma and multiple hemangioblastomas in the retina, cerebellum and spinal cord. A cerebellar lesion from the first patient and a spinal lesion from the second patient contained two distinct components. The inner part of these tumors consisted of a nested mass of polygonal clear cells that expressed cytokeratin and epithelial membrane antigen, while the outer part of the tumors showed proliferation of capillaries and intervening foamy stromal cells that were negative for cytokeratin and epithelial membrane antigen. The tumors were thus considered to be hemangioblastomas complicated by metastatic lesions of renal cell carcinoma of clear cell type. These cases indicate that tumor-to-tumor metastasis should be considered when hemangioblastoma contains a clear cell carcinoma component in the setting of VHL disease, and that immunohistochemical staining for cytokeratin and epithelial membrane antigen is useful for the diagnosis.     

Subtypes of renal cell carcinoma with defined genomic alterations: diagnostic and prognostic significance

The World Health Organization (WHO) 2016 classification of renal neoplasia defines renal cell carcinomas (RCCs) with genomic alterations: (1) succinate dehydrogenase deficient (SDH) RCC, (2) hereditary leiomyomatosis and renal cell carcinoma (HLRCC) syndrome-associated RCC and (3) the MiT family translocation carcinoma (Xp11 translocation carcinoma and t(6;11) carcinoma). Genomic alterations also define two syndromes associated with RCC that have a varied histology; tuberous sclerosis complex and Birt-Hogg-Dube. This review will examine the WHO entities and the two aforementioned syndromes, and discuss a genomic alteration (TCEB1 mutation) that appears to define a subset of clear cell RCCs that histomorphologically overlap with clear cell tubulopapillary RCC. The focus will be on diagnostic considerations from the pathologic perspective, and include discussion of clinical features, prevalence, prognosis, common and uncommon immunohistochemistical stains and molecular testing.     

Renal cell carcinoma with rhabdoid features: an aggressive neoplasm

AIMS: Only a few reports on renal cell carcinoma with rhabdoid features have been published. This study was performed to investigate the clinicopathological characteristics of renal cell carcinomas with rhabdoid features. METHODS AND RESULTS: Among 253 cases of renal cell carcinoma in adults, eight cases with rhabdoid features were detected. Rhabdoid areas ranged from 10% to 90% of each of the cases. Seven of the eight cases were TNM stage III or IV, and four of the eight cases died within 8 months of surgery. Immunohistochemically, the rhabdoid areas were positive for CAM 5.2 (4/8), AE1/AE3 (6/8), epithelial membrane antigen (6/8) and vimentin (8/8), and negative for myogenetic markers (0/8). The mean MIB-1 labelling index in the rhabdoid areas was higher than that in the definite carcinomatous areas. Ultrastructurally, perinuclear whorls of intermediate filaments were demonstrated in three of the eight cases using paraffin-embedded blocks. CONCLUSIONS: The rhabdoid areas in renal cell carcinoma have histological, immunohistochemical and ultrastructural similarities to malignant rhabdoid tumours. Renal cell carcinoma with rhabdoid features is a highly aggressive neoplasm and its malignant behaviour may be due to the high cell-proliferative activity of the rhabdoid areas. Rhabdoid features in renal cell carcinoma may represent the endpoint of clonal evolution of renal cell carcinoma (especially in clear cell type cases).     

A synchronous hepatocellular carcinoma and renal cell carcinoma treated with radio-frequency ablation

Radio-frequency ablation (RFA) is a curative treatment for hepatocellular carcinoma (HCC). Percutaneous RFA has been shown to be beneficial for patients with small renal cell carcinoma (RCC) lacking indications for resection. We experienced the case of a 53-year-old male who had conditions that suggested HCC, RCC, and alcoholic liver cirrhosis. Abdominal contrast-enhanced computed tomography (CT) and magnetic resonance image showed liver cirrhosis with 2.8 cm ill-defined mass in segment 2 of the liver and 1.9 cm hypervascular mass in the left kidney. These findings were compatible with the double primary cancers of HCC and RCC. Transarterial chemoembolization (TACE) was performed to treat the HCC. After the TACE, a focal lipiodol uptake defect was noticed on a follow up CT images and loco-regional treatment was recommended. Therefore, we performed RFAs to treat HCC and RCC. There was no evidence of recurrence in the follow up image after 1 month.     

Expression of EphA2 protein is positively associated with age,tumor size and Fuhrman nuclear grade in clear cell renal cell carcinomas

The receptor tyrosine kinase of EphA2 has been shown frequently overexpressed in various types of human carcinomas, which implicated that it plays important roles in carcinogenesis. Although EphA2 protein expression has been investigated in many types of human carcinomas, the relationship between the expression of EphA2 protein in clear cell renal cell carcinoma was not well documented. In the present study, using specific anit-EphA2 polyclonal antibody and immunohistochemistry, we evaluated EphA2 protein expression levels in clear cell RCC specimens surgically resected from 90 patients. Our results shows that EphA2 protein was positively expressed in all normal renal tubes of 90 samples (100%, 3+), which was expressed at low levels in renal cortex but high levels in the collecting ducts of the renal medulla and papilla. EphA2 was negatively or weakly expressed in 30 out of 90 samples (33.3%, 0/1+), moderately expressed in 24 samples (26.7%, 2+) and strongly expressed in 36 samples (40%, 3+). Expression of EphA2 was positively associated with age (P=0.029), tumor diameters (P<0.001) and Fuhrman nuclear grade (P<0.001). Our results indicate that EphA2 variably expressed in clear cell renal cell carcinomas. High expression of EphA2 was more often found in big size and high nuclear grade tumors, which indicated EphA2 protein may be used as a new marker for the prognosis of clear cell renal cell carcinoma.     

多囊性肾透明细胞癌的病理学诊断

目的：探讨多囊性肾透明细胞癌的临床病理特点。方法：对1例多囊性肾透明细胞癌进行了免疫组化染色,并进行文献复习。结果：本例右肾肿物18年。大体见肿物由多发不等的囊腔组成。镜下囊内壁主要由单层立方或柱状上皮被覆,部分为多层并有乳头形成。瘤细胞胞质透亮,无明显异型性。癌细胞免疫表型cytokeratin、CEA和vimentin呈阳性表达。本例诊断为多囊性肾透明细胞癌。结论：多囊性肾透明细胞癌是一种罕见的肾癌病理类型。临床上主要采用根治切除术。本瘤的生物学行为属于低度恶性肿瘤。     

Clear cell papillary renal cell carcinoma: Incidence,morphological features,immunohistochemical profile,and biologic behavior: A single institution study

This study was undertaken to determine the incidence and the clinicopathologic characteristics of those tumors that qualify as clear cell papillary renal cell carcinoma (CCPRCC) by the current definitions. From January 1, 2003 to April 30, 2013, a total of twenty-eight CCPRCC were identified (28/648, 4.3%). CCPRCC showed variable architectural patterns including cystic, papillary, tubular, and acinar. Irrespective of the architecture, the tumors were composed of cuboidal or columnar cells with clear cytoplasm, small vesicular, round or oval nuclei, and inconspicuous nucleoli. Variably thick bundles of smooth muscle actin-positive soft tissue encircled the whole tumors, forming a continuous pseudocapsule. CCPRCC strongly expressed PAX8, CA-IX, CK7, cytokeratin 34betaE12, and vimentin, and were negative for RCC, P504s/AMACR, and TFE3. On ultrastructural examination, CCPRCC showed short microvilli, cytoplasmic interdigitations, nuclear pseudoinclusions, and stromal myofibroblasts. To the best of our knowledge, this is first comprehensive ultrastructural study of CCPRCC in the literature. The major differential diagnostic considerations are clear cell renal cell carcinoma, multilocular cystic renal cell carcinoma, papillary renal cell carcinoma with clear cell changes, and Xp11.2 translocation renal cell carcinoma. CCPRCC seems to have a favorable prognosis. In the current series, none of the patients had local recurrence or metastatic disease.     

PTEN expression in renal cell carcinoma and oncocytoma and prognosis

AIMS: Deletion or inactivation of the tumour suppressor gene PTEN (phosphatase and tensin homologue deleted from chromosome 10) contributes to tumorigenesis in a variety of human carcinomas. The present study evaluated PTEN expression in renal cell carcinomas and oncocytomas. METHODS: A tissue microarray from 493 specimens including renal cell carcinomas (n = 440), oncocytomas (n = 21) and tumour-negative renal tissue (n = 32) from patients (n = 461) was incubated with an anti-PTEN antibody for subsequent analysis of PTEN expression. Furthermore, the effect of PTEN expression on the survival of renal carcinoma patients was evaluated. RESULTS: Renal cell carcinomas, and even more pronouncedly oncocytomas, expressed PTEN predominantly in the cytoplasm. In contrast to oncocytomas, PTEN expression was typically decreased in renal cell carcinoma subtypes. PTEN expression in sarcomatoid renal cell carcinomas was comparable to that in non-sarcomatoid subtypes. The PTEN expression pattern had no significant influence on prognosis. CONCLUSIONS: Renal tumours (renal cell carcinomas and oncocytomas) express PTEN protein predominantly in the cytoplasm. A reduction in PTEN expression appears to be an early step in renal cell carcinogenesis. However, the PTEN expression pattern of renal cell carcinomas apparently is not prognostic for patient survival.     

Spindle and cuboidal renal cell carcinoma,a tumour having frequent association with nephrolithiasis: report of 11 cases including a case with hybrid conventional renal cell carcinoma/ spindle and cuboidal renal cell carcinoma components

AIMS: We present the largest series of an unclassified subtype of renal cell carcinoma, which seems to be a distinct morphological entity and which is sometimes designated as spindle and cuboidal renal cell carcinoma. METHODS AND RESULTS: Eleven cases of spindle and cuboidal renal cell carcinoma were found among 7000 primary renal cell tumours in Pilsen's routine and consultation files. The patients were five men and six women. They ranged in age from 22 to 65 years (mean 56.8). Microscopically, the tumours were composed of two main populations of cells. First, the preponderant type of cells was formed by flattened, spindle cells with sparse cytoplasm. The second cell type was a small cuboidal cell with clear to light eosinophilic cytoplasm. Spindle-shaped cells were arranged in a fascicular pattern often reminiscent of low-grade smooth muscle tumours. Solid areas of spindle cells were also present. Small cuboidal cells formed sparse tubular structures lined by a row of single cells. In addition to all previous published cases of spindle and cuboidal renal cell carcinoma we observed an association of nephrolithiasis in our cases. It was seen in 3/11 of our patients. A previously unreported feature is the occurrence of a conventional renal cell carcinoma component in one of our cases. Seven of our patients are currently well without signs of recurrence or metastasis, one had metastasis in a regional lymph node at the time of nephrectomy, one died of an unrelated condition, and two were lost to follow-up. CONCLUSIONS: We present 11 cases of spindle and cuboidal renal cell carcinoma, which is believed to be a distinctive morphological entity. Our cases were histologically, immunohistochemically and ultrastructurally similar to the previously reported cases of spindle and cuboidal renal cell carcinoma. In contrast to all previously reported cases of spindle and cuboidal renal cell carcinoma, we observed an association with nephrolithiasis in three of our cases; moreover, one of our tumours had a conventional renal cell carcinoma component and another revealed a metastatic focus in a regional lymph node. None of our patients died of the disease. This study confirms that spindle and cuboidal renal cell carcinoma has a low malignant potential.