Renal cell carcinoma with rhabdoid features: an aggressive neoplasm

Nucleolar grade but not Fuhrman grade is applicable to papillary renal cell carcinoma

This study was undertaken to determine the validity of Fuhrman grading in a series of papillary renal cell carcinomas (PRCCs), to examine the interrelationship and prognostic significance of the individual components of the grading system, and further to determine whether any observed predictive value was independent of other prognostic indicators. Ninety cases of PRCC were studied. Fifty-nine tumors were of type 1 and 31 were of type 2. There were 33 TNM stage 1, 26 stage 2, 18 stage 3, and 12 stage 4 tumors, whereas division of cases according to pT category showed 14 pT1a, 20 pT1b, 25 pT2, 15 pT3a, 4 pT3b, and 11 pT4 tumors. Ten tumors were grade 1, 58 grade 2, and 22 grade 3 when predominant Fuhrman grade was assigned, whereas grading according to the high-power field containing the highest grade (focal grade) showed 40 grade 2, 49 grade 3, and 1 grade 4 tumors. Measurements of nuclear size (area, major axis, perimeter) and shape (shape factor, compactness) were undertaken using image analysis. Nuclear area ranged from 27.63 to 116.39 microM, major axis length 6.70 to 14.06 microM, and nuclear perimeter 20.05 to 41.77 microM. Shape factor ranged from 0.805 to 0.878 and compactness from 14.33 to 15.66. Predominant nucleolar grade using the criteria of the Fuhrman classification was nucleolar grade 1 for 13 tumors, nucleolar grade 2 for 56 tumors, and nucleolar grade 3 for 21 tumors. Focal nucleolar grade based on the high-power field showing the greatest degree of nuclear pleomorphism, was grade 2 for 38 tumors and grade 3 for 52 tumors. pT category, TNM stage, focal Fuhrman grade, and PRCC type were significantly associated with survival. Of the various measures of the components of the Fuhrman classification, only focal nucleolar grade was associated with survival, on univariate analysis. On multivariate analysis, focal nucleolar grade and tumor diameter were independently associated with survival, whereas TNM stage retained significance independent of other parameters. It is concluded that assessment of nucleolar prominence rather than Fuhrman grade is applicable for stratification of tumors within TNM stage or pT category for PRCC and that this should be based upon the high-power field showing the greatest degree of nuclear pleomorphism.

Extrarenal rhabdoid tumors of soft tissue: Clinicopathological and molecular genetic review and distinction from other soft-tissue sarcomas with rhabdoid features

Malignant rhabdoid tumor (MRT) of the soft tissue is a rare and highly aggressive tumor that occurs in infancy or childhood. It predominantly involves a deep axial location such as the neck or paraspinal region. Microscopically, the tumor is composed of a diffuse proliferation of rounded or polygonal cells with eccentric nuclei, prominent nucleoli and glassy eosinophilic cytoplasm containing hyaline-like inclusion bodies, arranged in sheets and nests. These characteristic 'rhabdoid cells' are also present in certain soft-tissue sarcomas such as synovial sarcoma, extraskeletal myxoid chondrosarcoma and leiomyosarcoma. The existence of rhabdoid cells in these other sarcomas is correlated with a worse prognosis for the patients. Cytogenetic and molecular analyses have shown abnormalities in the long arm of chromosome 22 and alteration of the hSNF5/INI1 (SMARCB1) gene in renal, extrarenal and intracranial MRT. This gene alteration has been considered to be a specific molecular event in MRT, but a recent study has also demonstrated frequent alteration of this gene in proximal-type epithelioid sarcoma (ES). Both MRT of soft tissue and proximal-type ES show immunoreactivity for vimentin, cytokeratin and epithelial membrane antigen. The tumor cells of proximal-type ES are also occasionally positive for CD34 and beta-catenin, whereas MRT of soft tissue has no immunoreaction for these markers. Detailed clinicopathological and immunohistochemical evaluations are necessary to distinguish MRT of soft tissue from proximal-type ES, because these tumors demonstrated a similar morphology and the same gene alteration.

Eosinophilic cytoplasmic inclusions in papillary renal cell carcinoma

A case of a patient with papillary renal cell carcinoma (RCC) with eosinophilic inclusions is presented. Almost all neoplastic cells contained eosinophilic globules that were stained red by trichrome and were negative for periodic acid-Schiff (PAS) reaction. Immunohistochemically, globules were negative for actin, keratin, vimentin, glially fibrillary acidic protein (GFAP), and neurofilament. Ultrastructurally, globules consisted of electron-dense granular material that is more suggestive of a secretory substance than cytoskeletal filaments. The presence of eosinophilic cytoplasmic inclusions in RCC is rare. In this article, we review similar cases in the literature and discuss the nature of eosinophilic globules.

INI1 expression is retained in composite rhabdoid tumors, including rhabdoid meningiomas

Rhabdoid cells are encountered in specific entities, such as malignant rhabdoid tumor and atypical teratoid/rhabdoid tumor, as well as in composite rhabdoid tumors derived secondarily from other tumor types. Although rhabdoid tumors are uniformly aggressive, distinction of the entity from the phenotype remains important for its therapeutic implications. The majority of malignant rhabdoid tumors and atypical teratoid/rhabdoid tumors affect infants and young children, harbor chromosome 22q deletions, and inactivate the INI1/hSNF5/BAF47 tumor suppressor gene on 22q11.2. In contrast, most composite rhabdoid tumors are diagnosed in adults, with FISH detectable 22q losses the exception rather than the rule. However, this assay remains limited since 22q dosages are maintained in 20-30% of malignant rhabdoid tumors and atypical teratoid/rhabdoid tumors. Furthermore, chromosome 22 losses are common in some parent tumor types, particularly meningiomas. The recently developed INI1 antibody shows loss of nuclear expression in malignant rhabdoid tumors and atypical teratoid/rhabdoid tumors, though its status in composite rhabdoid tumors is largely unknown. Therefore, we utilized immunohistochemistry and FISH to study INI1 expression and 22q dosages, respectively, in 40 composite rhabdoid tumors, including 16 meningiomas, 15 carcinomas, three melanomas, two sarcomas, two glioblastomas, and 1 neuroblastoma. Approximately 70% of rhabdoid meningiomas had a 22q deletion, but this was rare in other tumor types. Except for one retroperitoneal leiomyosarcoma, nuclear INI1 expression was retained in all composite rhabdoid tumors, including meningiomas with 22q deletion. Therefore, we conclude that INI1 immunohistochemistry is a relatively simple, sensitive, and specific technique for distinguishing malignant rhabdoid tumor and atypical teratoid/rhabdoid tumor from composite rhabdoid tumor.

Oncocytic renal neoplasms: diagnostic considerations

Advances in our understanding of renal neoplasia have resulted in recognition of numerous tumors that are composed predominantly of cells with abundant eosinophilic cytoplasm. This article discusses the features of renal oncocytoma (including oncocytosis), chromophobe renal cell carcinoma (RCC), and clear cell RCC; explores the relationship between renal oncocytoma and chromophobe RCC; briefly discusses other tumors with abundant eosinophilic cytoplasm; and emphasizes the differential diagnosis of such tumors.

Clear cell renal cell carcinoma with syncytial giant cells: a case report and review of the literature

Renal cell carcinoma with syncytial giant cells (SGCs) is rare; to our knowledge, there are only 3 cases reported in the English literature. We report on a case that, unlike previous reports, was associated with higher grade renal cell carcinoma and an aggressive behavior. A 63-year-old man with gross hematuria was found to have a large left renal mass and no evidence of metastasis. The nephrectomy specimen contained a 14.8-cm mass that was confined within the renal capsule. Microscopically, a 1.8-cm area of SGCs was noted in a background of clear cell renal cell carcinoma of Fuhrman nuclear grades 2 to 4. The SGCs had voluminous cytoplasm, multiple large nuclei with prominent nucleoli, and focal emperipolesis. Identical to the background mononuclear tumor cells, the SGCs were positive for AE1/AE3, vimentin, and epithelial membrane antigen and negative for CD68, beta-human chorionic gonadotropin, and mucin. Three months after surgery, the patient developed metastases in the liver, right kidney, and lungs.

Collecting duct carcinoma exhibiting diastase-resistant PAS-positive globular cytoplasmic inclusions and rhabdoid features arising in adult polycystic kidney disease: a case report

A 76-year-old man complained of lumbago, and a subsequent detailed examination revealed a mass in the left kidney. Macroscopically, multiple cysts were recognized in the bilateral kidney; the tumor proliferated predominantly in the renal medulla and showed a whitish color with focal necrosis and hemorrhage. A histologic examination of the surgically resected tumor showed various growth patterns, such as solid, tubular, and papillary, by tumor cells. The diagnosis of collecting duct carcinoma (CDC) was made. Furthermore, tumor cells contained globular inclusions resembling hyaline globules and large eosinophilic inclusions, resulting in rhabdoid features, in the cytoplasm. Histochemically, globular inclusions were positive for periodic acid-Schiff (PAS) with diastase pretreatment. Immunohistochemically, large esosinophilic inclusions were reactive for vimentin. Although these findings are rare in CDCs, they should be recognized in the pathologic spectrum of CDCs. Int J Surg Pathol 12(2):171-177, 2004

Renal cell carcinoma: relevance of pathology

PURPOSE OF REVIEW

Although pathological findings including tumour grade and tumour-node-metastasis stage provide prognostic information, the outcome for patients with renal cell carcinoma is occasionally unpredictable. Many studies have been undertaken to improve prediction of the prognosis of renal cell carcinoma, along with efforts to clarify the pathogenesis of renal cell carcinoma at the molecular level. This article reviews the advances in renal cell carcinoma research relevant to pathology published between 1 May 2002 and 30 April 2003.

RECENT FINDINGS

The establishment of a strict tumour grading system or adding microscopic venous invasion or tumour necrosis is potentially useful for predicting patient outcomes. The contribution of the von Hippel-Lindau-related pathway in early carcinogenesis has been partly revealed with regard to angiogenesis and cell cycle control. Tumour development in renal cell carcinoma can be considered as accumulating heterogenous molecular events related to cytokine production, cell cycle control, anti-apoptotic signal machinery and angiogenesis.

SUMMARY

Finding the target genes related to the von Hippel-Lindau pathway may explain the resistance of chemotherapy, and also provide a clue to finding a novel therapeutic option. Molecular targeting therapy can be applicable after more general molecules leading to tumour development and the metastasis of renal cell carcinoma have been identified.