Macroscopically, renal oncocytomas are solitary, wellcircumscribed, slightly lobulated solid tumors with generally mahogany brown or dark red cut surface. A central scar is frequently observed. Necrosis and hemorrhage are uncommon. Microscopically, tumor cells with abundant, granular cytoplasm are arranged in nests, tubulocystic, solid, or trabecular patterns within edematous, myxomatous or hya...

Sarcomatoid change in renal cell carcinoma is the result of the dedifferentiation of the "parent" tumor into a high-grade malignancy characterized by sarcoma-like features and associated with an accelerated clinical course and poorer prognosis. Any of the renal cell carcinoma subtypes can undergo sarcomatoid dedifferentiation, with the chromophobe variant being the most prone. The present repor...

INTRODUCTION Renal cell carcinomas account for 85% of all renal neoplasms. With the introduction of modern imaging modalities, there has been an increased diagnosis of renal tumors. Recent studies have shown that partial nephrectomy can be as safe as radical nephrectomy for smaller renal tumors. Renal cell carcinomas are usually unilateral, however, they can be bilateral in 2% to 4% of sporadic...

Succinate dehydrogenase (SDH), which is located on the mitochondrial inner membrane, is essential to the Krebs cycle. Mutations of the SDH gene are associated with many tumors, such as renal cell carcinoma, wild type gastrointestinal stromal tumors (WT GISTs) and hereditary paragangliomas/pheochromocytomas. Herein we present a rare case diagnosed as a WT GIST complicated with a renal chromophob...

Birt-Hogg-Dubé syndrome is a rare autosomal dominant genodermatosis that is characterized by the presence of fibrofolliculomas and/or trichodiscomas, pulmonary cysts, spontaneous pneumothorax, and renal tumors. The most common histological types found in renal tumors from patients with the syndrome are oncocytoma-chromophobe carcinoma hybrids and pure forms of chromophobe carcinoma, oncocytic c...

The renal cell carcinomas (RCC), clear cell, papillary, and chromophobe, have recently undergone an unmatched genomic characterization by The Cancer Genome Atlas. This analysis has revealed new insights into each of these malignancies and underscores the unique biology of clear cell, papillary, and chromophobe RCC. Themes that have emerged include distinct mechanisms of metabolic dysregulation ...

We analyzed 19 chromophobe renal cell carcinomas by means of comparative genomic hybridization. Two tumors revealed no numerical abnormalities. In the remaining 17 cases we found loss of entire chromosomes with underrepresentation of chromosome 1 occurring in all 17 cases; loss of chromosomes 2, 10, and 13 in 16 cases; loss of chromosomes 6 and 21 in 15 tumors; and loss of chromosome 17 in 13 c...

Loss of heterozygosity (LOH) at chromosome 3p and inactivation of the VHL gene are associated with the development of conventional renal cell carcinomas (RCCs). Recently, it was suggested that LOH at the FHIT gene at 3p14.2 is an early event in the development of RCC and is characteristic for all types of RCC. We have analyzed 88 conventional, 30 papillary, and 22 chromophobe RCCs for LOH at th...

Tumors arising in and around the hypophyseal fossa can cause symptoms by compression of surrounding structures or, in the case of adenomas arising from the adenohypophysis, by hypersecretion of hormones. Until recently, adenomas of the hypophysis have been classified on the basis of light microscopy into chromophobe, eosinophilic and basophilic. Presently available methods of histochemistry, im...

The presence of myofibroblasts has been elucidated in neoplastic capsules of various organs. In the present article, we examine the presence of myofibroblasts in the capsule of renal cell carcinoma (RCC) and discuss the origin of the myofibroblasts. Nineteen renal tumors (conventional RCC, n=17; chromophobe RCC, n=2) with evident and totally surrounded fibrous capsule were selected. Abundant my...