cyclin-d1 and Adenoma--Oxyphilic

Low-grade oncocytic tumor of the kidney (LOT) is characterized by cytoplasmic eosinophilia and a CK7-positive/CD117-negative immunophenotype. Morphologically, they exhibit overlapping features with oncocytoma and chromophobe renal cell carcinoma. Our aim was to obtain long-term clinical follow-up data, clinicopathological and molecular characteristics, and incidence of LOT. Tissue microarrays were constructed from 574 tumors historically diagnosed as oncocytoma and surgically treated at Mayo Clinic between 1970 and 2012, and immunostained for CK7 and CD117. An extended immunophenotype was obtained on whole slide sections, along with FISH for CCND1 rearrangement status and chromosomal microarray for copy number status. In addition, two cases were retrospectively identified in a set of tuberous sclerosis complex (TSC)-associated neoplasms and three more cases diagnosed on needle core biopsies were obtained during routine clinical practice. Twenty-four cases of LOT were identified among 574 consecutive tumors diagnosed as oncocytoma and treated with partial or radical nephrectomy, corresponding to an incidence of 4.18% of tumors historically diagnosed as oncocytomas, and 0.35% of 6944 nephrectomies performed between 1970 and 2012. Overall, 29 cases of LOT were identified in three clinical settings: sporadic, TSC-associated, and end-stage renal disease (ESRD). Multifocality was seen only in the setting of TSC and ESRD. No metastases attributable to LOT were identified (median follow-up 9.6 years). There were no recurrent arm level copy number changes detected by chromosomal microarray and all tested cases were negative for CCND1 rearrangement by FISH. LOT is an uncommon eosinophilic renal neoplasm with an indolent prognosis that constitutes ∼4% of tumors historically diagnosed as oncocytoma. The morphologic, immunophenotypic, and molecular features of this neoplasm suggest it is a distinct entity of renal neoplasia.

Topics: Adenoma, Oxyphilic; Adult; Aged; Aged, 80 and over; Biomarkers, Tumor; Cyclin D1; Female; Gene Dosage; Gene Rearrangement; Humans; Immunohistochemistry; In Situ Hybridization, Fluorescence; Keratin-7; Kidney Neoplasms; Male; Middle Aged; Neoplasm Grading; Nephrectomy; Proto-Oncogene Proteins c-kit; Retrospective Studies; Time Factors; Treatment Outcome

Renal oncocytoma is the most common benign epithelial renal neoplasm. Several adverse features that would typically increase the stage of renal cell carcinomas are not uncommon in renal oncocytoma, including perinephric, sinus fat, or renal vein invasion. Herein, we report the largest single institutional series of renal oncocytoma with adverse pathologic features. The cohort comprised 50 patients, 38 were men (76%) and 12 were women (24%), with a mean age of 68 years (range, 50-87 years). All cases were diagnosed on nephrectomy specimens. No laterality predilection was noted. The tumors ranged in size from 1.5-15.7 cm (mean, 5.3 cm). Adverse pathologic features included perinephric fat invasion (n = 25; 50%), renal sinus fat invasion (n = 9; 18%), and renal vein invasion (n = 5; 10%). More than one adverse feature was seen in 11 tumors (22%). All tumors showed diffuse reactions to KIT (n = 40; 100%) and cyclin D1 (n = 27; 100%). Keratin 7 highlighted rare (<5%) scattered cells, as well as entrapped renal tubules (n = 21; 100%). Reaction to DOG1 was patchy in three tumors (n = 27; 11%) while reactions to vimentin (n = 31) and Hale colloidal iron special stain (n = 30) were negative. On follow-up, no tumor recurrence or metastasis was observed over a follow-up range of 1-144 months (mean, 54 months; median, 60 months). Our data suggest that adverse pathologic features in renal oncocytoma do not alter their benign course.

Topics: Adenoma, Oxyphilic; Aged; Aged, 80 and over; Cyclin D1; Female; Humans; Keratin-7; Kidney; Kidney Neoplasms; Male; Middle Aged

Renal oncocytomas are benign tumors characterized by a marked accumulation of mitochondria. We report a combined exome, transcriptome, and metabolome analysis of these tumors. Joint analysis of the nuclear and mitochondrial (mtDNA) genomes reveals loss-of-function mtDNA mutations occurring at high variant allele fractions, consistent with positive selection, in genes encoding complex I as the most frequent genetic events. A subset of these tumors also exhibits chromosome 1 loss and/or cyclin D1 overexpression, suggesting they follow complex I loss. Transcriptome data revealed that many pathways previously reported to be altered in renal oncocytoma were simply differentially expressed in the tumor's cell of origin, the distal nephron, compared with other nephron segments. Using a heuristic approach to account for cell-of-origin bias we uncovered strong expression alterations in the gamma-glutamyl cycle, including glutathione synthesis (increased

Topics: Adenoma, Oxyphilic; Cell Survival; Chromosomes, Human, Pair 1; Cyclin D1; DNA, Mitochondrial; DNA, Neoplasm; Electron Transport Complex I; Female; Gene Expression Profiling; Glutathione; Humans; Kidney Neoplasms; Male; Mitochondria; Neoplasm Proteins

The distinction between chromophobe renal cell carcinoma (ChRCC), clear cell renal cell carcinoma (CRCC) and renal oncocytoma may cause a diagnostic dilemma. The usefulness of DOG1, cyclin D1, CK7, CD117 and vimentin in the differential diagnosis of these renal epithelial tumors was investigated. DOG1 was positive in ChRCC (32 of 32, 100%) and in renal oncocytoma (21 of 21, 100%). In contrast, DOG1 was absent in all CRCC (0 of 30). Cyclin D1 was positive in renal oncocytomas (17 of 21, 81%) but negative in the ChRCC (0/23) and CRCC (0 of 30). CK7 was positive in ChRCC (30 of 32, 94%), but was negative in oncocytoma (only scattered single positive cells), and was only focal positive in two cases of CRCC. CD117 was expressed in 88% of ChRCC (28 of 32), 86% of renal oncocytoma (18 of 21), and was negative in all CRCC (0 of 30). Twenty-six of the 30 cases of CRCC were positive (87%) for vimentin with prominent membrane staining patterns. All 23 chromophobe carcinomas were negative for vimentin and 15 of 21 oncocytomas demonstrated focal vimentin positivity, but less than 10%. The above results demonstrate that: (1) DOG1 was very sensitive and specific marker for distinguish ChRCC from CRCC; (2) Cyclin D1 was a useful marker to discriminate between ChRCC and renal oncocytoma; (3) CK7 and CD117 were useful markers to distinguish ChRCC from renal oncocytoma and CRCC. (4) Vimentin was helpful for distinguishing clear cell RCC from chromophobe and oncocytoma (87% of clear cell RCC positive, negative in chromophobe, only focally positive in oncocytoma). (5) CK8/18, CK19, CD10, β-catenin and E-cadherin could not be used to distinguish ChRCC from renal oncocytoma and CRCC.

Topics: Adenoma, Oxyphilic; Anoctamin-1; Biomarkers, Tumor; Carcinoma, Renal Cell; Chloride Channels; Cyclin D1; Diagnosis, Differential; Humans; Immunohistochemistry; Keratin-7; Kidney Neoplasms; Neoplasm Proteins; Proto-Oncogene Proteins c-kit; Vimentin

Oncocytomas are predominantly benign neoplasms possessing pathogenic mitochondrial mutations and accumulation of respiration-defective mitochondria, characteristics of unknown significance. Using exome and transcriptome sequencing, we identified two main subtypes of renal oncocytoma. Type 1 is diploid with CCND1 rearrangements, whereas type 2 is aneuploid with recurrent loss of chromosome 1, X or Y, and/or 14 and 21, which may proceed to more aggressive eosinophilic chromophobe renal cell carcinoma (ChRCC). Oncocytomas activate 5' adenosine monophosphate-activated protein kinase (AMPK) and Tp53 (p53) and display disruption of Golgi and autophagy/lysosome trafficking, events attributed to defective mitochondrial function. This suggests that the genetic defects in mitochondria activate a metabolic checkpoint, producing autophagy impairment and mitochondrial accumulation that limit tumor progression, revealing a novel tumor-suppressive mechanism for mitochondrial inhibition with metformin. Alleviation of this metabolic checkpoint in type 2 by p53 mutations may allow progression to eosinophilic ChRCC, indicating that they represent higher risk.

Topics: Adenoma, Oxyphilic; AMP-Activated Protein Kinases; Autophagy; Carcinoma, Renal Cell; Cathepsins; Cell Transformation, Neoplastic; Cyclin D1; DNA Copy Number Variations; Female; Golgi Apparatus; Humans; Karyotype; Kidney; Kidney Neoplasms; Lysosomal Membrane Proteins; Lysosomes; Male; Metformin; Mitochondria; Sequence Analysis, RNA; Transcriptome; Tumor Suppressor Protein p53

Thyroid follicular neoplasms are the most common tumors of the thyroid. The criterion for their malignancy is evidence of capsular or vascular invasion, which makes preoperative diagnosis difficult. The poorly differentiated thyroid carcinoma entity was introduced by World Health Organization in its 2004 classification with an incidence still poorly known. We found 356 follicular neoplasms treated between 1990 and 2006. Among these tumor patients, adenomas were more common in women than in men (3.6:1), but carcinomas differed little with respect to gender (1.2:1). All follicular carcinomas (n=39), atypical adenomas (n=6), and oxyphilic adenomas (n=15) were included in the study, as well as 30 consecutive conventional follicular adenomas. Five tumors were reclassified as poorly differentiated follicular thyroid carcinomas, representing 13% of carcinomas in this unselected material. Predictors of malignancy were high proliferation index (PI) by MIB-1 (p<0.001), large tumor size (p<0.001), and old age (p=0.006). High PI was also a marker of worse prognosis in malignant tumors. Oxyphilic tumor cells were more frequent in carcinomas than in adenomas; however, among carcinomas, they were non-prognostic. Probability for malignancy is thus greater in a male patient with a large oxyphilic follicular neoplasm. The PI requires evaluation in all follicular thyroid carcinomas to identify poorly differentiated tumors with worse prognosis.

Topics: Adenocarcinoma, Follicular; Adenoma, Oxyphilic; Adult; Aged; Aged, 80 and over; Cyclin D1; Female; Humans; Immunohistochemistry; Male; Middle Aged; Retrospective Studies; Thyroid Neoplasms; Tumor Suppressor Protein p53; Ubiquitin-Protein Ligases

Renal oncocytoma is a benign tumor occurring singly or as multiple synchronous lesions. The histologic features of renal oncocytoma may overlap with those of chromophobe renal cell carcinoma. Chromosomal translocations involving the CCND1 locus at 11q13 and overexpression of cyclin D1 occur in a subset of renal oncocytomas. We evaluated a series of 63 renal oncocytomas and 36 chromophobe renal cell carcinomas and assessed the clinical features, cyclin D1 overexpression by immunohistochemistry, and alterations of the CCND1 gene by fluorescence in situ hybridization. All 36 chromophobe renal cell carcinomas were negative for cyclin D1 overexpression and alterations of CCND1. Of the 63 renal oncocytomas, 21 (33%) showed cyclin D1 overexpression. Of 21 renal oncocytomas with cyclin D1 overexpression, a CCND1 rearrangement was detected in 12 (57%). A CCND1 rearrangement was also identified in 1 (2%) of the 42 renal oncocytomas without cyclin D1 overexpression. Of 42 renal oncocytomas without cyclin D1 overexpression, 16 (38%) were from patients with multiple renal oncocytomas at nephrectomy. Of 21 renal oncocytomas with cyclin D1 overexpression, only 1 (5%) patient had multiple renal oncocytomas (P = .006). Of the 25 patients whose original tumor showed no cyclin D1 overexpression, 8 (32%) developed a subsequent renal oncocytoma. None of 15 patients whose original tumor showed cyclin D1 overexpression had a subsequent renal oncocytoma (P = .016). The findings of this study suggest that renal oncocytomas lacking cyclin D1 overexpression may be associated with the development of multiple renal oncocytomas and that these patients are more likely to develop subsequent renal oncocytomas suggesting the need for more frequent clinical for these patients and little need for follow-up in patients with renal oncocytomas overexpressing cyclin D1. The data also show that cyclin D1 overexpression and CCND1 rearrangements by fluorescence in situ hybridization are absent in chromophobe renal cell carcinoma, suggesting that these are useful when differentiating between renal oncocytoma and chromophobe renal cell carcinoma.

Topics: Adenoma, Oxyphilic; Carcinoma, Renal Cell; Case-Control Studies; Chromosomes, Human, Pair 11; Cyclin D1; Cytogenetic Analysis; Diagnosis, Differential; Female; Gene Rearrangement; Humans; Immunohistochemistry; In Situ Hybridization, Fluorescence; Karyotyping; Kidney Neoplasms; Male; Nephrectomy; Translocation, Genetic; Tumor Cells, Cultured

Thyroid fine-needle aspiration (FNA) samples that feature a follicular-patterned, monotonous Hurthle (oncocytic) cell population cannot be diagnosed reliably. The authors of this report recently identified cyclin D3 overexpression on histologic sections of Hurthle cell carcinoma. In this study, they assessed the diagnostic value of cyclin D3 immunohistochemistry added to routine cytology.. Fifty-one FNA samples that were suspicious for Hurtle cell neoplasia and that had histologic follow-up (19 malignant cases) were examined. Cyclin D3 expression levels were evaluated in cell block preparations and were compared with levels of the closely related cyclin D1 protein.. Greater than 25% positive cells were used as the cutoff point, as suggested by previous studies. Cyclin D1 and cyclin D3 were highly specific (100% for both) and fairly accurate (75% and 92%, respectively) in distinguishing between benign and malignant oncocytic lesions; the positive predictive value (PPV) for each was 100%. However, both cyclins D1 and D3 had low sensitivity (32% and 79%, respectively) and low negative predictive value (NPV) (71% and 89%, respectively). In contrast, by adopting balanced receiver operating characteristic-derived positive cutoff values, cyclin D1 (>or=6.5%) and cyclin D3 (>or=7.5%) were found to be highly sensitive (100% for both) and accurate (90% and 94%, respectively); and the NPV was 100% for both. In contrast, cyclins D1 and D3 had low specificity (84% and 91%, respectively) and a low PPV (79% and 86%, respectively); however, these values improved in samples that were positive for both cyclins (sensitivity, 100%; specificity, 94%; PPV, 90%; NPV, 100%; and accuracy, 96%).. Cyclin D3 increased the suspicion of malignancy in indeterminate oncocytic lesions; its diagnostic performance depended on the cutoff point used and was enhanced further when combined with cyclin D1.

Topics: Adenoma, Oxyphilic; Adolescent; Adult; Aged; Biomarkers, Tumor; Biopsy, Fine-Needle; Cyclin D1; Cyclin D3; Female; Gene Amplification; Humans; Immunohistochemistry; Male; Middle Aged; Sensitivity and Specificity; Thyroid Neoplasms

We report the case of a 43-year-old male with multiple tumor foci showing microscopic features of chromophobe renal carcinoma (ChRCC) arising in an oncocytoma. Conventional cytogenetics of fresh tumor cells and fluorescence in situ hybridization (FISH) revealed the following abnormal karyotype: 46,XY,der(8)ins(8;11)(p?;q13),der(11)ins(8;11)inv(11)(q12?p15) with CCND1 (11q13) rearrangement. To our knowledge, chromosome 8 has not been reported as a partner involved in structural rearrangements of 11q13 in oncocytomas. FISH in paraffin tissue sections revealed a rearrangement of CCND1 (11q13) in the oncocytoma cells. The multiple foci of chromophobe carcinoma presented multiple copies of CCND1, suggesting that they represented a transformation from oncocytoma into ChRCC. There was immunohistochemical overexpression of CCND1 in both oncocytoma and chromophobe carcinoma cells. In this case, the correlation of the microscopic findings with changes in CCND1 gene associated to CCND1 overexpression in both components suggest that the ChRCC would have originated from the preexisting oncocytoma. It is not possible to detect, by cytogenetic techniques alone, if the ChRCC component have also the CCND1 rearrangement in addition to the detected polysomy. FISH techniques on paraffin tissue sections may help to identify genetic aberrations such as CCND1 rearrangement in order to establish a diagnosis of oncocytoma.

Topics: Adenoma, Oxyphilic; Adult; Carcinoma, Renal Cell; Cell Transformation, Neoplastic; Chromosome Banding; Chromosomes, Human, Pair 11; Chromosomes, Human, Pair 8; Cyclin D1; Humans; Immunohistochemistry; In Situ Hybridization, Fluorescence; Karyotyping; Kidney Neoplasms; Male

Two groups of renal oncocytomas have been cytogenetically defined by the loss of one or both of chromosomes Y and 1 or by structural rearrangement involving 11q12~q13. We report five renal oncocytomas with structural chromosomal rearrangements involving 11q13 with previously unreported partner chromosomes (namely, 1, 6, and 7). For two of the five cases, a t(6;11)(p21;q13) translocation was revealed; the others had t(1;11)(p13;q13), t(7;11)(q11.2;q13), and t(5;11)(q35; q13). Fluorescence in situ hybridization confirmed translocation of CCND1 at 11q13 to partner chromosomes 5, 6, and 7. Overexpression of cyclin D1, the protein product of CCND1, was detected in three of the five cases (60%) by means of immunohistochemical staining of formalin-fixed, paraffin-embedded tumor sections. In three cases for which fresh tissue was available, Southern blot analysis using the MDL-5 probe for the BCL1 breakpoint did not reveal rearrangement of BCL1. In addition, six consecutive renal oncocytomas diagnosed at our institution between 1999 and 2002 whose karyotypes did not show 11q13 translocations were all negative for cyclin D1 overexpression under immunohistochemical analysis. The findings of CCND1 rearrangement with FISH and correlation with cyclin D1 overexpression under immunohistochemical analysis suggest that cyclin D1 alterations play a role in the subset of renal oncocytomas with 11q translocations, although other genes may also be involved.

Topics: Adenoma, Oxyphilic; Adult; Aged; Blotting, Southern; Chromosome Aberrations; Chromosomes, Human, Pair 11; Cyclin D1; Female; Humans; Immunohistochemistry; In Situ Hybridization, Fluorescence; Karyotyping; Kidney Neoplasms; Male; Middle Aged; Molecular Probes

Oncocytomas are typically benign epithelial tumors whose predominant feature is a massive accumulation of mitochondria in the cytoplasm. With the goal of identifying genes controlling mitochondrial proliferation, we studied three oncocytomas belonging to the cytogenetic subgroup with 11q13 rearrangements. Fluorescence in situ hybridization using bacterial artificial chromosome (BAC) clones showed that the 11q13 breakpoints in all three tumors were near the CCND1 (previously BCL1) gene and did not disrupt any other known gene. The rearrangement in one tumor consisted of a segmental duplication that included 11q13, suggesting that known mitochondrially targeted genes immediately distal to CCND1 may be involved in oncocytic proliferation.

Topics: Adenoma, Oxyphilic; Chromosome Aberrations; Chromosome Mapping; Chromosomes, Human, Pair 11; Cyclin D1; Humans; In Situ Hybridization, Fluorescence; Kidney Neoplasms; Molecular Probes

Recent studies have indicated that numerical chromosomal abnormalities including changes in p53 and cyclin D1 may be involved in Hurthle cell tumorigenesis. We analyzed a series of Hurthle cell neoplasms of the thyroid to evaluate the diagnostic and prognostic utility of numerical anomalies by DNA fluorescent probes for cyclin D1 and p53 gene loci and chromosomes 5, 7, 11, 12, 17, and 22. Interphase fluorescence in situ hybridization (FISH) analysis was performed on paraffin-embedded tissue sections from 10 Hurthle cell adenomas, 19 Hurthle cell carcinomas, and 7 normal thyroid tissues used as controls. Directly labeled fluorescent DNA probes for the centromere region of chromosomes 7, 11, 12, and 17 and locus-specific probes for chromosomes 5 and 22, cyclin D1, and p53 were utilized for dual-probe hybridizations. Sixty percent (6 of 10) Hurthle cell adenomas and 63% (12 of 19) Hurthle cell carcinomas showed chromosome gains. Twenty percent (2 of 10) Hurthle cell adenomas and 26% (5 of 19) Hurthle cell carcinomas showed chromosome losses. Normal thyroid tissues used as controls showed no chromosomal abnormalities. Among Hurthle cell tumors with chromosomal abnormalities, adenomas averaged 2.7 gains and 0.3 losses per case, and carcinomas averaged 3.3 gains and 0.6 losses per case. The two adenomas with chromosome losses each showed loss of one chromosome, whereas the five carcinomas with losses averaged 1.8 losses per case. Chromosome 22 was the most common loss identified, occurring in three of the 11 patients who died of disease. These results indicate that chromosomal imbalances as gains are common in both benign and malignant Hurthle cell neoplasms, but Hurthle cell carcinomas tend to have more chromosome losses than adenomas. Among Hurthle cell carcinomas in this study, chromosome losses were identified only from patients who died of disease. The loss of chromosome 22 may have prognostic value in Hurthle cell carcinoma of the thyroid.

Topics: Adenoma, Oxyphilic; Adult; Aged; Aged, 80 and over; Chromosome Aberrations; Chromosome Disorders; Chromosome Mapping; Cyclin D1; Female; Gene Dosage; Humans; In Situ Hybridization, Fluorescence; Interphase; Male; Middle Aged; Prognosis; Thyroid Neoplasms; Tumor Suppressor Protein p53

Making a histologic distinction between Hurthle cell adenomas and carcinomas sometimes may be difficult. We analyzed a series of Hurthle cell lesions to determine whether specific histologic features and expression of Ki67 and cyclin D1 could be useful in distinguishing Hurthle cell adenomas from carcinomas. Formalin-fixed, paraffin-embedded tissues from 128 Hurthle cell neoplasms, including 59 adenomas; 55 carcinomas; and 14 tumors classified as neoplasms of uncertain malignant behavior (UMB), which had equivocal capsular invasion but no vascular invasion, were analyzed for expression of Ki67 and cyclin D1 by immunostaining. The distribution of immunoreactivity for Ki67 with antibody MIB-1 was analyzed by quantifying the percentage of positive nuclei that was expressed as the labeling index. None of the patients with adenomas or UMB tumors developed recurrent or metastatic disease after a mean follow-up of 7.8 and 7.9 years, respectively. Of the 55 patients with Hurthle cell carcinoma, 19 were associated with metastatic disease, 13 of whom died with disease. No patient with a Hurthle cell carcinoma without vascular invasion developed metastatic disease. The mean tumor size for Hurthle cell carcinomas (4.8 cm) was significantly larger than that of Hurthle cell adenomas (3.1 cm) or UMB tumors (3.7 cm). No patient with a Hurthle cell tumor smaller than 3.5 cm developed metastatic disease, even when vascular invasion was present. The Ki67 labeling index in Hurthle cell carcinomas (10.0 +/- 1.2) was 3-fold higher than in Hurthle cell adenomas (3.2 +/- 0.3). The Ki67 labeling index in the UMB group was 5.0 +/- 0.7. Cyclin D1 showed diffuse nuclear staining in 1 of the 59 (1.7%) Hurthle cell adenomas, in 10 of the 55 (18%) Hurthle cell carcinomas, and in none of the UMB tumors. In summary, analyses of the cell cycle proteins Ki67 and cyclin D1 in Hurthle cell thyroid neoplasms indicate that these markers may assist in distinguishing some Hurthle cell carcinomas from adenomas. Among the Hurthle cell carcinomas, large tumor size and vascular invasion are associated with clinically aggressive tumors. Our study also suggests that Hurthle cell neoplasms with only equivocal capsular invasion and no vascular invasion should behave in a benign manner.

Topics: Adenocarcinoma; Adenoma, Oxyphilic; Cell Count; Cell Division; Cyclin D1; Female; Humans; Immunoenzyme Techniques; Ki-67 Antigen; Male; Middle Aged; Survival Rate; Thyroid Neoplasms

Cyclin D1 plays an important role in cell cycle progression from G1 to S phase. Cyclin D1 overexpression has been identified in many human neoplasms, including a variety of carcinomas. A systematic study of cyclin D1 expression in renal carcinomas and oncocytomas has not been reported. Ninety-six renal epithelial neoplasms, 78 renal carcinomas (45 clear-cell, 18 papillary, and 15 chromophobe), and 18 oncocytomas were analyzed immunohistochemically using routinely fixed tissue sections and a cocktail of two monoclonal anti-cyclin D1 antibodies. One thousand cells were manually counted, and the percentage of cyclin D1 positive cells was calculated. Fluorescence in situ hybridization studies using chromosome 11 centromeric and 11q13 specific probes were performed on a subset of clear-cell carcinomas and oncocytomas. Cyclin D1 immunoreactivity was observed in 23 (51%) of 45 clear-cell, 5 (28%) of 18 papillary, and 2 (13%) of 15 chromophobe carcinomas. Nine (50%) of 18 oncocytomas were positive for cyclin D1. Cyclin D1 expression in clear-cell carcinomas did not correlate with survival. Fluorescence in situ hybridization studies on eight clear-cell carcinomas and seven oncocytomas revealed normal chromosome 11 number and no evidence of amplification of the 11q13 locus. Thus, cyclin D1 can be immunohistochemically demonstrated in approximately one-half of renal oncocytomas and clear-cell carcinomas and is less frequent in papillary and chromophobe carcinomas. The mechanism of cyclin D1 expression is unknown, but it does not seem to be related to extra copies of chromosome 11 or to gene amplification.

Topics: Adenocarcinoma; Adenocarcinoma, Clear Cell; Adenoma, Oxyphilic; Carcinoma, Papillary; Carcinoma, Renal Cell; Cell Nucleus; Cyclin D1; Disease-Free Survival; Humans; Immunohistochemistry; In Situ Hybridization, Fluorescence; Kidney Neoplasms; Survival Analysis