Search PubMed⌕ Search

Biomedical subjects

John N Eble

Publications and source records attributed to John N Eble.

At least 19 recordsLinked to original sources

Amplifications of EGFR gene and protein expression of EGFR, Her-2/neu, c-kit, and androgen receptor in phyllodes tumor of the prostate.

Phyllodes tumor of the prostate is a rare neoplasm with an unpredictable clinical behavior. It may undergo early recurrence with sarcomatous transformation or may even metastasize. Because targeted therapies have shown great success against several malignancies, there is hope that these same therapies may show similar promise in the treatment of other neoplasms. This study was undertaken to investigate both amplification of the epidermal growth factor receptor (EGFR) gene by fluorescence in situ hybridization and the overexpression of EGFR, Her-2/neu, CD117 (c-kit), and androgen receptor by immunohistochemical staining in a series of 11 phyllodes tumors of the prostate. In the stromal elements, EGFR gene amplification was present in four of 11 tumors and polysomy chromosome 7 was present in two of 11 tumors. No amplification was present in the epithelial components. Only one of 11 tumors had polysomy of chromosome 7 in the epithelial components. Immunohistochemically, in the stromal components, EGFR expression was demonstrable in four of 11 tumors and androgen receptor was demonstrated in six of 10 tumors. Neither Her-2/neu nor c-kit expression was seen in the stromal components of any of the 11 tumors. In the epithelial components, EGFR expression was present in all 11 tumors with strong staining in the basal cell layers and weak or no staining in luminal epithelium; androgen receptor expression was seen in seven of 10 tumors; Her-2/neu was weakly positive in four of 11 tumors; and c-kit expression was present focally and weakly in two of 11 cases with only 2-5% of cells staining. The highest staining intensity and the highest percentage of positively staining cells were seen with EGFR immunostaining in both the stromal and epithelial (mainly basal cells) components. Androgen receptor staining showed the next highest staining intensity and percentage of positive cells in both components. Her-2/neu and c-kit were only weakly or infrequently expressed in the epithelial components of prostatic phyllodes tumors. Our data indicate that EGFR and androgen receptor are frequently and strongly expressed in both epithelial and stromal components of prostatic phyllodes tumors. EGFR gene amplification is frequently present in prostatic phyllodes tumors and may account for one of the mechanisms leading to protein overexpression in some but not all cases. Anti-EGFR and/or antiandrogen agents may be potentially useful for management of patients with tumors expressing EGFR and/or androgen receptor.

Adult↗

Clonal origin of metastatic testicular teratomas.

PURPOSE: Testicular teratomas in adult patients are histologically diverse tumors that frequently coexist with other germ cell tumor (GCT) components. These mixed GCTs often metastasize to retroperitoneal lymph nodes where multiple GCT elements are frequently present in the same metastatic lesion. Neither the genetic relationships among the different components in metastatic lesions nor the relationships between primary and metastatic GCT components have been elucidated. EXPERIMENTAL DESIGN: We examined metastases from 31 patients who underwent primary retroperitoneal lymph node dissection for metastatic testicular GCT. All patients had metastatic mature teratoma with one or more other GCT components. This study included a total of 72 metastatic GCT components and 16 primary GCT components from 31 patients. Genomic DNA samples from each component were prepared from formalin-fixed, paraffin-embedded tissue sections using laser-assisted microdissection. Loss of heterozygosity (LOH) assays for seven microsatellite polymorphic markers on chromosomes 1p36 (D1S1646), 9p21 (D9S171 and IFNA), 9q21 (D9S303), 13q22-q31 (D13S317), 18q22 (D18S543), and 18q21 (D18S60) were done to assess clonality. RESULTS: Twenty-nine of 31 (94%) cases showed allelic loss in one or more components of the metastatic GCTs. Twenty-nine of 31 mature teratomas showed allelic loss in at least one of seven microsatellite polymorphic markers analyzed. The frequency of allelic loss in informative cases of metastatic mature teratoma was 27% (8 of 30) with D1S1646, 34% (10 of 29) with D9S171, 37% (10 of 27) with IFNA, 27% (8 of 30) with D9S303, 46% (13 of 28) with D13S317, 26% (7 of 27) with D18S543, and 36% (10 of 28) with D18S60. Completely concordant allelic loss patterns between the mature teratoma and all of the other metastatic GCT components were seen in 26 of 29 cases in which the mature teratoma component showed LOH. Nearly identical allelic loss patterns were seen in the three remaining cases. In six cases analyzed, LOH patterns of each metastatic component were compared with each GCT component of the primary testicular tumor. In all six cases, each primary and metastatic component showed an identical pattern of allelic loss. CONCLUSION: Our data support the common clonal origin of metastatic mature teratomas with other components of metastatic testicular GCTs and with each component of the primary tumor.

Adolescent↗

Divergent pathway of intestinal metaplasia and cystitis glandularis of the urinary bladder.

Intestinal metaplasia has been proposed to be a precursor lesion of adenocarcinoma in the urinary bladder. CDX2 is a transcription factor that is encoded by a homeotype gene that plays an essential role in the differentiation and proliferation of intestinal epithelial cells. Hepatocyte-specific antigen (Hep) has also been shown to be a useful marker of intestinal metaplasia. Tissues from 46 patients, including 22 cases of intestinal metaplasia of the urinary bladder, 11 cases of typical cystitis glandularis, and 13 cases containing both lesions, were selected and immunohistochemical stains for CDX2, Hep, cytokeratin 20 (CK20), and cytokeratin 7 (CK7) were performed. Nuclear staining for CDX2 was observed in 29 of 35 (83%) cases of intestinal metaplasia of the urinary bladder. In contrast, nuclear staining for CDX2 was not observed in any case of typical cystitis glandularis; however, seven of 24 (29%) cases showed aberrant cytoplasmic expression in a mean of 37% of cells. CK20 was expressed in 28 of 35 (80%) cases of intestinal metaplasia, but was observed in only one of 24 (4%) cases of cystitis glandularis in 15% of cells. CK7 was expressed in only six of 35 (17%) cases of intestinal metaplasia, whereas expression of CK7 was observed in all cases (100%) of typical cystitis glandularis with a mean percentage of positively staining cells of 63%. The mean percentages of positively staining cells in intestinal metaplasia with CDX2, CK20, and CK7 were 55, 49, and 53%, respectively. All examples of both intestinal metaplasia and typical cystitis glandularis were uniformly negative for Hep. In the urinary bladder, intestinal metaplasia and typical cystitis glandularis have sharply contrasting immunoprofiles. Additionally, the absence of Hep staining in intestinal metaplasia of the urinary bladder, despite its morphologic resemblance to normal colonic mucosa and intestinal metaplasia in other organs, may signify the presence of unique metaplastic pathways in the urinary bladder.

Autoantigens↗

Inverted papilloma of the urinary bladder: a molecular genetic appraisal.

Inverted papilloma of urinary bladder is an uncommon urothelial neoplasm. Its relationship to urothelial carcinoma is controversial. Little is known of the genetic abnormalities of inverted papilloma. To better understand its genetics, we analyzed 39 inverted papillomas, including 36 from men and three from women, for loss of heterozygosity (LOH). We examined four polymorphic microsatellite markers located on chromosome 9q32-33(D9S177), chromosome 9p22 (IFNA), chromosome 3p14.2 (D3S1300) and chromosome 17p13.1 (TP53), where genetic alterations occur frequently in urothelial carcinomas. Additionally, the status of inactivation of X-chromosome was examined in three female patients. The frequency of LOH in informative cases was 8% (3 of 37) for D9S177, 10% (4 of 38) for TP53, 8% (3 of 37) for IFNA and 8% (3 of 36) for D3S1300. In the analysis of X-chromosome inactivation, all three cases yielded informative results and one had nonrandom inactivation of X-chromosomes. The monoclonal origin demonstrated in the study of X-chromosome inactivation indicates the clonal process of inverted papilloma; however, the low incidence of LOH supports the view that inverted papilloma in urinary bladder is a benign neoplasm with molecular genetic abnormalities different from those of urothelial carcinoma.

Female↗

Cytokeratin and CD30 expression in dysgerminoma.

Dysgerminoma is a malignant germ cell tumor of the ovary that shares morphological, immunophenotypic, and genetic features with its testicular counterpart, seminoma. Recent evidence supports the hypothesis that seminoma can differentiate into non-seminomatous germ cell tumor types. The progression of these tumors can be measured by their acquisition of the potential to express cytokeratin intermediate filaments, a characteristic specific to epithelial differentiation. Although testicular seminomas have been widely investigated, little is known about cytokeratin or E-cadherin expression in dysgerminomas. We investigated 26 formalin-fixed, paraffin-embedded ovarian dysgerminomas with immunohistochemical stains for CAM5.2, AE1/AE3, epithelial membrane antigen, cytokeratin 7, cytokeratin 20, high-molecular-weight keratin, and E-cadherin. In addition, we investigated the CD30 and vimentin immunoreactivity of these tumors. Immunoreactivity for CAM5.2 and for AE1/AE3 was present in more than 10% of neoplastic cells in 5 (19.2%) of 26 cases and in 2 (7.7%) of 26 cases, respectively. Cytokeratin 7 showed only focal positivity and never showed positive staining in greater than 10% of dysgerminoma cells. E-cadherin staining was positive in 2 cases showing weak membranous immunostaining in more than 10% of cells. Vimentin immunoreactivity was observed in only 2 dysgerminomas, both of which had less than 10% of the neoplastic cells staining. Cytokeratin 20, epithelial membrane antigen, high-molecular-weight keratin, and CD30 were consistently negative in all cases. Our study demonstrates that cytokeratin expression in dysgerminomas is not unusual and is consistent with the hypothesis that dysgerminomas have the capacity to differentiate along epithelial lines. Furthermore, the immunohistochemical staining patterns for cytokeratins, E-cadherin, and CD30 in dysgerminomas need to be considered when assessing differential diagnoses in difficult cases of primary ovarian tumors.

Adolescent↗

Tertiary Gleason pattern 5 is a powerful predictor of biochemical relapse in patients with Gleason score 7 prostatic adenocarcinoma.

PURPOSE: In radical prostatectomy specimens Gleason score 7 is among the most commonly assigned scores for prostate carcinoma accounting for 30% to 50% of cases. Gleason score 7 is different from other more differentiated prostate carcinomas (tumors of Gleason scores 5 and 6) with a significantly worse outcome and higher rate of recurrence. Nonetheless, Gleason score 7 tumors are heterogeneous. In this study we examined the differences in clinical outcome between primary Gleason grade 3 and 4 tumors in patients who underwent radical prostatectomy, and determined the influence of tertiary Gleason pattern 5 on patient outcome. MATERIALS AND METHODS: A total of 504 patients underwent radical prostatectomy for prostate cancer and 228 of the patients (45%) had a Gleason score of 7. Cases were analyzed for a variety of clinical and pathological parameters. The influence of primary Gleason pattern and tertiary Gleason pattern 5 on patient outcome was assessed in the Cox regression model. RESULTS: Among 228 patients with Gleason score 7 prostatic adenocarcinoma, 91 (40%) had a primary Gleason pattern 4 and 137 (60%) had primary Gleason pattern 3. Patients of the former group were more likely to have a higher pathological stage (p = 0.003), more likely to have PSA recurrence (p = 0.02) and more likely to have a tertiary Gleason pattern 5 (p <0.0001). A total of 37 (41%) patients with primary Gleason 4 had a tertiary Gleason pattern 5, whereas only 13 (9%) patients with primary Gleason 3 had a tertiary Gleason pattern 5. In the Cox regression model controlling for tumor stage and surgical margin status, the primary Gleason pattern was not an independent predictor of PSA recurrence (p = 0.80), whereas the presence of tertiary Gleason pattern 5 was a significant predictor of PSA recurrence (hazard ratio 2.10, 95% CI 1.24-3.55, p = 0.006). Five-year PSA recurrence-free survival was 70% for patients without a tertiary Gleason pattern 5 compared to 19% for those patients with a tertiary Gleason pattern 5. CONCLUSIONS: Among patients with Gleason score 7, primary Gleason grade 4 indicates a likelihood of higher tumor stage and higher probability of PSA recurrence than does primary pattern 3. However, it does not independently predict a worse outcome after controlling for other known prognostic parameters associated with disease progression. Regardless of whether the primary Gleason pattern is 3 or 4, a tertiary Gleason pattern 5 is the strongest predictor of a worse outcome in patients with Gleason grade 7 prostatic adenocarcinoma. Therefore, tertiary pattern 5 should be reported in radical prostatectomy specimens.

Adenocarcinoma↗

Renal mucinous tubular and spindle carcinoma lacks the gains of chromosomes 7 and 17 and losses of chromosome Y that are prevalent in papillary renal cell carcinoma.

Mucinous tubular and spindle cell carcinoma of the kidney is an uncommon, distinctive neoplasm characterized by the proliferation of cuboidal and spindle cells arranged in tubular or sheet-like arrays, typically with a mucinous or myxoid background. The most important differential diagnostic consideration of mucinous tubular and spindle cell carcinoma is papillary renal cell carcinoma, type 1, with sarcomatoid transformation. The aim of our study is to investigate the pattern of possible gains or losses of chromosomes 7, 17 and Y in 10 mucinous tubular and spindle cell carcinomas with interphase fluorescence in situ hybridization (FISH). Four-micron sections were obtained from paraffin blocks representative of the tumors and including adjacent non-neoplastic renal parenchyma from 10 patients. The patients' ages ranged from 20 to 80 years (mean: 62 years); eight were female, while two were male. FISH analysis was performed with centromeric probes for chromosomes 7, 17 and Y. One hundred fifty to 200 nuclei from each case were scored for hybridization signals and non-neoplastic parenchyma served as control tissue. We found that renal mucinous tubular and spindle carcinoma lacks the gains of chromosomes 7 and 17 and losses of chromosome Y that are typical of papillary renal cell carcinoma. FISH analysis with centromeric probes for these chromosomes is potentially helpful in differentiating mucinous tubular and spindle cell carcinomas from papillary renal cell carcinomas.

Adenocarcinoma, Mucinous↗

Chromosome 12p abnormalities in dysgerminoma of the ovary: a FISH analysis.

Dysgerminoma is the most common malignant ovarian germ cell tumor and shares histological and immunophenotypical features with its testicular counterpart, seminoma. Chromosome 12p abnormalities are genetic hallmarks of testicular seminomas. Little is known about these genetic changes in dysgerminoma. We performed dual color fluorescence in situ hybridization (FISH) analyses with a centromeric alpha-satellite probe for chromosome 12 and a subtelomeric probe for 12p on paraffin-embedded tissue sections from 21 dysgerminomas and two gonadoblastomas. Chromosome 12p abnormalities were detected in 81% of dysgerminomas. In all, 57% of cases had only isochromosome 12p and 5% had only 12p overrepresentation. In all, 19% had both isochrome 12p and 12p overrepresentation. Gonadoblastomas were negative for isochromosome 12p or 12p overrepresentation. Chromosome 12p abnormalities are common in dysgerminoma of the ovary. FISH analyses for chromosome 12p abnormalities may be a useful diagnostic adjunct for confirming the diagnosis of dysgerminoma and for distinguishing it from nongerm cell malignancies that enter into the differential diagnosis.

Adolescent↗

Acquired cystic disease-associated renal tumors: an immunohistochemical and fluorescence in situ hybridization study.

End-stage renal disease is associated with an increased incidence of renal cell neoplasms. Among these, recent studies have identified tumors with unusual histological patterns that do not fit into the categories recognized in the current classification system. These tumors often occur in kidneys with acquired cystic disease and are composed mainly of large eosinophilic cells arranged in solid, cribriform, acinar, or papillary patterns. They also contain deposits of calcium oxalate crystals. We investigated three eosinophilic epithelial tumors arising in kidneys with acquired cystic disease from three patients. Each of the tumors was composed of large eosinophilic cells arranged in solid, acinar, or tubulocystic architecture. Deposits of calcium oxalate crystals were present in each tumor. Hale's colloidal stain showed a positive cytoplasmic reaction in one of the neoplasms. Immunohistochemistry displayed positive results for CD10 (3/3), AE1/AE3 (3/3), alpha-methylacyl-CoA racemase (2/3), CAM5.2 (2/3), and vimentin (1/3). Reactions for epithelial membrane antigen, cytokeratin 7, and high molecular weight cytokeratin (34betaE12) were negative. Fluorescence in situ hybridization analysis showed no losses or gains of chromosomes 1, 2, 6, 10, or 17 in one tumor. There were gains of chromosomes 1, 2, and 6 in two tumors. One of these tumors also showed gains of chromosome 10. Eosinophilic renal cell tumors associated with acquired cystic disease have immunophenotypes and genetic profiles distinct from the renal cell neoplasms recognized in the current classification of renal cell neoplasia, and should be considered as a distinct clinicopathologic entity in the spectrum of renal cell neoplasia.

Adenocarcinoma↗

Invasion of fat justifies assignment of stage pT3a in prostatic adenocarcinoma.

AIMS: The detection of invasive cancer cells within the adipose tissue of needle biopsies has been regarded as bona fide evidence of extraprostatic tumour extension, and as a consequence may influence subsequent patient management. However, the identification of rare intraprostatic fat from recent reports involving series of autopsies has challenged this practice principle. We examined totally embedded, whole-mounted radical prostatectomy specimens in order to determine the occurrence of intraprostatic fat in prostatic tissue, and further, to assess the importance of the identification of fat infiltration by neoplastic cells in needle biopsy specimens as a marker of extraprostatic infiltration by tumour. METHODS: Between 2000 and 2003, 313 consecutive patients underwent radical prostatectomy for clinically localised prostate cancer in the Indiana University Hospital. All radical prostatectomy specimens were completely embedded and whole mounted for histological examination. All slides were reviewed and evaluated for the presence or absence of intraprostatic fat. Other pathological characteristics of prostate cancer were also assessed and clinical data were gathered by a review of patient charts. RESULTS: The mean age of patients was 60 years. None of these 313 radical prostatectomy specimens revealed any adipose tissue components within the most peripheral boundary of normal prostatic acini in the prostate. CONCLUSIONS: We found no evidence of intraprostatic fat and our findings suggest that, at best, the occurrence of fat within the prostate is of extreme rarity. Accordingly, the finding of carcinoma invading adipose tissue in needle biopsies should continue to be considered as extraprostatic extension and stage pT3a assigned.

Adenocarcinoma↗

Adrenal myelolipomas show nonrandom X-chromosome inactivation in hematopoietic elements and fat: support for a clonal origin of myelolipomas.

Myelolipomas are defined as mature fat associated with hematopoietic elements, often found in the adrenal gland. The question of whether the hematopoietic cells are truly "normal" has not been evaluated extensively. In this study, we evaluated histologic, immunohistochemical features and comparisons of X-chromosome inactivation patterns in 19 myelolipomas. Formalin-fixed, paraffin-embedded tissue from 19 myelolipomas was stained with hematoxylin and eosin and immunostained with monoclonal antibodies against CD138, CD34, CD117, CD42a, hemoglobin, myeloperoxidase, collagen IV, and nerve growth factor receptor. Histologic evaluation included estimates of overall cellularity of hematopoietic tissue, estimates of cellularity in the areas of highest concentration of hematopoietic tissue, myeloid to erythroid ratio, and numbers of megakaryocytes. X-chromosome inactivation analysis was performed on myelolipomas from 11 female patients by polymerase chain reaction. Myelolipomas showed wide variation in cellularity within the lesion (5% to 90%) with no correlation with the patient's age. All the myelolipomas demonstrated normal trilineage hematopoiesis and cellular morphology, with few early myeloid precursors, as evidenced by negativity for CD117 and only rare positivity for CD34 antibodies. Most of the myelolipomas (14/18) had markedly increased megakaryocytes compared with normal marrows. The majority of myelolipomas also had a stromal composition and vascular patterns that were different from those of normal bone marrow. X-chromosome inactivation studies demonstrated nonrandom X-chromosome inactivation in 8/11 myelolipomas from female patients. Myelolipomas are morphologically different from the normal bone marrow. The majority of myelolipomas also have nonrandom X-chromosome inactivation, suggesting a clonal origin for these tumors.

Adipose Tissue↗

Clonal origin of lymph node metastases in bladder carcinoma.

BACKGROUND: Evidence of genetic heterogeneity within urothelial carcinomas of the bladder has raised questions about the clonal origin of urothelial carcinoma and its metastases. High-grade urothelial carcinoma of the bladder frequently metastasizes to multiple regional lymph nodes in the pelvis. Whether or not these multiple lymph node metastases originate from the same tumor clone is uncertain. Molecular analysis of microsatellite alterations and X-chromosome inactivation status of distinct tumor cell populations from the same patient may further our understanding of the genetic basis of carcinoma progression and metastasis. METHODS: The authors examined 24 patients who underwent radical cystectomy for urothelial carcinoma. All patients had multiple (from two to four) lymph node metastases. Genomic DNA samples were prepared from formalin fixed, paraffin embedded tissue sections using laser-assisted microdissection. Loss of heterozygosity (LOH) assays for 3 microsatellite polymorphic markers on chromosome 9p21 (D9S171, region of putative tumor suppressor gene p16), 9q32 (D9S177, putative tumor suppressor gene involved in urothelial carcinoma tumorigenesis), and 17p13 (TP53, the p53 locus) were performed. In addition, X-chromosome inactivation analysis was performed in primary tumors and metastases from 10 female patients. RESULTS: In total, 79 tumors were analyzed. The overall frequency of allelic loss was 67% (16 of 24 tumors) in the primary urothelial carcinomas and 79% (19 of 24 tumors) in the metastatic carcinomas. The primary urothelial carcinoma showed LOH at the D9S171, D9S177, and TP53 loci in 39% (9 of 23 tumors), 30% (6 of 20 tumors), and 30% (7 of 23 tumors) of informative samples, respectively. LOH in > or = 1 lymph node metastases was seen at the D9S171, D9S177, and TP53 loci in 35% (8 of 23 tumors), 45% (9 of 20 tumors), and 48% (11 of 23 tumors) of informative samples, respectively. Eleven tumors demonstrated identical allelic loss patterns at all DNA loci both in the primary carcinoma and in all corresponding lymph node metastases. Three tumors showed allelic loss in the metastatic carcinoma but not in its matched primary carcinoma. Six tumors demonstrated a different LOH pattern in each of its lymph node metastases. Clonality analysis showed the same pattern of nonrandom X-chromosome inactivation both in the primary urothelial carcinoma and in all of the lymph node metastases in five of nine informative tumors studied. Four tumors showed a random pattern of X-chromosome inactivation in both the primary carcinoma and in the metastases. CONCLUSIONS: LOH and X-chromosome inactivation assays showed that multiple lymph node metastases and matched primary urothelial carcinomas of the bladder had the same clonal origin, suggesting that the capability for metastasis often arises in only a single clonal population in the primary tumor. The variable LOH patterns observed in some of the tumors likely reflect genetic divergence during the clonal evolution of urothelial carcinoma.

Adult↗

Molecular genetic evidence for the independent origin of multifocal papillary tumors in patients with papillary renal cell carcinomas.

PURPOSE: In patients with papillary renal cell carcinoma, it is not uncommon to find two or more anatomically distinct and histologically similar tumors at radical nephrectomy. Whether these multiple papillary lesions result from intrarenal metastasis or arise independently is unknown. Previous studies have shown that multifocal clear cell renal cell carcinomas express identical allelic loss and shift patterns in the different tumors within the same kidney, consistent with a clonal origin. However, similar clonality assays for multifocal papillary renal cell neoplasia have not been done. Molecular analysis of microsatellite and chromosome alterations and X-chromosome inactivation status in separate tumors in the same patient can be used to study the genetic relationships among the coexisting multiple tumors. EXPERIMENTAL DESIGN: We examined specimens from 21 patients who underwent radical nephrectomy for renal cell carcinoma. All patients had multiple separate papillary lesions (ranging from 2 to 5). Eighteen patients had multiple papillary renal cell carcinomas. Seven had one or more papillary renal cell carcinomas with coexisting papillary adenomas. Genomic DNA samples were prepared from formalin-fixed, paraffin-embedded tissue sections using laser-capture microdissection. Loss of heterozygosity assays were done for six microsatellite polymorphic markers for putative tumor suppressor genes on chromosomes 3p14 (D3S1285), 7q31 (D7S522), 9p21 (D9S171), 16q23 (D16S507), 17q21 (D17S1795), and 17p13 (TP53). X-chromosome inactivation analyses were done on the papillary kidney tumors from three female patients. Fluorescence in situ hybridization analysis was done on the tumors of selected patients showing allelic loss at loci on chromosome 7 and/or chromosome 17. RESULTS: Twenty of 21 (95%) cases showed allelic loss in one or more of the papillary lesions in at least one of the six polymorphic markers analyzed. A concordant allelic loss pattern between each coexisting kidney tumor was seen in only 1 of 21 (5%) cases. A concordant pattern of nonrandom X-chromosome inactivation in the coexisting multiple papillary lesions was seen in two of three female patients. A discordant pattern of X-chromosome inactivation was seen in the tumors of the other female patient. Fluorescence in situ hybridization showed that the majority of tumors analyzed had gains of chromosomes 7 and 17. Two patients had one tumor with chromosomal gain and another separate tumor that did not. CONCLUSION: Our data suggest that, unlike multifocal clear cell renal cell carcinomas, the multiple tumors in patients with papillary renal cell carcinoma arise independently. Thus, intrarenal metastasis does not seem to play an important role in the spread of papillary renal cell carcinoma, a finding that has surgical, therapeutic, and prognostic implications.

Adult↗

Clonal divergence and genetic heterogeneity in clear cell renal cell carcinomas with sarcomatoid transformation.

BACKGROUND: Approximately 5% of clear cell renal cell carcinomas contain components with sarcomatoid differentiation. It has been suggested that the sarcomatoid elements arise from the clear cell tumors as a consequence of clonal expansions of neoplastic cells with progressively more genetic alterations. Analysis of the pattern of allelic loss and X-chromosome inactivation in both the clear cell and sarcomatoid components of the same tumor allows assessment of the genetic relationship of these tumor elements. METHODS: The authors of the current study examined the pattern of allelic loss in clear cell and sarcomatoid components of renal cell carcinomas from 22 patients who had tumors with both components. DNA samples were prepared from formalin-fixed, paraffin-embedded renal tissue sections using laser-capture microdissection. Five microsatellite polymorphic markers for putative tumor suppressor genes on 5 different chromosomes were analyzed. These included D3S1300 (3p14), D7S522 (7q31), D8S261 (8p21), D9S171 (9p21), and TP53 (17p13). In addition, X-chromosome inactivation analysis was performed in 14 tumors from female patients. RESULTS: The clear cell components showed loss of heterozygosity (LOH) at the D3S1300, D7S522, D8S261, D9S171, and TP53 loci in 18% (4/22), 18% (4/22), 50% (10/20), 15% (3/20), and 20% (4/20) of informative cases, respectively. LOH in the sarcomatoid components was seen at the D3S1300, D7S522, D8S261, D9S171, and TP53 loci in 18% (4/22), 41% (9/22), 70% (14/20), 35% (7/20), and 20% (4/20) of informative cases, respectively. Six cases demonstrated an LOH pattern in the clear cell component that was not seen in the sarcomatoid component. Different patterns of allelic loss were seen in the clear cell and sarcomatoid components in 15 cases. Clonality analysis showed the same pattern of nonrandom X-chromosome inactivation in both clear cell and sarcomatoid components in 13 of the 14 cases studied. One case showed a random pattern of X-chromosome inactivation. CONCLUSION: X-chromosome inactivation analysis data suggest that both clear cell and sarcomatoid components of renal cell carcinomas are derived from the same progenitor cell. Different patterns of allelic loss in multiple chromosomal regions were observed in clear cell and sarcomatoid components from the same patient. This genetic heterogeneity indicates genetic divergence during the clonal evolution of renal cell carcinoma.

Adult↗

Molecular evidence supporting field effect in urothelial carcinogenesis.

PURPOSE: Human urothelial carcinoma is thought to arise from a field change that affects the entire urothelium. Multifocality of urothelial carcinoma is a common finding at endoscopy and surgery. Whether these coexisting tumors arise independently or are derived from the same tumor clone is uncertain. Molecular analysis of microsatellite alterations and X-chromosome inactivation status in the cells from each coexisting tumor may further our understanding of urothelial carcinogenesis. EXPERIMENTAL DESIGN: We examined 58 tumors from 21 patients who underwent surgical excision for urothelial carcinoma. All patients had multiple separate foci of urothelial carcinoma (two to four) within the urinary tract. Genomic DNA samples were prepared from formalin-fixed, paraffin-embedded tissue sections using laser-capture microdissection. Loss of heterozygosity (LOH) assays for three microsatellite polymorphic markers on chromosome 9p21 (IFNA and D9S171), regions of putative tumor suppressor gene p16, and on chromosome 17p13 (TP53), the p53 tumor suppressor gene locus, were done. X-chromosome inactivation analysis was done on the urothelial tumors from 11 female patients. RESULTS: Seventeen of 21 (81%) cases showed allelic loss in one or more of the urothelial tumors in at least one of the three polymorphic markers analyzed. Concordant allelic loss patterns between each coexisting urothelial tumor were seen in only 3 of 21 (14%) cases. A concordant pattern of nonrandom X-chromosome inactivation in the multiple coexisting urothelial tumors was seen in only 3 of 11 female patients; of these 3 cases, only one displayed an identical allelic loss pattern in all of the tumors on LOH analysis. CONCLUSION: LOH and X-chromosome inactivation assays show that the coexisting tumors in many cases of multifocal urothelial carcinoma have a unique clonal origin and arise from independently transformed progenitor urothelial cells, supporting the "field effect" theory for urothelial carcinogenesis.

Adult↗

Application of molecular diagnostic techniques to renal epithelial neoplasms.

The application of molecular and cytogenetic techniques to the study of renal neoplasia has resulted in improved understanding of the biologic mechanisms that are responsible for tumor development and progression. It also revealed that several different and specific genetic events are responsible for tumorigenesis in the various categories and subcategories of renal tumors. The ultimate goal of research on the molecular pathology of renal neoplasms is a complete understanding of the genetics of these tumors, which will, in turn, aid in making the correct diagnosis, accurately assessing prognosis, and selecting appropriate and targeted therapeutic options.

Adenocarcinoma, Clear Cell↗

Thyroid transcription factor 1 expression in small cell carcinoma of the urinary bladder: an immunohistochemical profile of 44 cases.

Small cell carcinoma of the urinary bladder is a rare and aggressive tumor resembling small cell carcinoma of the lung. Thyroid transcription factor 1 (TTF-1) expression is common in small cell carcinomas arising in the lung. However, studies of its expression in extrapulmonary small cell carcinomas have yielded varying results. Because information concerning the immunohistochemical profile of small cell carcinoma of the urinary bladder is limited, we investigated the immunoreactivity of this tumor to a battery of antibodies in a series of 44 cases. Using 5-mum sections cut from paraffin-embedded tissue blocks, immunohistochemistry was performed to detect TTF-1, cytokeratin (CK) 7, CK20, and uroplakin antigenicity in 44 cases of small cell carcinoma of the urinary bladder. None of the patients had primary lung tumors. The TTF-1 immunohistochemical stain showed nuclear positivity in 17 cases (39%). Positive immunostaining for CK7 was observed in 26 cases (59%). There was no positive staining with either CK20 or uroplakin. There was no correlation between TTF-1 expression and survival (P = .27). In addition, TTF-1 expression did not correlate with clinicopathological characteristics, including age (P = .74), sex (P = .53), smoking history (P = .96), clinical stage (P = .10), pathological T stage (P = .50), lymph node metastasis (P = .40), and distant metastasis (P = .58). In summary, TTF-1 expression in small cell carcinoma of the urinary bladder was found in 39% of the tumors, demonstrating that this marker is expressed in small cell carcinomas other than those of pulmonary origin. Small cell carcinoma of the urinary bladder is positive for CK7 immunostaining in 59% of cases consistent with its origin from urothelium. Unlike urothelial carcinoma, expression of CK20 and uroplakin in small cell carcinoma of the urinary bladder is consistently negative, and thus, these stains do not appear to be useful in the diagnosis of this neoplasm. TTF-1 positivity is not a significant prognostic factor in small cell carcinoma of the urinary bladder.

Adult↗