Fluorescence in Situ Hybridization Identifies More Aggressive Types of Primarily Noninvasive (Stage pTa) Bladder Cancer

Exclusion of the uniform tetraploid cells significantly improves specificity of the urine FISH assay

The urine fluorescence in situ hybridization (FISH) assay (UroVysion™), with the current scoring criteria, has a higher sensitivity than routine cytopathology but a lower specificity. Among 215 urine FISH tests we performed, 45 had associated histopathology and clinical follow up. In this study, a cell with four signals for each probe was classified as a uniform tetraploid cell (UTC); a presumed reparative cell which is currently classified as an abnormal cell in the FDA approved assay. By using the existing criteria, the tests were scored as positive or negative before and after exclusion of the UTCs. Before the exclusion, 24 positive, 13 negative, seven false positive, and one false negative result were obtained with 96% sensitivity and 65% specificity. After the exclusion, the results changed to 22 positive, 19 negative, one false positive, and three false negatives resulting in a 88% sensitivity of 88% and a 95% specificity; a significant improvement in the specificity. We conclude that exclusion of the UTCs as abnormal cells would result in a more solid performance of the FISH assay.

Bladder cancer detection using FISH (UroVysion assay)

UroVysion is a fluorescence in situ hybridization assay that was developed for the detection of bladder cancer in urine specimens. It consists of fluorescently labeled DNA probes to the pericentromeric regions of chromosomes 3 (red), 7 (green), and 17 (aqua) and to the 9p21 band (gold) location of the P16 tumor suppressor gene. The UroVysion assay works by detecting urinary cells that have chromosomal abnormalities consistent with a diagnosis of bladder cancer. Studies have shown that UroVysion is more sensitive than urine cytology for the detection of all stages and grades of bladder cancer. UroVysion is Food and Drug Administration-approved for the detection of recurrent bladder cancer in voided urine specimens from patients with a history of bladder cancer and for the detection of bladder cancer in voided urine specimens from patients with gross or microscopic hematuria, but no previous history of bladder cancer. Recent studies also suggest that UroVysion may be useful for assessing superficial bladder cancer patients' response to bacillus Calmette-Guerin therapy and in detecting upper tract urothelial carcinoma.

Urine cytology and urine-based markers for bladder urothelial carcinoma detection and monitoring: developments and future prospects

Bladder cancer is currently diagnosed using cystoscopy and cytology in patients with suspicious signs and symptoms. These tests are also used to monitor patients with a history of bladder cancer. The recurrence rate for bladder cancer is high, thus necessitating long-term follow-up. Urine cytology has a high sensitivity and specificity for the detection of high-grade urothelial carcinoma, but lacks the sensitivity to detect low-grade tumors. Recently, multiple noninvasive urine-based bladder cancer tests have been developed. Many markers (BTA stat®, BTA TRAK®, ImmunoCyt™, NMP22® and UroVysion™) have already been approved by the US FDA for bladder cancer surveillance, while other markers are still undergoing development, preclinical and clinical investigation. An ideal bladder cancer test would be noninvasive, highly sensitive and specific, inexpensive, easy to perform and yield highly reproducible results. Many of the tests reviewed herein meet some, but not all, of these criteria.

Fluorescence in situ hybridization in diagnostic cytology

Fluorescence in situ hybridization (FISH) is a technique that uses fluorescently labeled DNA probes to detect chromosomal alterations in cells. FISH can detect various types of cytogenetic alterations including aneusomy (ie, abnormalities of chromosome copy number), duplication, amplification, deletion, and translocation. Because tumor cells generally contain chromosomal alterations, FISH is able to detect cells that have chromosomal abnormalities consistent with neoplasia in exfoliative and aspiration cytology specimens. This review will discuss the utility of FISH for the detection of bladder, lung, pancreatobiliary, and esophageal carcinoma in cytologic specimens.

Utility of a multiprobe fluorescence in situ hybridization assay in the detection of superficial urothelial bladder cancer

We evaluated the performance of a multiprobe FISH (fluorescence in situ hybridization) assay for noninvasive detection of superficial urothelial carcinoma (UC) in the bladder, in comparison to urinary cytology. Voided urine samples from 74 patients with superficial UC were analyzed by both techniques. Urine samples from 19 patients with muscle-invasive tumors and from 19 healthy control subjects were also studied. For FISH analysis, labeled probes for chromosomes 3, 7, 9, and 17 were used to assess chromosomal abnormalities indicative of malignancy. We found a significant difference between the overall sensitivity of FISH and cytology in superficial UC detection (70.3 versus 35.1%, respectively; P < 0.0001). This significant difference was maintained when superficial UCs were broken down into low grade (52.8 versus 13.9%, respectively; P < 0.0005) and high grade (86.8 versus 55.3%, respectively; P < 0.0015) tumors. Overall specificity was 100% for cytology and 94.7% for FISH (difference not significant). Of patients with suspicious cytology, 69% were positive by FISH. Together, these findings suggest that FISH assay for chromosomes 3, 7, 9, and 17 has a higher sensitivity than cytology and a similar specificity in the detection of superficial UC--which could be useful for reducing some cystoscopies in the accurate follow-up usually performed in these patients.

DNA–based molecular cytology for bladder cancer surveillance

Surveillance strategies for urothelial cancer (UC) recurrence have historically relied on the diagnostic combination of cystoscopy and conventional urinary cytology. In this review, results of studies evaluating the role of the fluorescence in situ hybridization (FISH) assay in bladder cancer surveillance are critically examined. The published research on FISH compared with conventional cytology and cystoscopy for bladder cancer was identified using a Medline search and was critically analyzed. Sensitivity and specificity data were tabulated and compared. FISH outperformed conventional cytology across all stages and grades in all published reports, and it detected malignancy before the development of lesions visible by cystoscopy. Although overall sensitivity was 48% for cytology and 74% for FISH, its greatest advantage was in the detection of high-grade UC, including carcinoma in situ (CIS). Cumulative data from comparative studies showed the sensitivity of cytology compared with FISH was 19% versus 58% for grade 1, 50% versus 77% for grade 2, and 71% versus 96% for grade 3. Similar findings occurred by stage, where cytology compared with FISH sensitivity was 35% versus 64% for Ta, 66% versus 83% for T1, and 76% versus 94% for muscle-invasive carcinoma. Notably, cytology detected only 67% of CIS versus 100% detection by FISH. Specificity data were comparable. Unlike conventional urinary cytology and cystoscopy, which depend on subjective visible microscopic or macroscopic changes, FISH allows identification of chromosomal abnormalities associated with malignant development before phenotypic expression of those alterations. Use of morphologic cellular changes allows more rapid detection of such alterations, combining the benefits of conventional cytology with molecular diagnostics. It is apparent that we are in the early phases of realizing the potential of molecular diagnostics.

Multitarget fluorescence in situ hybridization and melanoma antigen genes analysis in primary bladder carcinoma

Conventional urine cytology has a poor prognostic performance for detecting bladder cancer, particularly for low-grade tumors. Fluorescence in situ hybridization (FISH) for chromosomes altered in bladder cancer and testing for antigens selectively expressed in tumors are promising alternatives. This study investigated the use of FISH for detecting aneuploidy of chromosomes 3, 7, 17, and 9p21 and reverse transcriptase PCR (RT-PCR) for the expression of melanoma associated antigen (MAGE) genes for the diagnosis of bladder cancer in voided urine specimens. The two techniques were compared with cystoscopic bladder biopsy results in 47 patients with urothelial cancer and 15 patients with benign prostatic hyperplasia. FISH detected cancer in 42 of 47 patients (89.4%). This was significantly higher than the detection rate 30 of 47 patients (64.3%) by MAGE RT-PCR (P < 0.001). The sensitivity of FISH increased with histologic grade and stage of the tumors, correctly identifying 77.8% of pTa and pTis, 94.1% of pT1, and 100% of Pt2-4 tumors. MAGE, however, showed a decreased sensitivity in high grade advanced tumors; it was positive in 66.7% of pTa and pTis, 70.6% of pT1, and 50% of Pt2-4 tumors. Together, the tests correctly identified urothelial cancer in 46 of 47 patients (97.9%). Combined FISH and MAGE RT-PCR testing may offer a promising alternative to conventional urine cytology in screening high-risk populations and in monitoring bladder cancer patients for recurrent tumor.

Intermediate-risk urothelial carcinoma: an unresolved problem?

OBJECTIVES

To perform a biologic characterization of the urothelial neoplasms of patients in the intermediate-risk group using multicolor-fluorescence in situ hybridization (FISH). A general consensus has not been reached with regard to the optimal therapy and follow-up of patients with urothelial neoplasms at intermediate risk of progression. On the basis of the chromosomal pattern, we developed a new follow-up algorithm for this group and report our preliminary results.

METHODS

Voided urine samples of 51 consecutive patients (mean age 72.2 years, range 52 to 93) under follow-up after complete transurethral resection of intermediate-risk urothelial carcinoma were evaluated by liquid-based cytology (ThinPrep) and uCyt+. From the residual material, Multicolor-FISH (Urovysion) was performed. Any cystoscopically suspicious lesion was biopsied or removed transurethrally. The mean follow-up time was 14.2 months (range 6 to 30, SD 5.5).

RESULTS

Two of the 51 patients were not evaluated because of the presence of intense granulocytosis and insufficient urothelial cells. Of the 49 remaining patients, the results of the Multicolor-FISH analysis were negative (diploid chromosomal pattern) in 14; 20 patients showed the loss of one or both alleles of p16 and/or an aneuploidy of chromosome 3, and 15 patients had aneuploidy of chromosome 7 and/or 17. Of the 14 FISH-negative patients, 2 (14.3%) had histologically verified recurrence, and 3 (15.0%) of the 20 p16/3-positive patients had recurrence and 9 (60.0%) of the 15 7/17-positive patients had either recurrence or progression.

CONCLUSIONS

Using the Urovysion test, it is possible to predict the biologic behavior of urothelial cancer with a significant impact on the follow-up of patients. The intermediate-risk group of urothelial cancer can be eliminated in the routine workup by classifying these patients according to their chromosomal pattern and defining those patients who can follow the low-risk scheme and those who must be monitored according to the guidelines for high-risk superficial lesions.

DNA cytometric features in biopsies of TaT1 urothelial cell cancer predict recurrence and stage progression more accurately than stage, grade, or treatment modality

OBJECTIVES

To compare retrospectively the predictive value for recurrence and stage progression of DNA ploidy and S-phase fraction by flow cytometry and highly automated ultrafast image cytometry (ICM) in biopsies of TaT1 urothelial cell carcinomas (UCCs) of the urinary bladder with stage, grade, other pathologic features, and treatment.

METHODS

Three experienced pathologists reviewed the stage and grade of 228 UCCs; 193 (85%) consensus cases were analyzed further. We had enough material for single-cell suspensions for both flow cytometry and ICM in 183 cases (94.8%). The 2001 European Society for Analytical Cellular Pathology standards for DNA ICM were followed. The predictive value of DNA features, classic prognosticators (stage, grade, carcinoma in situ, multicentricity), and treatment modality for recurrence and stage progression were analyzed with univariate (Kaplan-Meier) survival and multivariate (Cox model) regression analysis. Ta and T1 cases were analyzed separately.

RESULTS

Of the 228 cases, 88 (51.5%) recurred and 13 (7.6%) progressed. On univariate analysis, most of the DNA features studied were statistically significant. Treatment modality and grade were only prognostic for progression (not for recurrence) and only in Ta cases. On multivariate analysis, DNA ICM features performed best; the strongest recurrence predictor for Ta UCC was a DNA index (DI) of 1.0 versus all others, and for T1 UCC, a DI of less than 1.3 versus 1.3 or greater. The best stage progression predictor for Ta UCCs was a DI of 1.0 plus an S-phase fraction of less than 10%, and for T1 UCCs, a DI of less than 1.3 versus 1.3 or greater. With multivariate analysis, sex, age, grade, carcinoma in situ, multicentricity, and treatment modality were excluded once the DNA ICM features were selected.

CONCLUSIONS

DNA image cytometric features predict recurrence and stage progression in TaT1 UCC biopsies more accurately than classic prognostic factors, independent of treatment modality.

Centrosome hyperamplification and chromosomal instability in bladder cancer

OBJECTIVE

Chromosomal instability (CIN) is a common feature of malignant tumors. Centrosome hyperamplification (CH) occurs frequently in human cancers, and may be a contributing factor in CIN. In this study, we investigated the relationship between CH and CIN in bladder cancer.

METHODS

Clinical samples obtained by transurethral resection from 22 patients with bladder cancer were examined (histological grade G1, 5 cases; G2, 6 cases; G3, 11 cases). CH was evaluated by immunohistochemistry using anti-pericentrin antibody. CIN was evaluated by fluorescence in situ hybridization (FISH). FISH probes for pericentromeric regions of chromosomes 3, 7, and 17 were hybridized to touch preparations of nuclei from frozen tissues. We also analyzed the centrosome replication cycle of bladder cancer by laser scanning cytometry (LSC).

RESULTS

Of the 22 cases examined, 18 (81.8%) had centrosome hyperamplification: CH 0, 4 cases (18.1%); CH I, 5 cases (22.7%); CH II, 5 cases (22.7%); CH III, 8 cases (36.4%). The grade of CH was directly proportional to the histological grade (p=0.03, chi(2) test). LSC analysis showed that the centrosome replication cycle was well regulated in pathologically low-grade bladder cancer, which did not have chromosomal instability. In contrast, we found marked variability of centrosomes in pathologically high-grade bladder cancer, which had chromosomal instability. CH and CIN were both detected in pathologically high-grade tumors. The grade of CH was directly proportional to the CIN grade (p=0.0079, chi(2) test).

CONCLUSION

The results of the present study suggest that CH may be involved in CIN in bladder cancer.

Genetic instability in superficial bladder cancer and adjacent mucosa: an interphase cytogenetic study

A systematic analysis of both tumors and the surrounding urothelium to help identify what lies behind the mechanism of multifocal tumor development has not yet been performed. In this study we investigated chromosome 1, 7, 9, and 17 aneusomy in 25 superficial papillary carcinomas and in 51 tissue samples taken from sites of macroscopically uninvolved urothelium surrounding the tumors, using the fluorescence in situ hybridization method. Our data demonstrated a close genetic relationship between all examined tumors and normal-appearing mucosa. Numeric aberrations of chromosomes 1, 7, 9, and 17 were found to exhibit similar patterns in all analyzed specimens, although with different frequencies.

Clinical evaluation of a multi-target fluorescent in situ hybridization assay for detection of bladder cancer

PURPOSE

The UroVysion fluorescence in situ hybridization assay (UroVysion Bladder Cancer Recurrence Kit, Vysis, Inc., Downers Grove, Illinois) is a multi-target assay that detects aneuploidy of chromosomes 3, 7 and 17, and loss of the 9p21 band in exfoliated cells in urine from patients with transitional cell carcinoma. We performed 2 multicenter trials. In 1 trial we compared the sensitivity of the FISH assay to the BTA Stat test (Bion Scientific, Redmond, Washington) and voided cytology in the detection of transitional cell carcinoma. In a separate study of healthy volunteers and patients with other (nontransitional cell carcinoma) conditions we determined the specificity of the FISH assay.

MATERIALS AND METHODS

A total of 176 patients with transitional cell carcinoma in the previous 9 months provided voided urine before cystoscopy. Each specimen was split, preserved and shipped to a central laboratory where all 3 tests were performed. All sites were blinded to results. Sensitivity calculations were based on central pathology review of resected tissue. Specificity was determined by testing 275 volunteers who were healthy and with nontransitional cell carcinoma conditions.

RESULTS

The 21 sites enrolled 176 patients with a history of transitional cell carcinoma, with 62 recurrences while undergoing surveillance. Overall sensitivities (with 95% CI) were FISH 71% (95% CI 58 to 82), BTA Stat test 50% (37 to 63) and cytology 26% (16 to 39). FISH was negative in 260 of the 275 healthy volunteers or patients with no history of transitional cell carcinoma (specificity 94.5%).

CONCLUSIONS

Sensitivity of the FISH assay is superior to that of cytology and at least equivalent to the BTA Stat test in detecting recurrent transitional cell carcinoma. Its specificity approaches that of cytology. Further testing of its clinical use is warranted.

Multiprobe FISH for enhanced detection of bladder cancer in voided urine specimens and bladder washings

The aim of this study was to evaluate the UroVysion (Vysis, Downers Grove, IL) fluorescence in situ hybridization (FISH) test for improved detection of bladder cancer in urinary specimens. Three groups of specimens were examined, including voided urine specimens (1) collected before resection of bladder cancer, (2) from cystoscopically negative bladders of patients with previous bladder cancer, and (3) from patients with benign prostatic hyperplasia (controls). FISH positivity was defined as more than 2 urothelial cells with an abnormal signal copy number of at least 1 of the 4 probes. FISH was positive in 1 of 27 control specimens and in 33 (73%) of 45 pTa, 12 (100%) of 12 pT1, and 13 (100%) of 13 pT2-4 tumors. The results were similar in a series of 68 bladder washings. In addition, FISH of voided urine specimens was positive in 5 of 10 patients with negative follow-up cystoscopy results. Subsequent recurrence was found in 4 of these patients but in none of 5 patients with FISH-negative results. Multiprobe FISH markedly improves the sensitivity and specificity of cytology for the detection of bladder cancer in urine specimens.

Noninvasive detection and prediction of bladder cancer by fluorescence in situ hybridization analysis of exfoliated urothelial cells in voided urine

OBJECTIVES

To investigate the clinical utility of fluorescence in situ hybridization (FISH) of voided urine in the detection of bladder cancer and the prediction of its recurrence.

METHODS

FISH with centromere-specific probes for chromosomes 9 and 17 was performed to evaluate the chromosomal alterations of exfoliated urothelial cells in voided urine obtained from 44 patients with bladder cancer and 20 controls. The analysis was also performed in 17 patients with bladder cancer after complete transurethral resection to prospectively determine whether FISH can predict tumor recurrence.

RESULTS

The sensitivity to detect bladder cancer by FISH analysis (85%) was significantly higher than that by urine cytologic examination (32%) and by the bladder tumor antigen test (64%) (P <0.0001 and P = 0.026, respectively). The specificity of FISH, cytologic analysis, and the bladder tumor antigen test was 95%, 100%, and 80%, respectively. Among the 17 patients tested after transurethral resection, 7 of 13 FISH-positive patients developed tumor recurrence within the 27-month follow-up period; none of 4 FISH-negative patients developed recurrence during the same period. The recurrence rate in patients with the loss of chromosome 17 was 100%, significantly higher than the 23% for patients without this alteration (P = 0.015).

CONCLUSIONS

These findings suggest that FISH analysis of exfoliated urothelial cells in voided urine can efficiently detect bladder cancer and predict its recurrence.

Interphase cytogenetics of bladder cancer progression: relationship between aneusomy, DNA ploidy pattern, histopathology, and clinical outcome

In the present study, different stages of transitional cell carcinoma of the bladder were analyzed by fluorescent in situ hybridization, using probes specific for pericentromeric classical satellite. Seventy primary tumors were evaluated for chromosomes 1, 7, 9, 17, and ploidy by flow cytometry. The results were correlated, after a mean follow-up period, with ploidy, histopathological characteristics, recurrence, and progression. Firstly, our data demonstrated that the sensitivity of fluorescence in situ hybridization in detecting quantitative DNA aberrations exceeds that of flow cytometry. The frequency of chromosome 1 and 9 aberrations was not significantly different in diploid and aneuploid tumors of different stage and grade. In contrast, the chromosome 7 and 17 aneusomy showed greater differences between pT1 and pT2-3 tumors (P<0.032 and P<0.0006, respectively) than between stage pTa and pT1. An increasing number of aberrations was observed in all chromosomes examined from tumors of patients that afterwards underwent cystectomy and/or had recurrent tumors. This study indicates that fluorescence in situ hybridization could be used to detect genetic changes relevant to patient outcome. These genetic changes could identify patients at high risk of recurrence and possible progression.

The development of a multitarget, multicolor fluorescence in situ hybridization assay for the detection of urothelial carcinoma in urine

The purpose of this study was to develop a multitarget, multicolor fluorescence in situ hybridization (FISH) assay for the detection of urothelial carcinoma (UC) in urine specimens. Urinary cells obtained from voided urine specimens of 21 patients with UC and 9 normal donors were analyzed with nine different centromere enumeration probes and a single locus-specific indicator probe to determine an optimal set of FISH probes for UC detection. The four probes with the greatest sensitivity for UC detection were then labeled with a unique fluorophore and combined into a single probe set. The probes with the greatest combined sensitivity for UC detection were CEP3, CEP7, CEP17, and the 9p21 (P16) LSI. This probe set was used to evaluate urine specimens acquired from 179 patients for prospective testing (46 with biopsy-proven UC). FISH slides were evaluated by scanning the slide for cells with nuclear features suggestive of malignancy and assessing the FISH signal pattern of these cells for polysomy (ie, gains of two or more different chromosomes). A receiver operator characteristic curve revealed that a cutoff of 5 cells with polysomy as the positive criterion for cancer resulted in an overall sensitivity of 84.2% for patients with biopsy-proven UC and a specificity of 91.8% among patients with genitourinary disorders but no evidence of UC. This study demonstrates that a multitarget, multicolor FISH assay containing centromeric probes to chromosomes 3, 7, and 17 and a locus-specific probe to band 9p21 has high sensitivity and specificity for the detection of UC in voided urine specimens.

DNA ploidy and p53 protein expression in superficial transitional cell carcinoma of the bladder

Superficial transitional cell carcinoma of the bladder (STCCB) is a heterogeneous group of neoplasias with an unpredictable clinical course. In recent years many techniques have been used in order to predict the behaviour of these tumours at individual patient level. The aim of this study was to investigate in imprints from tumour biopsies the DNA ploidy and p53 protein expression in a group of 80 STCCB (pTa-pT1) patients in relation to histological grade and recurrence status. The DNA content was studied in Feulgen-stained imprints by the image analysis technique using a SAMBA 2005 analyser. In order to investigate p53 protein expression an avidin-extravidin immunocytochemical technique was used. According to our measurements a strong correlation was observed between recurrence status and DNA ploidy status (P < 0.001). No statistical difference was found in DNA ploidy status and grade of malignancy (P = 0.68). A statistically significant difference was found in p53 protein expression between recurrent and nonrecurrent tumours (P < 0.001). No statistically significant difference was found among tumours of grade I, grade II and grade III (P = 0.42). These results could provide useful information on the potential behaviour of STCCB.

Mutation of cell cycle regulators and their impact on superficial bladder cancer

Early cytogenetic studies in bladder cancer identify regions of chromosomal gain or loss that can be candidate loci for oncogenes and tumor suppressor genes. Oncogenes with potential prognostic significance identified in bladder cancer the RAS family, epidermal growth factor receptor, ERBB-2, MDM2, and cyclin D1. The TP53 gene has been the most thoroughly characterized tumor suppressor gene in bladder cancer, with correlation of TP53 alterations with type of carcinogenic exposure, tumor stage and grade, as well as prognosis. Studies evaluating alterations of the retinoblastoma pathway have identified the retinoblastoma gene, RB, p161NK4A/CDKN2, and E2F-1 as tumor suppressor genes with potential prognostic significance in patients with bladder cancer. Better understanding of the genetic mechanisms underlying bladder tumor development and progression will allow better prevention, diagnosis, and treatment strategies.

Aneusomy of chromosomes 7 and 17 predicts the recurrence of transitional cell carcinoma of the urinary bladder

OBJECTIVE

To determine if changes in chromosome 7 and 17 copy number can be used to predict recurrence in patients with primary noninvasive (pTa) or superficially invasive (pT1) transitional cell carcinoma (TCC) of the urinary bladder.

PATIENTS AND METHODS

Tissue specimens for 129 tumours from 52 patients (38 men and 14 women) with pTa/pT1 TCC at first diagnosis were retrieved from pathology archives. All patient notes were accessed and disease outcome documented for superficial (pTa/pT1) recurrence or progression to detrusor muscle invasion (>/= pT2). The tumours were examined for chromosomal copy number of chromosomes 7 and 17 using fluorescence in situ hybridization (FISH) with chromosome-specific probes. The copy number of chromosomes 7 and 17 was determined in interphase nuclei on intact 6 microm tissue sections.

RESULTS

Aneusomy of chromosomes 7 and 17 was detected in the index primary tumours of 10 of 32 (31%) patients with subsequent recurrent disease. No aneusomy for these chromosomes was detected in primary tumours from 20 patients with no detect-able recurrence (P = 0.0082). The relative risk of recurrence was 3.62 times greater (95% confidence interval 1.6-8.1, Cox's multiple regression P = 0.0019) for patients with chromosomal aneusomy in primary TCC. Neither stage nor grade of the primary tumours was associated with recurrence in these patients, nor was there a significant association with increased grade (G2/3) or stage (>/= pT2) at recurrence.

CONCLUSION

These results suggest that the measurement of aneusomy by FISH, using markers for chromosomes 7 and 17, predict recurrence in a subgroup of patients with pTa/pT1 tumours at presentation. This finding may offer a new objective and quantitative test for patients destined to recur.

Fluorescence in situ hybridization in cervical smears: detection of numerical aberrations of chromosomes 7, 3, and X and relationship to HPV infection

BACKGROUND

Human papillomavirus (HPV) is known to play a pivotal role in cervical carcinogenesis. Chromosomal aberrations are known to be related to different biological behaviors of malignant lesions. We analyzed whether numerical chromosomal aberrations, related to more aggressive tumor types, are found not only in high-grade squamous intraepithelial lesions (HSIL) but also in low-grade SIL (LSIL) of the cervix and evaluated their relationship to HPV infection.

METHODS

Eighty women (19 to 74 years of age) were included in this study and grouped according to the Bethesda System: within normal limits (WNL), LSIL, and HSIL. By FISH, chromosomes 7 and X, and in part chromosome 3, were analyzed for numerical aberrations. Using the hybrid capture system HPV detection was performed.

RESULTS

All 20 patients with cervical smear WNL had regular diploid chromosomal pattern and were negative for HPV. Thirteen of the 29 (41.2%) patients with LSIL showed trisomy 7, in association with trisomy X in 4 cases (12.9%). Single trisomy X was detected in 4 cases (12.9%). In 3 of 15 (20%) cases analyzed for chromosome 3 trisomy was observed. Trisomy 3 was associated with trisomy 7 and X or with trisomy 7 alone. The hybrid capture test was performed in 16 patients of this group. Two patients were positive for HPV probe A, 9 for probe B, and 2 for A and B, and 3 patients were negative. Twenty-three of the 29 patients (79.3%) with HSIL showed trisomy 7. Twelve of the 29 patients (41.3%) had an additional trisomy X. Single trisomy X was seen in only 2 cases (6. 9%). Twenty-two patients with HSIL were tested also for chromosome 3. Nine of the 22 patients (40.9%) showed trisomy 3, associated with trisomy 7 or with trisomy 7 and X. In 25 of the 29 patients HPV detection by the hybrid capture system was performed. HPV probe B was positive in 15 cases (60%). One patient was positive for both probes, A and B. Nine (36%) of the patients with HSIL were negative for both HPV probes. No positivity was observed for HPV probe A alone.

CONCLUSION

Our data confirm the pivotal role of HPV in cervical carcinogenesis as it seems to cause changes in the chromosomal pattern of premalignant lesions. Additionally, trisomy 7 may be considered an early event in cervical carcinogenesis, persisting and increasing with progression of the lesion. The roles of trisomy 3 and X need further evaluation.

Arylamine N-acetyltransferase type 2 (NAT2), chromosome 8 aneuploidy, and identification of a novel NAT1 cosmid clone: an investigation in bladder cancer by interphase FISH

Two genes (arylamine N-acetyltransferase types 1 and 2, NAT1 and NAT2), which are known to metabolize bladder carcinogens, are located on chromosome band 8p22. Alterations in chromosome 8, including deletions of 8p, occur frequently in many epithelium-derived tumors. In this study, fluorescence in situ hybridization (FISH) was used for study of the relationship between chromosome 8 deletions in the region of NAT1 and NAT2 and grade and stage of tumor in bladder cancer. Cells from 52 bladder tumors were examined by dual-labeling FISH with a centromere 8-specific probe and a cosmid probe for NAT2. A more limited number were examined for loss with both the NAT2 probe and a newly constructed NAT1-specific cosmid. Loss of NAT2 was found in 6/52 patients in more than 30% of cells, and in 10/52 in 10%-30% of cells examined. Six samples also showed loss of NAT1, indicating that the region of deletion spans at least the distance of the two genes. No obvious correlation between loss of NAT genes with grade and stage of tumor was evident. Interestingly, 17/52 (32%) tumors showed an increased copy number of chromosome 8, with tumors of low stage showing relatively smaller increases of chromosome 8. Loss of 8p22 and genetic instability involving chromosome 8 indicate that this chromosome is important in bladder cancer and that NAT genes will act as important genetic landmarks in defining deletions in this disease. Genes Chromosomes Cancer 25:376-383, 1999.

Numerical chromosomal aberrations in muscle invasive squamous cell and transitional cell cancer of the urinary bladder: an alternative to classic prognostic indicators?

OBJECTIVES

To evaluate the prognostic value of chromosomal aberrations in muscle invasive bladder cancer, because they are of diagnostic and prognostic significance in superficial bladder cancer.

METHODS

One hundred ninety patients, who underwent radical cystectomy because of squamous cell carcinoma (SCC) of the urinary bladder in 94 cases and transitional cell carcinoma (TCC) in 96 cases, were studied retrospectively. Numerical aberrations of chromosomes 7, 9, and 17, p53 positivity, histologic stage and grade, histologic tumor type, lymph node status, and the presence of bilharzial eggs were investigated as possible prognostic factors.

RESULTS

Univariate analysis demonstrated the prognostic significance of all parameters analyzed, excluding chromosome 9. Multivariate analysis revealed only T category (P = 0.01095266), lymph node involvement (P = 0.00054877), and p53 positivity (P = 0.0316974) to be independent prognostic factors in muscle invasive SCC and TCC.

CONCLUSIONS

Although chromosomal aberrations are associated with progression-free survival, they are not independent prognostic factors and give the clinician no additional information on patients with muscle invasive bladder cancer.

Multifocality of transitional cell carcinoma results from genetic instability of entire transitional epithelium

OBJECTIVES

Multifocality of transitional cell carcinoma (TCC) has been attributed to seeding of exfoliated tumor cells or to a general sensitivity of the entire urothelium to carcinogenic stimuli. By contrast, TCC has been shown to evolve as a consequence of genetic defects and chromosomal instability. We analyzed chromosomal patterns, total DNA content, and p53 and Ki67 expression in malignant and normal transitional cells to evaluate their relationship to the development of multifocal TCC.

METHODS

Included in the study were 47 patients, 16 women and 31 men, with a mean age of 70.04 years (range 37 to 83). Of 47 patients, 45 had TCC of the urinary bladder and 7 of those had synchronous ureteral involvement. Two patients had ureteral TCC and a history of TCC of the bladder. Using fluorescence in situ hybridization, numerical aberrations of chromosomes 7, 9, and 17 were detected in imprint specimens of histologically verified tumor and "normal" urothelium and were compared with static ploidy and p53 and Ki67 expression.

RESULTS

Chromosome 7 was altered in 93.6%, chromosome 9 in 63.8% (including monosomy), and chromosome 17 in 87.2% of the 47 analyzed tumor and normal imprints. Differences between tumor and normal epithelium were observed in aberrational frequencies (number of cells showing chromosomal aberrations calculated on 200 cells counted, given in percentages). DNA content was aneuploid in all tumor specimens, but diploid in 20 (42.5%) of 47 normal specimens, according to lower aberration frequencies in these patients. p53 detection was positive in 82.9% of the tumor specimens and 76.6% of the normal specimens. Ki67 was positive in 87.2% of the tumor imprints and in 72.3% of the normal specimens.

CONCLUSIONS

These data suggest a general genetic instability as a reason for multifocality in the entire transitional epithelium.

Nephrogenic adenoma in renal transplant recipients: a truly benign lesion?

OBJECTIVES

Nephrogenic adenoma is a benign metaplastic lesion of the urinary bladder, reported to occur as a response to inflammation, trauma, intravesical therapies, and after renal transplantation. The aim of this study was to evaluate on the basis of chromosomal analysis whether nephrogenic adenoma really is benign.

METHODS

Twelve renal transplant recipients with histologically verified nephrogenic adenoma were analyzed for numerical aberrations of chromosomes 7, 9, and 17. Results were related to total DNA content, p53 and Ki-67 positivity, and clinical outcome. Ten patients with superficial bladder cancer and 10 healthy renal transplant recipients formed the control groups.

RESULTS

All 12 patients with nephrogenic adenoma had monosomy 9 in a mean of 24.3% (range 20% to 30%) of the evaluated cells; 3 patients had an additional trisomy 7 in a mean of 8% (range 6% to 10%) of the counted cells. Chromosome 1 7 was disomic in all patients. DNA histograms were diploid in 11 of the 12 patients and aneuploid in 1 patient. No p53 and Ki-67 positivity was present in this group. All patients with superficial bladder cancer had monosomy 9 in a mean of 79.8% (range 75% to 85%) of the counted cells. Two patients were found to have an additional trisomy 7 in 50% and 65% of the cells, respectively. The latter had an aneuploid histogram; the others had haploid/diploid histograms. p53 was negative in all specimens. Ki-67 positivity was present in 70% of these patients. All healthy transplant recipients had disomic chromosomal patterns according to diploid DNA histograms and negative immunocytochemical results.

CONCLUSIONS

Even if in a lower percentage of cells, aberrations of chromosome 7 and 9 were detected in nephrogenic adenoma. It therefore cannot be excluded that nephrogenic adenomas in immunosuppressed renal transplant recipients may develop into malignant lesions.

Bladder tumor markers: need, nature and application. 1. Nucleus-based markers

Urothelial tumors are common: their diagnosis and long-term management represent a large part of most urologists' workload. The majority of such tumors are 'superficial' and are mostly managed by repeated cystoscopic surveillance and treatment. A smaller but significant group of patients either start with, or subsequently progress to, more invasive disease, thus requiring an alternative and more invasive treatment. Maximizing the benefit/risk ratio of the diagnosis and the various treatment options of bladder tumors requires the availability of a reliable tumor marker. The concept of tumor markers encompasses the utilization of any detectable deviation from normality that is indicative of neoplasia. For bladder cancer, most of these markers are present in urine. In this part of the review we examine, from the clinician's point of view, the literature verdict on older techniques such as cytology and cytometry, as well as the current status of new nucleus-based tests such as P53, telomerase, NMP22 and Ki67.

Numerical aberrations of chromosomes 7, 9 and 17 in squamous cell and transitional cell cancer of the bladder: a comparative study performed by fluorescence in situ hybridization

PURPOSE

Since squamous cell differs from transitional cell cancer regarding histopathology, clinical outcome and etiology, the underlying genetic effects of these 2 tumor types may also be different. We compared numerical aberrations of chromosomes 7, 9 and 17 in bilharzial squamous cell carcinoma, and bilharzial and nonbilharzial transitional cell carcinoma by fluorescence in situ hybridization, and correlated the findings to p53 positivity of the 3 tumor types.

MATERIALS AND METHODS

Cystectomy for invasive bladder cancer was performed in 169 men and 51 women with a mean age of 54.8 years (range 28 to 83). Of the 220 patients 100 (45.4%) had histologically verified bilharzial squamous cell carcinoma, 61 (27.7%) bilharzial transitional cell carcinoma and 59 (26.8%) nonbilharzial transitional cell carcinoma. Using fluorescence in situ hybridization cystectomy specimens were evaluated for numerical aberrations of chromosomes 7, 9 and 17, and p53 detection was performed by immunohistochemistry.

RESULTS

Aberrations of chromosome 7 were observed in 79% of the bilharzial squamous cell carcinoma specimens, and 100% and 93.2% of bilharzial and nonbilharzial transitional cell carcinoma specimens, respectively (p = 0.00011). Aberrations of chromosome 9 were seen in 92% of squamous cell carcinoma specimens but in only 52.4% and 60.9% of bilharzial and nonbilharzial transitional cell carcinoma, respectively (p < 0.00001). Aberrations of chromosome 17 were found in only 29% of squamous cell carcinoma specimens, compared to 83.6% and 84.7% aberrations of chromosome 17 in both transitional cell carcinoma groups, respectively (p < 0.00001). The p53 over expression was similar in all 3 tumor types with 82% for squamous cell carcinoma, and 73.7% for bilharzial and 81.3% for nonbilharzial transitional cell carcinoma (not significant, p = 0.5285).

CONCLUSIONS

Our data show clear differences between chromosomal patterns of invasive bilharzial squamous cell carcinoma and invasive bilharzial or nonbilharzial transitional cell carcinoma but similar frequencies of p53 over expression in all 3 tumor types. However, aberrations of chromosome 9 were observed in all analyzed groups, which confirms the 2 pathways in the oncogenesis of squamous cell and transitional cell carcinoma at the cytogenetic level as suggested by molecular studies.

Numerical aberrations of chromosomes 7, 9 and 17 in squamous cell and transitional cell cancer of the bladder: a comparative study performed by fluorescence in situ hybridization

PURPOSE

Since squamous cell differs from transitional cell cancer regarding histopathology, clinical outcome and etiology, the underlying genetic effects of these 2 tumor types may also be different. We compared numerical aberrations of chromosomes 7, 9 and 17 in bilharzial squamous cell carcinoma, and bilharzial and nonbilharzial transitional cell carcinoma by fluorescence in situ hybridization, and correlated the findings to p53 positivity of the 3 tumor types.

MATERIALS AND METHODS

Cystectomy for invasive bladder cancer was performed in 169 men and 51 women with a mean age of 54.8 years (range 28 to 83). Of the 220 patients 100 (45.4%) had histologically verified bilharzial squamous cell carcinoma, 61 (27.7%) bilharzial transitional cell carcinoma and 59 (26.8%) nonbilharzial transitional cell carcinoma. Using fluorescence in situ hybridization cystectomy specimens were evaluated for numerical aberrations of chromosomes 7, 9 and 17, and p53 detection was performed by immunohistochemistry.

RESULTS

Aberrations of chromosome 7 were observed in 79% of the bilharzial squamous cell carcinoma specimens, and 100% and 93.2% of bilharzial and nonbilharzial transitional cell carcinoma specimens, respectively (p = 0.00011). Aberrations of chromosome 9 were seen in 92% of squamous cell carcinoma specimens but in only 52.4% and 60.9% of bilharzial and nonbilharzial transitional cell carcinoma, respectively (p < 0.00001). Aberrations of chromosome 17 were found in only 29% of squamous cell carcinoma specimens, compared to 83.6% and 84.7% aberrations of chromosome 17 in both transitional cell carcinoma groups, respectively (p < 0.00001). The p53 over expression was similar in all 3 tumor types with 82% for squamous cell carcinoma, and 73.7% for bilharzial and 81.3% for nonbilharzial transitional cell carcinoma (not significant, p = 0.5285).

CONCLUSIONS

Our data show clear differences between chromosomal patterns of invasive bilharzial squamous cell carcinoma and invasive bilharzial or nonbilharzial transitional cell carcinoma but similar frequencies of p53 over expression in all 3 tumor types. However, aberrations of chromosome 9 were observed in all analyzed groups, which confirms the 2 pathways in the oncogenesis of squamous cell and transitional cell carcinoma at the cytogenetic level as suggested by molecular studies.

Does topical instillation therapy influence chromosomal aberrations in superficial bladder cancer?

PURPOSE

Patients with a high risk for superficial bladder cancer are treated by topical immuno-or chemotherapy after transurethral resection to reduce the chance of recurrence and/or progression. The aim of this study was to analyse if cytogenetical abnormalities, which are known to be constantly related to bladder cancer, are modified or eliminated by topical immuno- or chemotherapy.

MATERIALS AND METHODS

Using fluorescence in situ hybridization (FISH), the influence of topical instillation therapy with Bacillus Calmette-Gúerin (BCG) and Mitomycin C (MMC) on numerical aberrations of chromosomes 7, 9 and 17 was investigated in 25 patients with transitional cell cancer (TCC) of the bladder. Data were compared with histological and clinical outcome. Fifteen TCC patients with similar histological criteria without instillation therapy served as controls. Median follow-up was 30 +/- 2 months.

RESULTS

After BCG treatment 10 of 15 patients (66.6%) developed recurrent and 2/15 (13.3%) progressive disease. Three of 15 patients (20.0%) had no evidence of disease. Numerical aberrations did not change in 8 of the 15 BCG patients (53.3%) and changed to a more aggressive pattern in 40.0% (6/15). Five of 10 MMC treated patients (50.0%) developed a recurrent tumor, 2/10 (20.0%) progressed and 3/10 (30.0%) had no evidence of disease. Four of 10 (40.0%) of these patients showed stable and 5/10 (50.0%) progressive chromosomal patterns. Only one patient in each group with primary chromosomal alterations changed to a regular diploid chromosomal pattern after therapy according to a complete clinical remission.

CONCLUSION

Even though topical immuno- and chemotherapy may be useful to delay recurrence and progression, chromosomal patterns remain basically unstable.