High Incidence and Early Onset of Urinary Tract Cancers in Patients with BK Polyomavirus Associated Nephropathy.

Over-immunosuppressed kidney transplant recipients are susceptible to malignancies and BK polyomavirus (BKPyV)-associated nephropathy (BKPyVAN). This study aimed to verify the association between BKPyV infection and urinary tract cancers (UTC). A total of 244 kidney transplant recipients were enrolled at Chang Gung Memorial Hospital from June 2000 to February 2020. Biopsy-proven BKPyVAN patients (n = 17) had worse kidney function (eGFR: 26 ± 13.7 vs. 47.8 ± 31.0 mL/min/1.73 m2). The 5-year allograft survival rates for patients with and without BKPyVAN were 67% and 93%, respectively (p = 0.0002), while the 10-year patient survival was not different between the two groups. BKPyVAN patients had a significantly higher incidence of UTC compared to the non-BKPyVAN group (29.4% vs. 6.6%). Kaplan-Meier analysis showed that the UTC-free survival rate was significantly lower in BKPyVAN patients, and the onset of UTC was significantly shorter in BKPyVAN patients (53.4 vs. 108.9 months). The multivariate logistic regression analysis demonstrated that age (RR = 1.062) and BKVAN (RR = 6.459) were the most significant risk factors for the development of UTC. Our study demonstrates that BKPyVAN patients have greater allograft losses, higher incidence, a lower cancer-free survival rate, and an earlier onset with a higher relative risk of developing UTC compared to non-BKPyVAN patients.

Can Epstein-Barr virus play a role in upper urinary tract urothelial carcinomas?

INTRODUCTION: Upper urinary tract urothelial carcinomas are very rare tumours with different biological behaviours. The Epstein-Barr virus, which is the first known oncogenic virus, is being investigated for various malignant tumours. It is known that this virus is associated with nasopharyngeal carcinoma, as well as multiple haematological malignancies, head and neck and gastric cancers. We aimed to determine the presence of the Epstein-Barr virus in upper urinary tract urothelial carcinomas using chromogenic in situ hybridisation (CISH). MATERIALS AND METHODS: A total of 44 upper urinary tract urothelial carcinomas from two different centres were included. Demographic data and survival rates were obtained from hospital records. One demonstrative paraffin block from each case was stained using Epstein-Barr encoded RNA (EBER) with an automated CISH procedure. The positivity of EBER was statistically analysed for prognostic factors. RESULTS: Among all patients, 38 were male and 6 were female. The mean age of the patients was 65.93 years. At the time of the study, 15 patients had died and 29 were alive. EBER-CISH positivity was found in 13 patients. Four showed strong EBER-CISH expression and nine showed weak expression. EBER-CISH positivity was not statistically related to any of the prognostic factors or to overall survival. DISCUSSION: Although EBER-CISH positivity showed no significant relation with prognostic factors, it was observed in one-third of all cases. Therefore, we think that the Epstein-Barr virus may have a role in the pathogenesis of upper urinary tract urothelial carcinomas. This finding needs to be supported by larger studies.

Unusual BK polyomavirus-associated urologic malignancies in renal transplant recipients: Report of two cases and review of the literature.

Renal transplant recipients are at increased risk of developing urologic malignancies, some of which are associated with prolonged BK virus infection. We report two cases of BK virus-associated carcinoma with variant morphological patterns (clear cell adenocarcinoma of the bladder and micropapillary urothelial carcinoma of the pelvicaliceal system) arising in the urinary tract of renal transplant recipients. In both cases, the diagnosis was initially established on cytologic specimens: on urine cytology in one patient and on fine needle aspiration of an inguinal lymph node in the other patient. The unusual cytologic features of both cases (multiple morphologies in one patient and micropapillary pattern in the other), co-occurrence of decoy cells in the urine of one patient and the occurrence of these tumors in renal transplant recipients raised the possibility of BK polyomavirus-associated malignancy and led to confirmatory SV40 immunostains that were positive. These cases expand the morphologic variants of BK virus-associated urologic malignancies diagnosed in solid organ transplant patients. While differentiating BK virus-infected cells from malignant cells in urine cytology specimens is a diagnostic challenge, greater awareness of their possible co-existence is vital, as this could be the only chance for an early diagnosis.

Treatment for presumed BK polyomavirus nephropathy and risk of urinary tract cancers among kidney transplant recipients in the United States.

Recent case series describe detection of BK polyomavirus (BKV) in urinary tract cancers in kidney transplant recipients, suggesting that BKV could contribute to the development of these cancers. We assessed risk for urinary tract cancers in kidney recipients with or without treatment for presumed BKV nephropathy (tBKVN) using data from the United States Transplant Cancer Match Study (2003-2013). Among 55 697 included recipients, 2015 (3.6%) were reported with tBKVN. Relative to the general population, incidence was similarly elevated (approximately 4.5-fold) for kidney cancer in recipients with or without tBKVN, and incidence was not increased in either group for prostate cancer. In contrast, for invasive bladder cancer, incidence was more strongly elevated in recipients with versus without tBKVN (standardized incidence ratios 4.5 vs. 1.7; N = 48 cases), corresponding to an incidence rate ratio (IRR) of 2.9 (95% confidence interval [CI] 1.0-8.2), adjusted for sex, age, transplant year, and use of polyclonal antibody induction. As a result, recipients with tBKVN had borderline increased incidence for all urothelial cancers combined (renal pelvis, ureter, and bladder cancers: adjusted IRR 2.2, 95% CI 0.9-5.4; N = 89 cases). Together with reports describing BKV detection in tumor tissues, these results support an association between BKV and urothelial carcinogenesis among kidney transplant recipients.

Human Polyomavirus Is Associated With Earlier Onset of Upper Urinary Tract Urothelial Carcinoma in Patients After Kidney Transplantation.

OBJECTIVES: Polyomavirus has been reported to be oncogenic due to viral integration into the human genome. A relatively high prevalence of upper urinary tract urothelial carcinoma (UTUC) was noted after kidney transplantation (KT) in Taiwan. However, little was known about the impact of polyomavirus on the urothelial cancer behavior. Therefore, the aim of this study is to analyze the characteristics of polyomavirus-related UTUC after KT. METHODS: From 2005 to 2014, 27 patients were found to have UTUCs after KT. All the patients underwent standard nephroureterectomy. Detailed perioperative parameters were obtained from chart records. A qualified pathologist who is blinded to the clinical outcome examined large T antigen expression and pathological features. All the patients were divided into two groups according to positive or negative expression of large T antigen. RESULTS: In the patient demography, a significantly younger median age was found in patients with large T antigen-positive UTUCs compared with the negative control group (48.1 ± 8.3 years versus 54.6 ± 4.1 years, respectively, P = .013). As for the pathological features and oncologic outcome, there were no obvious differences between these two groups. Non-organ-confined status and positive lymphovascular invasion are prognostic factors associated with systemic disease recurrence (P = .017 and .001, respectively). CONCLUSIONS: Although UTUC commonly develops in the elderly, earlier onset of post-KT UTUCs was observed especially in patients with positive large T antigen expression in our cohort. This preliminary result provides valuable experience suggesting more frequent upper urinary tract screening for polyomavirus infected patients after KT in Taiwan.

Should the BK polyomavirus cytopathic effect be best classified as atypical or benign in urine cytology specimens?

BACKGROUND: According to The Paris System for Reporting Urinary Cytology (TPS), the category of atypical urothelial cells (AUC) should not be applied to specimens in which cellular changes can be entirely attributed to the polyoma (BK) virus cytopathic effect (CPE). Until recently, cases with BK CPE at The Johns Hopkins Hospital were categorized as atypical urothelial cells of uncertain significance (AUC-US), which is equivalent to the TPS AUC category. This study was performed to determine how significantly the rate of AUC-US specimens would decrease if specimens with only BK CPE were classified as benign. METHODS: Two reviewers and 1 adjudicator re-evaluated urinary tract specimens to determine whether sufficient cytological atypia justified an AUC-US diagnosis independent of the presence of BK CPE. For patients with surgical follow-up, the rate of high-grade urothelial carcinoma (HGUC) on tissue biopsy was tracked over a 5-year period. RESULTS: The reclassification rate of AUC-US cases with BK CPE as benign was 62.6%. The rate of subsequent HGUC was 6.0% for cases reclassified as benign and 10.0% for cases still classified as AUC-US. These rates were not significantly elevated in comparison with control cohorts among all-comers. However, for patients without a history of HGUC, the rate of HGUC on follow-up was significantly elevated in comparison with the rate for a benign control cohort and was similar to the rate for the AUC-US control cohort. CONCLUSIONS: Reclassification as benign would have decreased the rate of AUC-US from 24.8% to 20.7% during the study year. However, the high rate of subsequent HGUC among nonsurveillance patients suggests that the reclassification of specimens with BK CPE in these patients may be inappropriate. Cancer Cytopathol 2016;124:436-42. © 2016 American Cancer Society.

The role of human papilloma virus in urological malignancies.

Human papillomavirus (HPV) is associated with cancer of the cervix uteri, penis, vulva, vagina, anus and oropharynx. However, the role of HPV infection in urological tumors is not yet clarified. HPV appears not to play a major causative role in renal and testicular carcinogenesis. However, HPV infection should be kept in mind regarding cases of prostate cancer, as well as in a sub-group of patients with bladder cancer with squamous differentiation. Concerning the role of HPV in penile cancer incidence, it is a recognized risk factor proven in a large number of studies. This short review provides an update regarding recent literature on HPV in urological malignancies, thereby, also discussing possible limitations on HPV detection in urological cancer.

Human papillomavirus burden in different cancers in Iran: a systematic assessment.

Certain types of human papillomaviruses (HPVs) are undoubtedly involved in genesis of human malignancies. HPV plays an etiological role in cervical cancer, but also in many vaginal, vulvar, anal and penile cancers, as well as head and neck cancers. In addition, a number of non-malignant diseases such as genital warts and recurrent respiratory papillomatosis are attributable to HPV. Moreover, HPV forms have detected in several other cancers including esophageal squamous cell carcinoma, lung, prostate, ovarian, breast, skin, colorectal and urinary tract cancers, but associations with etiology in these cases is controversial. The aim of this systematic assessment was to estimate the prevalence of HPV infection and HPV types in HPV-associated cancers, HPV-related non-malignant diseases and in cancers that may be associated with HPV in Iran. The present investigation covered 61 studies on a variety of cancers in Iranian populations. HPV prevalence was 77.5 % and 32.4% in cervical cancer and head and neck cancers, respectively. HPV was detected in 23.1%, 22.2%, 10.4%, 30.9%, 14% and 25.2% of esophageal squamous cell, lung, prostate, urinary tract cancers, breast and skin cancers, respectively. HPV16 and 18 were the most frequent HPV types in all cancers. The findings of present study imply that current HPV vaccines for cervical cancer may decrease the burden of other cancers if they are really related to HPV.

Outcomes of kidney transplant tourism and risk factors for de novo urothelial carcinoma.

BACKGROUND: To date, the outcomes of transplant tourism have not been reported extensively. In addition, data about the accuracy of urine cytology for the detection and the role of the BK virus (BKV) in the carcinogenesis of urothelial carcinoma (UC) after renal transplantation are lacking. METHODS: Three hundred seven patients who received deceased donor kidney transplants between January 2003 and December 2009 were retrospectively studied. The clinical parameters and outcomes between the domestic and tourist groups were compared. We also investigated the risk factors and role of BKV in the carcinogenesis of de novo UC by quantitative real-time polymerase chain reaction. RESULTS: The subjects in the tourist group were older at transplantation and had a shorter dialysis time before transplantation. There were significantly higher incidence rates of BKV viruria, Pneumocystis jiroveci pneumonia, and malignancy in the tourist group. Graft and patient survival were superior in the domestic group. A total of 43 cancers were identified, and the most common type of malignancy was UC (23 patients, 53.5%). The tourist group had a significantly higher incidence of tumors. The sensitivity and specificity of urine cytology for detecting UC were 73.9% and 94.7%, respectively. Independent predictors of UC included female sex, use of Chinese herbal medicine, and transplant tourism. Only two patients (8.7%) with UC had detectable BKV. CONCLUSIONS: Transplant tourism was a risk factor for infection and de novo malignancy. Urothelial carcinoma was the most common malignancy after kidney transplantation. Regular screening for the early detection of UC by urine cytology or periodic sonographic surveys is mandatory, especially for those at high risk.

HERV-E-mediated modulation of PLA2G4A transcription in urothelial carcinoma.

Human endogenous retroviruses (HERV) and related elements account for more than 8% of the human genome and significantly contribute to the human transcriptome by long terminal repeat (LTR) promoter activity. In this context, HERVs are thought to intervene in the expression of adjacent genes by providing regulatory sequences (cis-effect) or via noncoding RNA including natural antisense transcripts. To address the potential impact of HERV activity in urothelial carcinoma, we comparatively analyzed the HERV transcription profiles in paired samples of non-malignant urothelium and urothelial carcinoma derived from 13 patients with bladder cancer by means of a retrovirus-specific microarray (RetroArray). We established a characteristic HERV signature consisting of six ubiquitously active HERV subgroups (E4-1, HERV-Rb, ERV9, HERV-K-T47D, NMWV3, HERV-KC4). The transcription pattern is largely identical in human urothelial carcinoma, non-malignant urothelial tissue, four tumor-derived cell lines and in a non-malignant urothelial cell line (UROtsa). Quantitative reverse transcriptase PCR (qRT-PCR) of HERV-E4-1, HERV-K(HML-6) and HERV-T(S71-TK1) revealed a bias to lower HERV activity in carcinoma samples compared to non-malignant tissue. Determination of active HERV-E4-1 loci by cloning and sequencing revealed six HERV-E4-1 proviral loci that are differentially regulated in urothelial carcinoma cells and normal tissue. Two full-length HERV-E4-1 proviruses, HERV-Ec1 and HERV-Ec6, are located in antisense orientation in introns of the genes PLA2G4A and RNGTT, respectively. PLA2G4A encodes a cytosolic phospholipase A2 (cPLA2) that is dysregulated in many human tumors. PLA2G4A and HERV-Ec1 displayed reciprocal transcript levels in 7 of 11 urothelial carcinoma patients. Moreover, reciprocal shifts were observed after treatment of UROtsa cells with HERV-Ec1 and PLA2G4A-directed siRNAs or 5-aza-2'-deoxycytidine (aza-dC) pointing to an antagonistic regulation of PLA2G4A and HERV-Ec1 transcription in human urothelial cells. We suggest that transcription of HERV-Ec1 contributes to fine tuning of cPLA2 expression, thereby facilitating tumorigenesis.

The high incidence of JC virus infection in urothelial carcinoma tissue in Taiwan.

Human polyomaviruses, JC virus (JCV) and BK virus (BKV), usually remain latent in kidney and urothelial tissue after primary infection. Infection with human polyomavirus has still not been correlated conclusively with malignancy of kidney and urothelial tissue. The present study investigated further the possible relationship between JCV/BKV infection and urothelial carcinoma. Tissue samples were examined from 33 urothelial carcinomas and 5 renal cell carcinomas for JCV/BKV infection, using nested PCR with primers common to both JCV and BKV. The viral genotypes were further verified by endonuclease digestion and DNA sequencing following the PCR. In addition, immunohistochemistry and Western blotting were also performed to detect viral large tumor protein (LT) and the late capsid protein (VP1) in the tissue samples. The results from nested PCR showed that 90.1% (30/33) of the urothelial carcinomas samples and all of the renal cell carcinomas samples (5/5) were JCV DNA positive. Both archetypal and re-arranged JCV genotypes were detected. On the other hand, BKV DNA was detected in only one (3%) of the urothelial carcinoma tissue samples. The immunohistochemical results showed that 30% (10/33) of urothelial carcinoma tissues was stained positive for large tumor antigen (LT). However, the structural protein VP1 was not detectable in any of the tissue samples examined. The present study demonstrated that JCV is highly prevalent in urothelial carcinoma tissue as is the expression of large tumor antigen. Therefore, the findings support the hypothesis that JCV infection is associated with urothelial carcinoma.

Epstein-Barr virus DNA load in tumour tissues correlates with poor differentiation status in non-muscle invasive urothelial carcinomas.

OBJECTIVE: To detect the correlation between the clinical staging, grading and genomic Epstein-Barr virus (EBV) viral numbers in tumour tissues of urothelial carcinoma patients. PATIENTS AND METHODS: From June 2004 to May 2008, 60 urothelial carcinoma patients (50 cases of bladder carcinoma and 10 of upper tract urothelial carcinoma (UTUC) were enrolled in the study. Eight patients who underwent transurethral resection of prostate for prostate hyperplasia and two patients receiving nephrectomy for non-function kidney were used as normal controls. The EBV viral copy numbers in genomic DNA were evaluated using a real-time PCR-based study. The BamHI W region of the Namalwa cell line was constructed to the plasmid clone and was used as standard curve for absolute quantitative PCR (Q-PCR). RESULTS: Epstein-Barr virus DNA was detected in 56% (28/50) and 60% (6/10) of the bladder and UTUC patients, respectively. The EBV DNA could not be detected in the normal control group. By pooling the UTUC and bladder patients in stage Ta,T1, the high copy number in fixed genomic DNA amount (100 ng/20 µL) was correlated with the high grading in stage Ta,T1 urothelial carcinoma (P = 0.014). The overall grading was not statistically associated with EBV copy number (P = 0.25). Although the copy numbers between paired tumour and normal tissues were not statistically different (P= 0.169), there were more copies of EBV in the normal tissues adjacent to the tumours than in those free from urothelial carcinoma. There was no significant difference between recurrence of non-muscle invasive bladder cancer and the presence of EBV (P > 0.05). CONCLUSIONS: Epstein-Barr virus DNA could be detected in the genome of the urothelial carcinoma specimens. The poor differentiation status was correlated with the high load of the EBV genome in non-muscle invasive urothelial carcinoma. However, recurrence-free survival was not greater in EBV-positive patients than in EBV-negative patients.

[Urologic aspects of Polyomavirus infection]. / Aspects urologiques de l'infection à Polyomavirus.

JC virus (JCV) and BK virus (BKV) are human Polyomaviruses of the papovavirus family, which also includes a simian vacuolating virus 40 (SV40). Human Polyomaviruses were first isolated in 1971 from the brain (JCV) and urine (BKV) of two different patients. Human Polyomaviruses have a limited and specific tissue tropism infecting the renal tubular cells, the urothelium, the B cells and the brain cells. The virus infects the majority of the human population with seroconversion occurring during adolescence. The detection of the virus may be cytological, pathological, virological or immunological. Following a typically subclinical primary infection, Polyomavirus establishes a life-long persistent infection, especially in the urinary tract. BKV is known to reactivate and cause severe disease in immunosuppressed patients. The presence of Polyomavirus outside conditions of immunosuppression raises the question of its meaning and its therapeutic management. Given the ubiquitous nature of the virus and its strong association with cancer in animal models, they may play an etiological role in human malignancies. Here, we describe the biology of human Polyomaviruses, review their non-malignant and malignant potentials, and discuss the therapeutic aspect.

BK virus infection in association with posttransplant urothelial carcinoma.

OBJECTIVE: BK virus infection after transplantation is known to cause graft failure but the association with malignancies is controversial. METHODS: BK virus workup was performed for kidney recipients in our center under conditions of hematuria or acute deterioration of graft function. We reviewed the history and reported our treatment and the disease course of three patients with BK virus later diagnosed with urothelial carcinoma. RESULTS: All three patients received kidneys from China with immunosuppression using a calcineurin inhibitor and monoclonal antibodies. Synchronous bladder and upper-tract tumors were treated with surgery followed by intravesical chemotherapies. We tapered the immunosuppressants and changed to a sirolimus-based regimen. Intravesical chemotherapy and concurrent chemoradiotherapy were performed to prevent recurrence. All three patients now have functional grafts. CONCLUSION: BK virus infection may lead to tumorigenesis. Besides decreasing immunosuppressants, we should be more alert to the detection of malignancies in BK virus-reactivated recipients. Early aggressive treatment may be curative, preserving functional grafts.

Absence of Epstein-Barr virus infection in squamous cell carcinoma of upper urinary tract and urinary bladder.

OBJECTIVES: To address whether Epstein-Barr virus (EBV) infection may be involved in the carcinogenesis of squamous cell carcinoma of the upper urinary tract and urinary bladder (SCC-UB). EBV has been implicated in the genesis of a variety of human cancers, including urothelial carcinoma of the urinary bladder. METHODS: Whether EBV infection is related to SCC-UB carcinogenesis was investigated by in situ hybridization for EBV-encoded RNA and immunohistochemistry for latent membrane protein-1 in 26 cases of SCC-UB. RESULTS: EBV-encoded RNA and latent membrane protein-1 were identified in the control case of nasopharyngeal carcinoma. None of the SCC-UB cases had a nuclear signal of EBV-encoded RNA, and the cancer cells, normal urothelial cells, and inflammatory cells were all negative for latent membrane protein-1, irrespective of the site of SCC-UB. CONCLUSIONS: This study is the first to explore the role of EBV infection in SCC-UB. Our results suggest that EBV infection is not involved in the carcinogenesis of SCC of the renal pelvis, ureter, and urinary bladder.

Characterization of a panel of cell lines derived from urothelial neoplasms: genetic alterations, growth in vivo and the relationship of adenoviral mediated gene transfer to coxsackie adenovirus receptor expression.

PURPOSE: Cell lines have become an essential component for the investigation of cancer. We have developed a panel of cell lines derived from human urothelial cancers and we describe some of their important characteristics. MATERIALS AND METHODS: Ten human urothelial cancer cell lines were characterized by their growth in athymic nude mice, CAR expression and their susceptibility to adenoviral mediated transfer of the green fluorescence protein gene. TP53 mutation status and immunochemical analysis of p53, pRB and p16 were also examined. RESULTS: Five cell lines rapidly produced tumors in athymic nude mice. Two cell lines produced tumors in 1 month, 1 produced them in 3 months and 2 were nontumorigenic. The cell lines varied in CAR expression and in their susceptibility to adenoviral mediated gene transduction. There was no direct correlation between CAR expression and susceptibility to adenoviral mediated gene transduction. Seven cell lines had TP53 mutations, of which 2 had large deletions and did not express p53 protein by immunostaining. All cell lines expressed abnormal pRB by immunochemical analysis (3 had no staining and 7 had homogenously strong staining) and 8 did not express p16 (7 showed homogeneously strong pRB staining). CONCLUSIONS: Our panel of 10 human urothelial cell lines differed in genetic alterations, growth in nude mice, susceptibility to adenoviral mediated gene transduction, and expression of p53, p16 and pRB. The availability of various urothelial cancer cell lines with differing genotypic and phenotypic features will facilitate further research into bladder cancer.

Detection and expression of human BK virus sequences in neoplastic prostate tissues.

BK virus (BKV) is ubiquitous in the human population and establishes a lifelong, subclinical persistent infection in the urinary tract. When the immune system is compromised, it can cause severe disease in the kidney and bladder. Detection of BKV sequences in urinary tract neoplasms has led to the postulate that this virus may induce human oncogenesis through the function of its large tumor antigen (TAg). In this study, examination of prostate tumor tissue sections using in situ hybridization shows the presence of BKV sequences in atrophic epithelium. Solution polymerase chain reaction on DNA extracted from the tissues and sequence analysis of the products reveal the presence of BKV regulatory and early region sequences. In addition, immunohistochemical analysis using monoclonal antibodies specific to TAg or p53 shows the expression of TAg in some of the samples and p53 staining that can be correlated to TAg expression. Although the normal cellular localization of TAg and p53 is nuclear, double immunofluorescence labeling with anti-p53 and TAg antibodies indicates colocalization of p53 and TAg to the cytoplasm in the glandular epithelial cells of the sections. Although BKV DNA was found in benign and atrophic lesions, TAg and p53 coexpression was observed only in atrophic lesions.

Epstein-Barr virus infection in urothelial transitional cell carcinoma tissues.

OBJECTIVE: To explore a possible correlation of Epstein-Barr virus (EBV) infection with urothelial tumours, as the mutation of oncogenes, inactivation of tumour suppressor genes and viral infections may be important in the tumorigenesis of urothelial tumours, and EBV has been implicated in the pathogenesis of a variety of lymphoproliferative disorders and several epithelial neoplasms. MATERIALS AND METHODS: In all, 104 surgical specimens of transitional cell carcinoma (TCC) were obtained from urological operating rooms, fixed in 10% buffered formalin and processed for in situ hybridization using DNA probes, to locate the signal of EBV-encoded RNAs (EBERs). Immunohistochemistry with antibodies against CD20 and EBV-encoded latent membrane protein-1 (LMP-1) was used on EBER-positive tumour specimens. RESULTS: Thirty-one tumour specimens were positive for EBER hybridization in 100 evaluable specimens. Of these positive specimens, 21 were positive in both the infiltrating B lymphocytes and TCC tumour cells, seven only in B lymphocytes and three only in TCC cells. Of 31 EBER-positive tumour tissues, 26 (84%) had LMP-1, suggesting that EBER is more sensitive than LMP-1 for detecting EBV infection. CONCLUSION: There is a strong association between EBV infection and a significant proportion of primary urothelial TCC tumour cells.