Cytomorphology of lymphoepithelioma-like carcinoma of the urinary bladder: report of two cases

Lymphoepithelioma-like carcinoma (LELC) of the urinary bladder is a rare variant of high-grade urothelial carcinoma. Here, we report urine cytologic findings in two cases of this rare entity, the diagnosis of which was confirmed by histopathological examination of the resected tumors. The cytomorphologic features included large tumor cells with high nuclear to cytoplasmic ratios, vesicular chromatin, and prominent nucleoli, presented as single cells or intermixed with inflammatory cells. The differential diagnosis included otherwise typical high-grade urothelial carcinoma, reactive urothelial cells and rarely large cell lymphoma. The rarity of the tumor cells may impose a diagnostic challenge in urine specimen.     

High-grade urothelial carcinoma: comparison of SurePath liquid-based processing with cytospin processing

There is limited literature available comparing SurePath (SP) with conventional cytospins (CS) for urine cytology specimens, especially urothelial carcinoma. In this study, urinary tract cytology cases of high-grade urothelial carcinoma were assessed on SP and CS slides. Also, the morphologic differences of high-grade urothelial carcinoma between SP and CS were evaluated on a total of 35 cases of high-grade urothelial carcinoma. SP showed that the tumor cells tend to present as three-dimensional groups and have a smaller cell size than CS. In terms of nuclear features, SP and CS were found to be comparable in morphologic assessment of the tumor cells, with CS providing a slightly better visualization.     

Myeloid leukemia in a urine specimen: A case report and review of the literature

Urinary tract cytology has a long history of utilization for the diagnosis and follow‐up of tumors involving the urothelial tract. As expected, the most common tumor encountered in exfoliative urine cytology is urothelial carcinoma. While the sensitivity of urinary tract cytology for the diagnosis of low‐grade urothelial carcinomas is low, its sensitivity and accuracy for high grade urothelial carcinomas is much higher. However, nonurothelial malignancies, such as hematopoietic malignancies, can also be encountered in urine specimens. Leukemic cells in urine can be diagnosed readily by cytological examination in cases where more invasive procedures are difficult to perform. Additionally, cell block sections can be utilized to determine the immunocytochemical profile of the tumor cells to confirm the diagnosis. Herein we report a case of a 75‐year‐old man with a past medical history of acute myeloid leukemia (AML), who presented with congested heart failure and painless macroscopic hematuria. AML relapse was diagnosed. Cytological examination of the urine using a ThinPrep® smear, cytospin preparation, and immunohistochemical stains performed on the cell block sections were examined. Findings were consistent with leukemic cells of myeloid origin in the bladder washing specimen. Diagn. Cytopathol. 2014;42:700–704. © 2013 Wiley Periodicals, Inc.     

Transition between urothelial carcinoma in situ and non-invasive micropapillary carcinoma as a pivot connection between diverse morphologies of bladder carcinoma: a case report of urothelial carcinoma with villoglandular differentiation

Urothelial carcinoma has numerous histological variants, and these variants may coexist in a single case. Here, we present a case of a 70-year-old man with urothelial carcinoma of the bladder with a maximal diameter of 5 mm that involved micropapillary and plasmacytoid variants, with villoglandular differentiation. The presence of these variants was confirmed by pathological examination of a transurethral resection specimen, and high-grade urothelial carcinoma was found as a minor component. Although this bladder carcinoma was classified as pT1, cystoprostatectomy, urethrectomy, and lymphadenectomy were performed due to the presence of the micropapillary and plasmacytoid variants, which are known to be aggressive. Examination of a surgically resected specimen revealed no carcinoma. A transition between urothelial carcinoma in situ and non-invasive micropapillary carcinoma was found to be a pivot point connecting the diverse morphologies of this bladder carcinoma, from which there existed two pathways. One pathway was from urothelial carcinoma in situ to the plasmacytoid variant through invasive high-grade urothelial carcinoma, and the other was from non-invasive micropapillary carcinoma to urothelial carcinoma with villoglandular differentiation or to the micropapillary variant. This is the 16th reported case of urothelial carcinoma with villoglandular differentiation in the literature. As urothelial carcinoma with villoglandular differentiation is often associated with aggressive variants, as shown in our case, it should be reported whenever encountered in routine pathological practice.     

Small cell carcinoma of the urinary bladder: Distinctive cytological characteristics and Cyto-histologic correlation

Preoperative diagnosis in liquid-based cytology preparation in voided urine specimen and cyto-histologic correlation of small cell carcinoma of the urinary bladder has not been described in detail in the literature. A 79-year old male presented at our institution with gross hematuria. He was accurately diagnosed with small cell carcinoma of the bladder on liquid-based cytology in urine. The patient subsequently proceeded to transurethral resection of the bladder tumor, confirming the diagnosis. In this article, we present a detailed report of primary urothelial carcinoma with dominant neuroendocrine differentiation of the bladder describing the cytologic and histologic morphologic features, its differential diagnosis with a review of the literature.     

Fascin stain as a potential marker of invasiveness in carcinomas of the urinary bladder: a retrospective study with biopsy and cytology correlation

The evaluation of invasion in urothelial carcinomas of the urinary bladder cannot be determined on cytology and can be particularly challenging in biopsy cases with limited sampling. Recent studies of bladder resection specimens suggest that fascin overexpression may be a marker of aggressive urothelial carcinomas and can help facilitate the assessment of invasion. In this study, we evaluated urine cytology and corresponding biopsy specimens with proven invasive urothelial carcinoma for fascin expression by immunohistochemistry. Thirty‐five patients diagnosed with positive urine cytology and biopsy‐proven invasive urothelial carcinoma between January 2003 and February 2009 were identified. We found increased fascin expression in 100% (35/35) of SurePathTM&!trade; urine cytology preparations as well as 100% (35/35) of corresponding biopsy cases with invasive urothelial carcinoma. On urine cytology, cytoplasmic fascin staining was moderate to intense in malignant tumor cell clusters and single cells and not observed in benign urothelial cells. Staining in biopsy cases was generally intense and cytoplasmic and present in both the invasive (100%) and noninvasive (31%) components of the lesion. These findings uphold the association of increased fascin expression in invasive urothelial carcinomas of the urinary bladder. We furthermore demonstrate that fascin staining can be performed successfully on SurePathTM&!trade; urine cytology preparations in which increased fascin expression correlates with invasion on biopsy. While not a definitive marker of invasion, as it is observed in in situ carcinoma, we conclude that the utilization of fascin immunohistochemistry on urine cytology might serve as a useful adjunct in predicting invasiveness in subsequent biopsies. Diagn. Cytopathol. 2010. © 2010 Wiley‐Liss, Inc.     

Clinicopathological significance of TUBB3 in upper tract urothelial carcinoma and possible application in urine cytology

βIII-Tubulin, encoded by the TUBB3 gene, is a microtubule protein. We previously reported that TUBB3 is overexpressed in renal cell carcinoma. We investigated the clinicopathological significance of TUBB3 in upper tract urothelial carcinoma (UTUC) by immunohistochemistry. In normal tissue, TUBB3 expression was weak or absent. In contrast, TUBB3 overexpression was observed in urothelial carcinoma (UC) tissues in 51 (49%) of 103 UTUC cases. TUBB3 overexpression was associated with nodular/flat morphology, high-grade disease, high T stage, and a poor prognosis. Similar results were obtained in The Cancer Genome Atlas bladder cancer cohort. TUBB3 expression was also associated with high Ki-67 labeling index, CD44v9, HER2, EGFR, and p53 expression in UTUC. Among representative cancer-related molecules, TUBB3 was an independent predictor of progression-free survival and high-grade UC. Finally, using urine cytology samples, we analyzed TUBB3 expression by immunocytochemistry. TUBB3 expression was more frequently found in UC cells than in nonneoplastic cells. The diagnostic accuracy of urine cytology was improved when combined with TUBB3 immunostaining. The findings suggest the importance of TUBB3 in tumor progression and its potential application as a biomarker for high-grade disease and the prognosis of UC. Moreover, combination with TUBB3 immunostaining might improve the diagnostic accuracy of urine cytology.     

Urothelial and prostate carcinoma metastasizing to the same lymph node: a case report and review of the literature

We report herein a case of a collision tumor composed of high-grade urothelial carcinoma and a Gleason grade 3+4 prostate adenocarcinoma metastasizing to the same lymph node. After the patient underwent cystoprostatectomy for known urothelial carcinoma, he was incidentally discovered to have a second primary prostate tumor. Lymph node examination revealed that one node appeared to have metastatic foci from both primary tumors. The presence of 2 tumor types colliding in the same lymph node was confirmed using immunohistochemical stains, including monoclonal carcinoembryonic antigen, prostate-specific antigen, prostatic acid phosphatase, cytokeratins 7 and 20, and CD57. We also stained both primary tumors with the same panel as an internal control. Although 2 similar collision tumors have been reported in the literature in the past, neither used a battery of immunohistochemical stains to definitively distinguish one tumor from the other. Herein, we review the literature on urothelial and prostate collision tumors and some of the special stains used to distinguish them.     

Urothelial carcinoma of the urinary bladder with a component of acinar/tubular type differentiation simulating prostatic adenocarcinoma

We report a case of an 83-year-old man with a high-grade carcinoma of the urinary bladder who underwent cystoprostatectomy. The invasive carcinoma showed mixed, morphologically distinct patterns consisting of conventional high-grade urothelial carcinoma, glandular differentiation resembling enteric type adenocarcinoma, and acinar/tubular type differentiation, morphologically similar to Gleason grade 3 prostatic adenocarcinoma. Immunohistochemical studies revealed the acinar/tubular component of the tumor to be negative for prostate-specific antigen and prostatic acid phosphatase, but positive for cytokeratin 7, cytokeratin 20, high molecular weight cytokeratin (34 beta E12), and thrombomodulin, consistent with origin from the bladder rather than the prostate. Although bladder carcinomas composed of mixed morphologic patterns are not uncommon, to our knowledge, the presence of acinar/tubular type features simulating prostatic adenocarcinoma in such tumors has not been described elsewhere.     

Prostatic stromal sarcoma with rhabdoid features

Rhabdoid tumors have been reported in many different anatomic sites as an aggressive tumor and usually present with a rhabdoid tumor component (a composite tumor) rather than a pure rhabdoid tumor. Rhabdoid tumor in the prostate has been described only once in the prostatic region as a possible epithelial origin. Rhabdoid features in prostatic stromal sarcomas (PSSs) have never been described in the literature. Here, we report a case of a PSS with rhabdoid features. A 31-year-old man presented with a 4-month history of voiding difficulty and anal pain. Computed tomography of the abdomen revealed an ovoid mass in the prostate invading rectum and urinary bladder. A needle biopsy was diagnosed as an unclassified spindle cell sarcoma, and 2 cycles of adriamycin-based neoadjuvant chemotherapy were given, followed by radical prostatectomy. The prostatectomy specimen revealed a high-grade sarcoma with fascicles of highly cellular spindle cells and numerous mitoses with hemorrhage and necrosis. In areas, the tumor also contained sheets of loosely cohesive epithelioid cells with rhabdoid tumor component. Both spindle and rhabdoid tumor cells were positive for vimentin, CD34, and progesterone receptor and negative for desmin and cytokeratin immunostainings. The rhabdoid tumor cells retained INI1 expression. The tumor recurred in the bladder, and the patient died of sepsis. To the best of our knowledge, this is the first case of PSS with rhabdoid features. The tumor showed an aggressive clinical behavior with a short-term survival (7 months after diagnosis).     

ImmunoCyt/uCyt+ improves the sensitivity of urine cytology in patients followed for urothelial carcinoma.

ImmunoCyt/uCyt is a fluorescent test combining three monoclonal antibodies. In this study, it has been tested as a complement to cytology in the detection of urothelial carcinoma in urine. It has been performed simultaneously with standard cytology and cystoscopy on 870 urine analyses from one hospital. In 136 cases, one or more bladder tumors were found. Overall sensitivity of cytology, ImmunoCyt/uCyt and combined analyses reached 29, 74 and 84%, respectively, and overall specificity was 98, 62 and 61%. The negative predictive value of cytology, ImmunoCyt/uCyt and both analyses was 88, 93 and 95%, respectively, and the positive predictive value was 70, 26 and 29%. The sensitivity of cytology for low malignant potential neoplasms, low- and high-grade papillary carcinomas was 6, 18 and 53%, while it reached 71, 79 and 93% when combined with ImmunoCyt/uCyt. The sensitivity of cytology for stages Ta, T1, T2 and over and Tis tumors was 12, 67, 47 and 50%, while it reached 78, 83, 79 and 100% when combined with ImmunoCyt/uCyt. In the absence of tumor on cystoscopy but with positive ImmunoCyt/uCyt, 18% of patients developed a tumor, 2-6 months later. Of the 109 cases diagnosed as suspicious for malignancy by cytology, a tumor was present in 30 cases and ImmunoCyt/uCyt was positive in 22 (73%) of them. In conclusion, ImmunoCyt/uCyt may be used to postpone cystoscopies in patients followed for bladder cancer and may help to save cytologist and pathologist screening time.     

Osteoclast-rich undifferentiated carcinomas of the urinary tract.

Osteoclast-like giant-cell neoplasms of the urinary tract are rare. They are composed of ovoid or spindle-shaped mononuclear cells with evenly spaced osteoclast-like giant cells. Terminology, histogenesis, and biologic behavior of these tumors remain controversial. Six cases of osteoclast-like giant-cell neoplasms of the urinary tract were identified from the consultation files of two of the authors. Patients were all male and elderly (range 65-82), with the exception of one 39-year-old male. In all, 3/6 tumors developed in the bladder and 3/6 in the renal pelvis. Size ranged from 5 to 11 cm. One bladder and three renal pelvis tumors were high stage (pT3) at time of presentation. Adjacent to the osteoclast-like giant-cell neoplasm in the same specimen, all patients had urothelial carcinoma in situ and/or high-grade papillary urothelial carcinoma. Multinucleated cells had identical morphological and immunohistochemical properties of osteoclasts; positive for CD-68, LCA, CD51 and CD54, and negative for cytokeratins and EMA. Varying percentages of mononuclear cells expressed alpha-smooth muscle actin (4/6), desmin (1/6), S-100 (4/6), LCA (2/6) and CD68 (6/6). However, mononuclear cells were also positive for epithelial markers in 4/6 tumors (cytokeratins AE-1/AE-3, Cam 5.2, CK7 and/or EMA). p53 stained mononuclear tumor cells in three cases, paralleling the staining on the accompanying urothelial carcinoma. Ki-67 stained mononuclear tumor cells, but not osteoclast-like giant cells. Follow-up data were available in five cases. One patient developed recurrence of noninvasive urothelial carcinoma and is still alive. Four patients were dead due to disease within 15 months, three with distant metastases. The intimate association of these tumors with urothelial carcinoma along with their immunohistochemical profile supports an epithelial origin for the mononuclear cells and non-neoplastic reactive histiocytic lineage for the osteoclast-like giant cells.     

Current status of urinary cytology in the evaluation of bladder neoplasms

Pathologic examination of urinary specimens is increasingly recognized as an essential component of detection and monitoring for patients with bladder neoplasms. Among the available techniques, urinary cytology is the most useful. The current status of urinary cytology can be summarized as follows: 1. The demand for urinary cytology is steadily increasing as clinicians have realized the limitations of cystoscopy and even biopsy for monitoring bladder cancer patients, especially those having carcinoma in situ or receiving topical therapy. 2. Urinary cytology is currently an essential procedure for monitoring all patients with urothelial neoplasms and, if consistently used, can actually decrease the frequency with which patients need to be subjected to cystoscopy. 3. Even in moderately experienced hands, urinary cytology can detect almost all high-grade urothelial neoplasms. 4. The cytologic interpretation of low-grade transitional cell neoplasia requires expertise. These cells lack many of the features of malignancy, a source of confusion for the diagnostician but a positive factor for the patient since neoplasms composed of these cells are almost never aggressive. 5. The most useful type of urinary specimen for routine diagnostic interpretation is freshly voided, randomly collected urine. Catheterized specimens and bladder washings may yield more and better preserved cells, but no patient should be catheterized solely to obtain diagnostic material. 6. Preservation of urinary specimens in alcohols is not necessary unless prolonged storage is contemplated. Refrigeration to prevent bacterial growth and inhibit further cellular degeneration is required, however. 7. Cytologic details are best displayed with membrane filtration but other types of processing are adequate. The computer-programmed cytocentrifuge is currently most popular. 8. Optimal recognition of cytologic details requires some form of Papanicolaou staining; Romanovsky dyes are less desirable. 9. Urothelial cells with nuclear:cytoplasmic ratios of 1:2 or less should not be interpreted as malignant regardless of the degree of anaplasia of their nuclei. 10. Papillary aggregation is not a reliable feature of low-grade neoplasia in urinary samples. 11. Using appropriate criteria, the differential diagnosis of urothelial neoplasia versus the reactive/regenerative/reparative changes secondary to urinary stones can almost always be accomplished. 12. Alkylating agents such as Cytoxan, thio-TEPA, and mitomycin C produce characteristic but nonspecific changes in urothelial cells. These changes rarely mimic those of carcinoma. The diagnosis of urothelial neoplasia need not be confounded by previous treatment. 13. Flow cytometry and digitized image analysis are currently used for diagnostic interpretations of urinary specimens in selected centers. Their routine use must await further refinements in instrumentation and the formulation of more searching questions.     

Decoy cells and malignant cells coexisting in the urine from a transplant recipient with BK virus nephropathy and bladder adenocarcinoma

The search for decoy cells (DC) in urine is widely used as screening for BK virus (BKV) reactivation in transplant recipients. BKV cytopathic effect of DC must not be confused with high-grade urothelial carcinoma. This report presents a case of coexistence of DC and malignant cells in the urine from a transplant recipient with BKV-associated nephropathy (BKVN) and bladder adenocarcinoma. A 38-year-old female with type 1 diabetes mellitus and end-stage renal disease underwent a simultaneous pancreas and kidney transplant. Four years post-transplantation, BK virus studies were performed for renal dysfunction. Isolated DC and DC in casts were identified in urine. Also, the tests for BKV DNA were positive in serum and renal allograft biopsy. BKVN was treatment-resistant and the patient returned to hemodialysis. A kidney transplant nephrectomy was performed 2 years later. The next urine cytology showed, in addition to DC, other distinct cells with nuclear atypia highly suggestive of malignancy. Some cells showed both, malignant and DC features. A bladder adenocarcinoma was diagnosed on biopsy and BKV proteins were demonstrated on tumor cells, supporting a possible role for BKV in the oncogenic pathway in this clinical setting. The presence of DC in the urine from a transplant recipient is the hallmark of BKV activation, but it does not exclude the existence of carcinoma. Furthermore, the presence of highly atypical cells should raise, not eliminate, the possibility of neoplastic transformation of the bladder.     

Measuring the dimension of invasive component in pT1 urothelial carcinoma in transurethral resection specimens can predict time to recurrence

Recurrences of nonmuscle-invasive urothelial bladder cancer are very common following resection. Predictive histopathologic variables in transurethral resection of bladder tumor (TURBT) specimens are of particular importance especially in determining the behavior of lamina propria-invasive tumors (high grade T1 stage). A total of 110 patients who underwent TURBT for urothelial carcinoma (1997-2005) from a single institution were retrospectively reviewed. Amount of tumor invasion by urothelial carcinoma was assessed in terms of percentage, focality (focal vs multifocal), and dimension (DI, aggregate length of invasion). Of 110 patients, 39 (35%) were found to have invasive high-grade urothelial carcinoma, including 9 females. Mean age was 70 years (range, 56-94 years). Twenty-three patients with high-grade T1 urothelial carcinoma had available follow-up information. Recurrence rate in these 23 patients was 96% (22/23). Nearly all of the recurences (221/22, 95%) occurred within 1 year of the initial TURBT. There was an inverse correlation of DI with time to recurrence (P < .05; correlation coefficient, −0.47). Urothelial carcinoma with a greater DI (>0.5 cm) had a mean time to recurrence of less than 6 months. Percentage of tumor invasion and focality was not associated with recurrence. The aggregate length of invasion may be a prognostic variable for high-risk nonmuscle-invasive bladder cancer. Measuring “aggregate length of invasive tumor,” if further validated in larger studies, could provide a practical alternative in substaging pT1 tumors in TURBT specimens.     

Synchronous squamous cell carcinoma of the kidney,squamous cell carcinoma of the ureter,and sarcomatoid carcinoma of the urinary bladder: A case report

The author presents a unique case of a synchronous triple carcinoma of kidney, ureter, and urinary bladder. A 73-year-old man was admitted to our hospital because of hematuria and lumbago. Endoscopy and imaging modalities revealed a bladder tumor, a left ureter tumor, and a left kidney tumor. No other tumors were found in the body by imaging modalities. Cystectomy and left nephroureterectomy were performed. The bladder tumor was a large polypoid tumor consisting of pleomorphic sarcomatoid carcinoma (80%) and high-grade papillary urothelial carcinoma (20%), both invading the deep muscle layer. There were gradual merges between the two. The sarcomatous component was composed of malignant spindle, polygonal, and giant cells. Lymphovascular permeation was pronounced. Immunohistochemically, the sarcomatous element was positive for vimentin and various types of cytokeratins (CK), while the urothelial carcinoma element was positive for various types of CK and negative for vimentin. The ureter tumor was small and obstructed the ureter lumen. It was a pure squamous cell carcinoma without a urothelial component. The ureter tumor invaded the adventitia. A mild degree of lymphovascular invasion was recognized. Immunohistochemically, the tumor cells were positive for various types of CK but negative for vimentin. In the kidney, almost the entire kidney parenchyma was replaced by a tumor. The renal pelvis was broadly erosive but was free of apparent tumors. Histologically, the renal tumor was a pure squamous cell carcinoma without a urothelial component. Broad necrosis was present, and lymphovascular permeation was pronounced. The renal pelvis and calices were devoid of apparent tumor cells, but renal squamous cell carcinoma was present just beneath the pelvis and calices. Immunohistochemically, the kidney tumor was positive for various types of CK and negative for vimentin.     

The Paris System: achievement of a standardized diagnostic reporting system for urine cytology

Urinary tract cytology is a common diagnostic test used in the initial work up of bladder cancer. Since its inception as an utilizable diagnostic technique by Dr. Papanicolaou in 1945, urinary cytology has proven to be a cheap, easily obtained, and accurate method in the detection of high-grade urothelial carcinoma. Despite readily agreed upon features of high-grade urothelial carcinoma, a reproducible, universally accepted reporting method has not been attained. The Paris System for Reporting Urinary Cytology was developed to bring about a standardized reporting system with specific diagnostic categories and clear cytomorphologic criteria for the reliable diagnosis of high-grade urothelial carcinoma. This paper sets out to review the utility of urinary cytology, the current understanding of urothelial carcinoma, and the diagnostic categories of The Paris System. We finish with a review of the current literature regarding implementation of The Paris System.     

Coordinate expression of cytokeratins 7 and 20 in prostate adenocarcinoma and bladder urothelial carcinoma

We studied the expression of cytokeratin (CK)-7 and CK-20 in prostate adenocarcinoma and urothelial carcinoma and evaluated their usefulness for distinguishing high-grade forms of these tumors. We examined prostate adenocarcinoma in 59 radical prostatectomy specimens and in 10 autopsy specimens showing metastatic disease, and urothelial carcinoma of the bladder in 28 cystectomy specimens. Immunohistochemical staining for CK-7, CK-20, and prostate-specific antigen (PSA) was performed on paraffin sections. For prostate adenocarcinoma, 5 cases had only CK-7 positivity, 5 had only CK-20 focal positivity, 1 stained for both markers, and 48 were negative for both. PSA was positive in all but 1 poorly differentiated prostatic carcinoma. In the autopsy cases, PSA was expressed in the prostate and the metastatic tumors in most cases; few cases were focally positive for CK-7 or CK-20, but none was positive for both markers. For the urothelial tumors, CK-7 was the sole positive marker in 6 cases, and CK-20 in 1 case; 17 cases were positive for both, and 4 were negative for both. All urothelial carcinomas were PSA negative. Although PSA is useful for differentiating prostatic from urothelial carcinoma, CK-7 and CK-20 are helpful when both are positive, supporting the diagnosis of urothelial carcinoma. However, if only 1 marker is positive or both are negative, these markers have limited usefulness for distinguishing these carcinomas.     

Cytological significance of abnormal squamous cells in urinary cytology

The aim of this study was to evaluate the significance of abnormal squamous cells (ASCs) in urinary cytology to clarify whether finding of ASCs could improve diagnostic accuracy. A total of 3,812 urine specimens were reviewed. We focused on three parameters of ASCs, necrotic debris, and ASC clusters, and linked them to histological diagnosis and clinical information. ASCs were identified in 34 (0.9%) specimens from 21 different patients. The incidence of ASCs was higher in females than in males. The 34 urine specimens were categorized as voided urine (16 cases), bladder-catheterized urine (17 cases), and bladder-washed fluid (1 case). Six (28.6%) of 21 patients were histologically diagnosed as having combined urothelial carcinoma and squamous cell carcinoma (SCC). Eight patients (38.1%) were histologically diagnosed as having SCC originating from sites other than the urinary tract; those urine specimens showed ASCs that were likely to have been exfoliated from malignant lesions. Necrotic debris and ASC clusters were identified in 12 specimens (35.3%) from 11 patients and 4 specimens (11.8%) from 4 patients, respectively, from a total of 34 specimens. Our results indicate that a great amount of care is needed for cytological diagnosis when attempting to recognize ASCs in urine specimens because ASCs were identified in not only SCC of the bladder but also in carcinoma or nonmalignant lesions of nonurinary tracts. Necrotic debris was found not only in patients who had malignant bladder tumors but also in those who had malignant lesions in locations other than the bladder.