Micropapillary Variant Of Urothelial Carcinoma Research Articles

Cytologic features of micropapillary variant urothelial carcinoma in urinary tract cytology: Case series and review of literature.

The micropapillary variant of urothelial carcinoma (MPVUC) is rare and aggressive. Surgical specimens often show atypical micro-clusters (AMCs) of cells with hyperchromatic, pyknotic, peripheral, irregular nuclei with variable nuclear to cytoplasmic ratios. We reviewed urinary tract cytology (UTC) from patients with MPVUC and hypothesized that AMCs would be present similar to those in surgical specimens. The archives were searched from 2000 to 2020 for patients with surgical cases with either MPVUC or conventional high-grade urothelial carcinoma (HGUC) and with prior abnormal UTC. Two pathologists reviewed UTC cases and controls in a blinded manner for AMCs, with quantitation of none, low, moderate, and high. Interrater reliability was compared by quadratic weighted Cohen's Kappa test. The association between numerical average score and MPVUC status was determined by logistic regression. Five patients with invasive MPVUC, one patient with a noninvasive micropapillary component, and 15 control patients with conventional HGUC were included. All patients had prior or concurrent abnormal UTC samples. Increasing category of quantities of AMCs on cytology was associated with micropapillary status (OR 7.9, 95% CI 2.7-118, p= .045), with moderate agreement between raters (Cohen's Kappa 0.54, 95% CI 0.19-0.89, p= .004). In patients with MPVUC on surgical specimen, AMCs were frequently observed on cytology. Similar atypical clusters were observed in patients with nonmicropapillary HGUC, albeit at lower frequency. However, given the WHO recommendation to diagnose micropapillary only if an invasive micropapillary component is present, a specific diagnosis of MPVUC on UTC cannot be based solely on the presence of AMCs.

Expression and Prognostic Implication of PD-L1 in Patients with Urothelial Carcinoma with Variant Histology (Squamous Differentiation or Micropapillary) Undergoing Radical Cystectomy.

The expression and prognostic role of programmed death ligand-1 (PD-L1) on tumor-infiltrating immune cells (TICs) has not been determined in urothelial carcinoma (UC) with variant histology. We retrospectively reviewed 90 patients (44 with micropapillary variant of UC (MPUC) and 46 with UC with squamous differentiation (UCSD)) who underwent radical cystectomy between January 2013 and December 2019. The expression of PD-L1 in TICs was measured using the VENTANA (SP-142) immunohistochemistry assay and dichotomized using a 5% cutoff value (positive ≥ 5%). Kaplan–Meier survival analysis was used to estimate recurrence-free survival (RFS), and multivariable Cox proportional hazard models were used to identify factors predicting tumor recurrence. Overall, positive PD-L1 expression in TICs was confirmed in 50 of 90 (55.6%) patients (40.1% (18/44) of MPUC and 69.9% (32/46) of UCSD). RFS was significantly shorter in patients with positive PD-L1 expression in TICs than in those with negative PD-L1 expression both in MPUC (p = 0.005) and UCSD (p = 0.046). Positive PD-L1 expression in TICs was significantly associated with an increased risk of tumor recurrence in both MPUC (HR = 1.85; 95% CI: 1.323–2.672; p = 0.017) and UCSD (HR = 1.58; 95% CI: 1.162–2.780; p = 0.032). In conclusion, positive PD-L1 expression in TICs was significantly associated with poorer RFS in both MPUC and UCSD patients. Our results support the use of adjuvant immunotherapy in these patients if they test positive for PD-L1 in their TICs.

MP16-05 UTILIZATION OF INITIAL CYSTECTOMY VERSUS INTRAVESICAL BACILLUS CALMETTE-GUÉRIN FOR NON-MUSCLE INVASIVE MICROPAPILLARY UROTHELIAL CARCINOMA OF THE BLADDER

You have accessJournal of UrologyBladder Cancer: Non-invasive II (MP16)1 Sep 2021MP16-05 UTILIZATION OF INITIAL CYSTECTOMY VERSUS INTRAVESICAL BACILLUS CALMETTE-GUÉRIN FOR NON-MUSCLE INVASIVE MICROPAPILLARY UROTHELIAL CARCINOMA OF THE BLADDER Karishma Gupta, Danly Omil-Lima, Lin Chen, Wade Muncey, Irma Lengu, and Kyle Scarberry Karishma GuptaKarishma Gupta More articles by this author , Danly Omil-LimaDanly Omil-Lima More articles by this author , Lin ChenLin Chen More articles by this author , Wade MunceyWade Muncey More articles by this author , Irma LenguIrma Lengu More articles by this author , and Kyle ScarberryKyle Scarberry More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002001.05AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Micropapillary urothelial carcinoma is a rare and aggressive histologic variant of bladder cancer. Treatment guidelines recommend forgoing Bacillus Calmette-Guérin (BCG) therapy in favor of early radical cystectomy for non-muscle invasive micropapillary bladder cancer (NMI-MPBC) due to high rates of disease progression. We hypothesize that management of NMI-MPBC will vary across centers. METHODS: Patients with MPBC were identified from the National Cancer Database (2004-2017). Treatment trends and rates of pathological upstaging were identified. Bivariate and multivariate analyses were performed to assess differences in outcomes by treatment approach. RESULTS: 1,685 patients were diagnosed with MPBC during the study period with 531 identified to have localized Ta, T1, or Tis disease on presentation. BCG therapy was administered as initial therapy in 24.1% of NMI-MPBC patients and in 16.3% of non-micropapillary NMI-UC patients (p<0.001). Cystectomy was performed as primary therapy for NMI disease in 29.9% of MPBC and in 2.7% of non-micropapillary patients (p<0.001). Of the patients who underwent primary cystectomy, upstaging from NMI disease to T2-T4 disease was seen in 46.5% of the MPBC patients compared to 37.3% in patients with non-micropapillary disease (p=0.025). Upstaging to pathologic N1-3 disease was observed in 33.1% of MPBC patients compared to 11.9% non-micropapillary patients (p<0.001). Cystectomy as primary therapy for NMI-MPBC was more likely to be performed at academic (45.5%) compared to community cancer centers (15.6%) (p<0.001). On Cox regression analysis, adjusting for patient age, sex, race, comorbidities, and disease stage, care at academic cancer centers was associated with increased odds of having cystectomy as primary therapy compared to community cancer centers (OR = 4.29, 95% CI 2.73-6.76). Primary BCG therapy was not utilized any more frequently between academic (20.7%) and community cancer centers (27.1%) (p=0.093). CONCLUSIONS: The micropapillary variant of urothelial carcinoma is associated with increased odds of disease upstaging and node-positive disease. BCG is overutilized as primary treatment in this population. NMI-MPBC patients treated at academic centers were more likely to receive radical surgery as primary treatment compared to patients at community cancer centers. Source of Funding: N/A © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e297-e297 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Karishma Gupta More articles by this author Danly Omil-Lima More articles by this author Lin Chen More articles by this author Wade Muncey More articles by this author Irma Lengu More articles by this author Kyle Scarberry More articles by this author Expand All Advertisement Loading ...

膀胱微小乳頭型尿路上皮癌の 2 例

膀胱微小乳頭型尿路上皮癌の 2 例

Invasive micropapillary carcinoma of urinary bladder: a clinicopathological study.

Micropapillary variant of urothelial carcinoma (MPUC) is a rare but well-recognized tumor of the urinary bladder. Tumors with micropapillary areas accompanying conventional urothelial carcinoma are more aggressive compared to conventional urothelial carcinoma and show variable keratin 7, keratin 20 and human epidermal growth factor receptor 2 (Her 2)neu expression. The aim of the study was to analyze the clinical, morphological and immunohistochemical profile of MPUC. Transurethral resection of bladder tumor (TURBT) chips of seven cases of invasive MPUC with subsequent cystoprostatectomy specimens of five patients was reviewed. Epithelial membrane antigen (EMA), Keratin 7, Keratin 20, and Her 2 immunohistochemistry were performed in all cases. Follow-up information was available for all patients (2-36 months). All seven patients were male, and their ages ranged from 50 to 62 years. All cases presented with hematuria. The micropapillary pattern was seen in 20-95% of the tumor. All cases showed extensive lymphatic emboli with detrusor muscle invasion. Lymph node metastasis was present in all cases undergoing cystoprostatectomy except one. Keratin 7 and abluminal pattern of EMA positivity were seen in all cases. Keratin 20 was positive in five cases (71%), and Her 2neu positivity was seen in four cases. Three patients died 2, 3, and 6 months after initial diagnosis, among which two were Her 2 positive and one was Her 2 negative. There was no clear prognostic significance of Her 2 positivity. (1) MPUC is a rare but highly aggressive tumor. (2) Micropapillary is usually the predominant pattern. (3) Keratin 7 is expressed universally, whereas Keratin 20 expression is variable. (4) Her 2 expression has no clear influence on the survival.

Micropapillary variant of urothelial carcinoma – a review of the literature

The micropapillary variant of urothelial carcinoma is one of the variants of urothelial carcinoma that was added to the World Health Organization (WHO) classification in 2004. This variant of urothelial carcinoma is uncommon and, therefore, a number of practitioners have not yet encountered the tumour in their clinical practice. In view of this, the diagnostic features and the biological behaviour of this tumour are not well known by practitioners. This review documents the diagnostic features, management and outcome of the micropapillary variant of urothelial carcinoma. Various internet search engines were used to identify literature on the micropapillary variant of urothelial carcinoma, including case reports and case series, which formed the basis of the literature review. At least 500 cases of the micropapillary variant of urothelial carcinoma have been reported since it was first described in 1994. The gross morphology is variable and there are no special features to differentiate this variant from other variants or from conventional urothelial carcinoma. The micropapillary variant may be sessile, papillary, ulcerative or polypoid or may manifest as an infiltrative mass of variable size, ranging from microscopic to > 10 cm. The microscopic features of this variant of urothelial carcinoma exhibit an architecture that is reminiscent of the papillary configuration of ovarian papillary serous tumours. The nuclei of the micropapillary variant cells are commonly of high grade and show reverse polarity to the external surface of the tumour nests. A minority of the tumour-containing spaces represent actual lymphovascular invasion, which is supported by their characteristic immunohistochemical staining with endothelial markers. Lymphovascular invasion can be found in most cases of the invasive micropapillary variant of urothelial carcinoma if the specimens are adequately sampled, but a majority of the tumour-containing lacunae do not have endothelial lining and, therefore, do not represent true lymphovascular invasion. Psammoma bodies, which are common in ovarian papillary serous tumours, are rare in the micropapillary variant of urothelial carcinoma, and most of these tumours exhibit deep muscle invasion. Urine cytology exhibits papillary/spheroid clusters of tumour cells that have a high nuclear grade. The micropapillary variant of urothelial carcinoma is a rare and aggressive variant and may be under-reported as some pathologists may not be aware of its diagnostic features. Reports so far would indicate that this variant is associated with poor prognosis and adjuvant chemotherapy may have a questionable efficacy. Because of the rarity of this variant of urothelial carcinoma, there is no consensus opinion regarding the optimal treatment. Therefore, there is a need for urologists and oncologists throughout the world to report cases of the micropapillary variant of urothelial carcinoma so that the biological behaviour of the tumour can be ascertained. There is also a need for multicentre trials of treatment of this variant of urothelial carcinoma so that lessons can be learnt regarding the biological behaviour of the tumour and a consensus opinion can be established regarding the best treatment modality for such an apparently aggressive tumour.

280 Micropapillary variant of urothelial carcinoma in the upper urinary tract

280 Micropapillary variant of urothelial carcinoma in the upper urinary tract

Micropapillary urothelial carcinoma: Cytologic features in a retrospective series of urine specimens

Background:The micropapillary variant of urothelial carcinoma (uPC) is a rare variant of urothelial carcinoma that carries a poor prognosis. Definitive surgery may represent optimal management of low stage tumors. Urine cytology is indispensable in the screening and follow-up of urinary tract cancer. However, cytopathological criteria for diagnosis of uPC and its differentiation from conventional urothelial carcinoma (CUC) are not well-defined.Materials and Methods:Twenty-five cases of histologically confirmed micropapillary uPC from 21 patients were compared to 25 cases of histologically confirmed high-grade CUC.Results:In uPC cases, cell clusters were identified in 13 of 25 specimens from 10 patients. Six of the 13 specimens containing cell clusters corresponded to surgical pathology specimens in which micropapillary carcinoma accounted for at least 50% of total carcinoma. In contrast, only 1 of the 12 urine specimens devoid of cell clusters corresponded to surgical specimens in which micropapillary carcinoma accounted for at least 50% of total carcinoma. Cytomorphologic features of urinary specimens from patients with histologically confirmed micropapillary carcinoma were generally similar to those from patients with high-grade CUC, making it difficult to distinguish these entities in exfoliative urine specimens.Conclusions and Summary:Further investigation of the core cytopathological characteristics of uPC is warranted to refine its diagnostic criteria by exfoliative urine cytology.

Pathological response to neoadjuvant chemotherapy for muscle‐invasive micropapillary bladder cancer

To describe the pathological outcomes of patients with muscle-invasive micropapillary bladder cancer who have undergone neoadjuvant chemotherapy. A total of 82 patients with muscle-invasive micropapillary bladder cancer were treated between 1997 and 2010. After excluding those with metastatic disease, micropapillary histology only at radical cystectomy (RC), and chemo-radiation as primary treatment, 44 patients remained. All patients had ≥cT2 disease before chemotherapy/surgery. The median follow-up after RC was 28 months. Neoadjuvant chemotherapy was initiated in 29 (66%) patients and all patients underwent RC (93%) or partial cystectomy (7%). Micropapillary histology was diagnosed at first transurethral resection in 37 (84%) patients. Final RC pathology revealed pT0 in 15 (34%) patients and positive lymph nodes in 13 (31%) patients. Down-staging to pT0 occurred in 13 (45%) of those who received neoadjuvant chemotherapy compared with two (13%) of those who did not (P = 0.049). Patients with pT0 disease with micropapillary histology had higher overall survival rates (25 vs. 92%) and lower rates of bladder cancer recurrence (21 vs. 79%) at the 24-month follow-up. Almost half of the patients responded completely to neoadjuvant chemotherapy with a pT0 rate of 45%; therefore, patients with the micropapillary variant of urothelial carcinoma should not be excluded from consideration for neoadjuvant chemotherapy.

Cytological Findings of the Micropapillary Variant of Urothelial Carcinoma: A Comparison with Typical High-Grade Urothelial Carcinoma

BackgroundMicropapillary variant of urothelial carcinoma (MPUC) showed distinct pathologic features and aggressive behavior. The cytologic findings of MPUC are still indistinct. In this study, we evaluated the cytological findings of MPUC compared with those of high-grade urothelial carcinoma (HGUC).MethodsThe voided urine cytology of 8 cases of MPUC and 8 cases of HGUC was reviewed. Following cytological parameters were evaluated: cellularity, background, number of small, tight papillary clusters, small acinar structure, scattered single cells, cytoplasmic features, nuclear-to-cytoplasmic ratio, nuclear pleomorphism, nuclear membrane irregularity, hyperchromasia, chromatin pattern and nucleoli.ResultsCompared to that of HGUC, cytology of MPUC showed large numbers of small, tight papillary clusters, small acinar structure, few numbers of single cells, and hyperchromatic nuclei. Other parameters were similar between the two groups; both groups showed similar cellularity, dense or vacuolated cytoplasm, moderate to severe nuclear pleomorphism, irregular nuclear membrane, coarse granular chromatin, and small and prominent nucleoli.ConclusionsThe urine cytology of MPUCs showed smaller and tighter papillary cell clusters, more small acinar structures, fewer numbers of scattered single cells, and more hyperchromatic nuclei than that of HGUC. These features can help to distinguish MPUC and HGUC and offer an early cytological diagnosis of MPUC.

HER2 gene amplification occurs frequently in the micropapillary variant of urothelial carcinoma: analysis by dual-color in situ hybridization

Human epidermal growth factor receptor-2 (HER2) is a well-recognized growth-promoting factor in cancer, although its application to urothelial carcinoma has been limited because of a low frequency of gene amplification. We evaluated HER2 protein expression and gene amplification in micropapillary carcinoma, a rare but highly aggressive variant of urothelial carcinoma by dual-color in situ hybridization. Gene amplification was defined by a HER2:CHR17 ratio of ≥2.2; low and high levels of amplification were further defined as <2.5 and ≥2.5, respectively. Immunohistochemistry was used to determine HER2 protein expression using the American Society of Clinical Oncology/College of American Pathologists Guidelines of HER2 staining. Protein expression, gene amplification, and chromosome 17 aneusomy were compared by Jonchkeere–Terpstra and Cochran–Armitage trend tests. In all, 19 of the 20 micropapillary carcinoma samples yielded usable dual-color in situ hybridization and immunohistochemistry results for evaluation. Overall, 68% (n=13) demonstrated HER2 protein expression of 2+ to 3+ staining. Gene amplification was present in 42% of samples (n=8), with 100% correlation with 2+ and 3+ protein expression. Gene amplification and protein expression were significantly associated (P=0.01). Overall, 53% of samples (n=10) had aneusomy of chromosome 17. Chromosome 17 aneusomy was present in approximately half of the samples evaluated, suggesting inherent genomic instability in this variant of urothelial carcinoma. However, increased HER2:CHR17 ratios demonstrate increased HER2 expression due to amplification in the majority of micropapillary carcinomas. These results suggest that HER2-targeted therapy may be successful on the genomic level in patients with this disease.

Fine needle aspiration cytology of a case of micropapillary variant of urothelial carcinoma of bladder

Neoplastic urothelium has the capacity to demonstrate enormous plasticity. A variety of unusual morphological variants of urothelial carcinoma have been described. Micropapillary variant of urothelial carcinoma is a rare and recently described bladder tumor, associated with poor prognosis. We present the cytological features of micropapillary urothelial carcinoma in a 65-year-old man with bladder mass. The cytological features include tightly cohesive clusters of micropapillary component admixed with urothelial carcinoma. Histopathological sections showed small nests of tumor cells residing within the lacunae. Establishing a diagnosis of micropapillary urothelial carcinoma indicates a high-grade and high-stage tumor with poor outcome, requiring an aggressive therapy. It is thus important for the cytopathologist to recognise micropapillary variant of urothelial carcinoma, for early and better management of patients with bladder tumor.

Invasive micropapillary urothelial carcinoma of the bladder

In this report, we present the clinicopathologic features of 13 cases of the invasive micropapillary variant of urothelial carcinoma. This is a rare and aggressive variant of bladder cancer recognized by the current World Health Organization classification of urologic tumors. The micropapillary component varied from 50% to 100% of the tumor specimen; in 10 cases, the micropapillary component composed greater than 70% of the tumor, with 5 cases showing pure micropapillary carcinoma. The architectural pattern of the tumor varied from solid expansile nests with slender papillae within tissue retraction spaces to pseudoglandular growth with prominent ring-like structures (2 cases, 15%) and invasive micropapillary carcinoma with squamous differentiation (2 cases, 15%); a streaking solid architectural pattern of micropapillary carcinoma was additionally present in 2 cases (15%). At histology, the individual tumor cells had abundant eosinophilic cytoplasm and nuclei with prominent nucleoli and irregular distribution of chromatin, and frequent mitotic figures. Most neoplastic cells had nuclei of low to intermediate nuclear grade with occasional nuclear pleomorphism. Eight mixed cases had concurrent conventional high-grade urothelial carcinoma with squamous or glandular differentiation in 3 and 1 case(s), respectively. All patients had advanced-stage cancer (>pT2), and 8 (62%) had lymph node metastasis. Immunohistochemical staining demonstrated that both micropapillary and associated conventional urothelial carcinomas were positive for MUC1 and 2, cytokeratin 7, PTEN, p53, and Ki-67. Her2Neu, uroplakin, cytokeratin 20, 34betaE12, CA125, and p16 were positive in 4, 10, 8, 7, 3, and 3 cases, respectively. MUC5A, MUC6, and CDX2 were negative in all micropapillary cases. Follow-up information was available in all cases (range, 2-21 months; mean, 10 months). Eleven of patients died of disease from 2 to 14 months, and 2 patients were alive with disease at 14 and 21 months. Univariate statistical analysis showed survival differences between invasive micropapillary and conventional urothelial carcinomas (P < .0001). In summary, invasive micropapillary variant of urothelial carcinoma is an aggressive variant associated with poor prognosis that presents at an advanced clinical stage. The immunophenotype of invasive micropapillary carcinoma supports urothelial origin; the immunoreactivity to Her2Neu and PTEN might be relevant in terms of future targeting therapy. The morphologic diversity of micropapillary carcinoma may represent a diagnostic pitfall in limited samples, where its distinction from conventional urothelial carcinoma is critical for its clinical management.

Micropapillary variant of urothelial carcinoma in the upper urinary tract: a clinicopathologic study of 11 cases.

Abstract Context.—Micropapillary urothelial carcinoma (MPUC) is a rare variant of urothelial carcinoma. Most studies of MPUC have focused on the urinary bladder, but MPUC of the upper urinary tract remains to be investigated. Objective.—To investigate the pathologic features and clinical significance of MPUC in the upper urinary tract. Design.—We searched the pathology files at our institution and identified 11 cases of MPUC of the upper urinary tract. The histology slides were reviewed, and the clinical information was obtained by review of medical charts. Results.—The average age of the patients was 64.2 years (range, 22–76 years). The tumors were located in the renal pelvis (n = 5), ureter (n = 4), and ureteropelvic junction (n = 2). In all cases, MPUC accounted for an average of 45% (range, 10%–80%) of the tumor and was associated with conventional urothelial carcinoma. Lymphovascular invasion was present in all cases, and metastasis to lymph node was present in 4 of 5 patients whose lymph nodes were ...

Micropapillary Variant of Urothelial Carcinoma in the Upper Urinary Tract: A Clinicopathologic Study of 11 Cases

Micropapillary urothelial carcinoma (MPUC) is a rare variant of urothelial carcinoma. Most studies of MPUC have focused on the urinary bladder, but MPUC of the upper urinary tract remains to be investigated. To investigate the pathologic features and clinical significance of MPUC in the upper urinary tract. We searched the pathology files at our institution and identified 11 cases of MPUC of the upper urinary tract. The histology slides were reviewed, and the clinical information was obtained by review of medical charts. The average age of the patients was 64.2 years (range, 22-76 years). The tumors were located in the renal pelvis (n = 5), ureter (n = 4), and ureteropelvic junction (n = 2). In all cases, MPUC accounted for an average of 45% (range, 10%-80%) of the tumor and was associated with conventional urothelial carcinoma. Lymphovascular invasion was present in all cases, and metastasis to lymph node was present in 4 of 5 patients whose lymph nodes were dissected. Two patients presented with pT2 disease, and both were alive without evidence of disease at 85 and 119 months after surgery. The other 9 patients presented with pT3 or pT4 disease: 4 of them died of disease at an average of 18 months; 4 surviving patients developed distant metastases; and 1 surviving patient with limited follow-up (6 months) showed no evidence of disease. Micropapillary urothelial carcinoma of the upper urinary tract often presents at an advanced stage with lymphovascular invasion and distant metastasis. The presence of MPUC, even focal, indicates a poor clinical course.

Micropapillary Carcinoma of the Renal Pelvis and Ureter

MPC located in the upper urinary tract is rare with only 2 cases reported to date. We report clinical and histopathological data on 26 patients to increase the knowledge of this rare entity. A clinical and histopathological review was performed in 943 patients with a neoplasm in the renal pelvis or ureter, diagnosed between 1971 and 1998. We identified 26 patients with MPC. No patients were alive at the end of the study. Of the patients 11 had greater than 50% MPC and 15 had focal MPC (at least 10%). The incidence was 2.8%. Median patient age at diagnosis was 69 years (range 54 to 88) and the male-to-female ratio was 17:9. All except 4 patients had stage T3 disease or higher. Carcinoma in situ was identified in 64% of cases and vascular invasion was present in 81%. A total of 20 patients (77%) died of disease and only 7 survived longer than 5 years. The prognosis is poor since most patients with MPC of the renal pelvis and ureter initially present with advanced disease. Stage for stage the prognosis is not different from that in nonMPC urothelial cell carcinoma. Surgery is curative in less advanced cases. However, radiotherapy and systemic chemotherapy appear to be ineffective.

Mixed micropapillary and trophoblastic carcinoma of bladder: report of a first case with new immunohistochemical evidence of urothelial origin

The micropapillary variant of urothelial carcinoma has a reported incidence of 0.7%. Trophoblastic urinary carcinoma is very rare, with roughly 30 cases reported during the last century. This is the first report of mixed micropapillary and trophoblastic bladder carcinoma. A 45-year-old man presented with gross hematuria. His tumor contained choriocarcinomatoid areas with syncytiotrophoblasts, classic micropapillary carcinoma, conventional high-grade urothelial carcinoma, and flat carcinoma in situ. He underwent radical surgery; tumor stage was T4N2M0. Despite postoperative combination chemotherapy, he developed pulmonary and retroperitoneal metastases and died 20 months after presentation. The tumor was immunopositive for human chorionic gonadotropin and human placental lactogen in trophoblast and for cytokeratin 20 and high-molecular-weight cytokeratin in all tumor components. Because high-molecular-weight cytokeratin is expressed by urothelium but is rarely found in placental trophoblast or germ-cell choriocarcinoma, its presence in trophoblastic bladder carcinoma is new evidence that the latter is a transformed neoplasm of urothelial origin.