Micropapillary variant of transitional cell carcinoma of the urinary bladder. Histologic pattern resembling ovarian papillary serous carcinoma

The 2016 WHO Classification of Tumours of the Urinary System and Male Genital Organs-Part B: Prostate and Bladder Tumours

It has been 12 yr since the publication of the last World Health Organization (WHO) classification of tumours of the prostate and bladder. During this time, significant new knowledge has been generated about the pathology and genetics of these tumours. Intraductal carcinoma of the prostate is a newly recognized entity in the 2016 WHO classification. In most cases, it represents intraductal spread of aggressive prostatic carcinoma and should be separated from high-grade prostatic intraepithelial neoplasia. New acinar adenocarcinoma variants are microcystic adenocarcinoma and pleomorphic giant cell adenocarcinoma. Modifications to the Gleason grading system are incorporated into the 2016 WHO section on grading of prostate cancer, and it is recommended that the percentage of pattern 4 should be reported for Gleason score 7. The new WHO classification further recommends the recently developed prostate cancer grade grouping with five grade groups. For bladder cancer, the 2016 WHO classification continues to recommend the 1997 International Society of Urological Pathology grading classification. Newly described or better defined noninvasive urothelial lesions include urothelial dysplasia and urothelial proliferation of uncertain malignant potential, which is frequently identified in patients with a prior history of urothelial carcinoma. Invasive urothelial carcinoma with divergent differentiation refers to tumours with some percentage of "usual type" urothelial carcinoma combined with other morphologies. Pathologists should mention the percentage of divergent histologies in the pathology report.

PATIENT SUMMARY

Intraductal carcinoma of the prostate is a newly recognized entity in the 2016 World Health Organization classification. Better defined noninvasive urothelial lesions include urothelial dysplasia and urothelial proliferation of uncertain malignant potential.

Gene Expression Profile of the Clinically Aggressive Micropapillary Variant of Bladder Cancer

BACKGROUND

Progression of conventional urothelial carcinoma of the bladder to a tumor with unique microscopic features referred to as micropapillary carcinoma is coupled with aggressive clinical behavior signified by a high propensity for metastasis to regional lymph nodes and distant organs resulting in shorter survival.

OBJECTIVE

To analyze the expression profile of micropapillary cancer and define its molecular features relevant to clinical behavior.

DESIGN, SETTING, AND PARTICIPANTS

We retrospectively identified 43 patients with micropapillary bladder cancers and a reference set of 89 patients with conventional urothelial carcinomas and performed whole-genome expression messenger RNA profiling.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The tumors were segregated into distinct groups according to hierarchical clustering analyses. They were also classified according to luminal, p53-like, and basal categories using a previously described algorithm. We applied Ingenuity Pathway Analysis software (Qiagen, Redwood City, CA, USA) and gene set enrichment analysis for pathway analyses. Cox proportional hazards models and Kaplan-Meier methods were used to assess the relationship between survival and molecular subtypes. The expression profile of micropapillary cancer was validated for selected markers by immunohistochemistry on parallel tissue microarrays.

RESULTS AND LIMITATIONS

We show that the striking features of micropapillary cancer are downregulation of miR-296 and activation of chromatin-remodeling complex RUVBL1. In contrast to conventional urothelial carcinomas that based on their expression can be equally divided into luminal and basal subtypes, micropapillary cancer is almost exclusively luminal, displaying enrichment of active peroxisome proliferator-activated receptor γ and suppression of p63 target genes. As with conventional luminal urothelial carcinomas, a subset of micropapillary cancers exhibit activation of wild-type p53 downstream genes and represent the most aggressive molecular subtype of the disease with the shortest survival. The involvement of miR-296 and RUVBL1 in the development of micropapillary bladder cancer was identified by the analyses of correlative associations of genome expression profiles and requires mechanistic validation.

CONCLUSIONS

Micropapillary cancer evolves through the luminal pathway and is characterized by the activation of miR-296 and RUVBL1 target genes.

PATIENT SUMMARY

Our observations have important implications for prognosis and for possible future development of more effective therapies for micropapillary bladder cancer.

Overexpression of Vascular Endothelial Growth Factor A in Invasive Micropapillary Colorectal Carcinoma

BACKGROUND

Invasive micropapillary carcinoma (IMPC) is a rare variant of colorectal cancer with an adverse prognosis. "Retraction artifact" around tumor cells is a feature of IMPC. The aim of this study was to assess the nature of the retractions around the tumor cells and to describe the histopathological features of a group of 18 cases of IMPC.

METHODS

A pathology review of 128 consecutive colorectal cancers identified 18 cases of histologically proven IMPC using 5% of the total tumor volume comprised of a micropapillary component as the diagnostic criterion. Immunostains for D2-40, CD31, CD34, vascular endothelial growth factor A (VEGF-A), and mucin 1 (MUC-1) were performed using the avidin-biotin complex method.

RESULTS

Cases of IMPC were characterized by pseudomicropapillae surrounded by lacunar-like clear spaces. These structures exhibited the inside-out growth pattern as highlighted by MUC-1 staining. The lining of the lacunar spaces was immunoreactive to CD31 but not CD34 or D2-40, indicating that they are neovascular structures. Furthermore, the tumor cells strongly and diffusely expressed VEGF-A.

CONCLUSIONS

The strong coexpression of VEGF-A and CD31 suggests a prominent role of neoangiogenesis in these tumors.

Cervical adenocarcinoma with stromal micropapillary pattern

Adenocarcinoma with a stromal micropapillary pattern (SMP) has been described in various organs, but not in the uterus. We encountered a case of uterine cervical carcinoma with SMP. A54-year-old Japanese woman was referred to the hospital with abnormal vaginal bleeding. The cervical cytodiagnosis was adenocarcinoma with features resembling serous adenocarcinoma. Cervical cytology showed many small clusters of tumor cells, present in up to two or three layers, composed of atypical cells with markedly increased nucleus: cytoplasm ratios. A radical hysterectomy with bilateral adnexectomy and retroperitoneal lymph node dissection was performed. Microscopically, the tumor was composed predominantly of adenocarcinoma with SMP. The outer surface of the SMP cell clusters showed membranous expression of mucin-1 (MUC-1). Many lymph node metastases were detected. The tumor was diagnosed as a cervical adenocarcinoma with SMP and coexistent squamous cell carcinoma in situ. The pathology was classified as T1b1N1M1, stage IVB. The patient underwent postoperative adjuvant chemotherapy and is without local recurrence or distant metastasis 48 months after the operation. To the best of our knowledge, this is the first reported case of cervical adenocarcinoma with SMP.

A case report of urothelial carcinoma with combined micropapillary and plasmacytoid morphology in the urinary bladder

A case of combined micropapillary and plasmacytoid urothelial carcinoma (UC) of the urinary bladder is presented for a 74-year-old male who was admitted to the hospital with gross hematuria and multifocal papillary bladder tumors. Abdominal computed tomography showed a large enhancing mass on the left lateral and anterior wall of the urinary bladder, which was highly suspicious for extravesicular extension and focal extension of the anterior lesion to the pubic bone. In voided urine, cancer cells were scattered as micropapillae or nests as well as single cells on the low power view. On a higher power view, micropapillae or nests were composed of pleomorphic, high grade tumor cells with an inverted nuclear arrangement and with acinar structures occasionally identified. Single cells were discohesive and large with a thick cytoplasm and eccentrically located nuclei. Histologically, the tumor from the resected bladder showed diffusely infiltrating micropapillae or nests with a surrounding halo and dense singly-scattered plasmacytoid cells. Immunohistochemically, the cancer cells were positive for cytokeratin-7 and cytokeratin-20 but negative for S-100, leukocyte common antigen, and vimentin. At the time of radical cystectomy, severe adhesions and peritoneal metastases were found and the surgery was discontinued. The patient received systemic chemotherapy, but died of bladder cancer 14 months after surgery.

Optimal treatment of non-muscle invasive urothelial carcinoma including perioperative management revisited

Non-muscle invasive urothelial carcinoma is a heterogeneous disease that requires the practicing urologist to implement a variety of surgical and non-surgical treatment strategies. The disease course can range from recurrent low grade papillary disease to aggressive disease concerning for progression from initial presentation. Depending on the particular patient and goals of care, treatments similarly span the range from minimally invasive fulgurations to immediate radical cystectomy. For most patients some form of intravesical therapy will bridge the gap between transurethral resections (TUR) and radical surgery. Recent advances in the field continue to emphasize the importance of quality TUR and its strong impact on outcomes. In addition, continued research to optimize intravesical therapies has provided more information about how, when, and in whom these agents should be utilized to enhance their efficacy. This review covers the current state of NMIBC and the standards of care for the management of this disease.

Pulmonary metastasis in a patient with simultaneous bladder cancer and relapsing granulomatosis with polyangiitis

Patient: Male, 70

Final Diagnosis: Metastatic micropapillary urothelial carcinoma

Symptoms: Dry cough • dyspnea • hematuria

Medication: Cyclophosphamide

Clinical Procedure: Pulmonary wedge resection

Specialty: Pulmonology

Phagocytosis (cannibalism) of apoptotic neutrophils by tumor cells in gastric micropapillary carcinomas

AIM: To identify those with a micropapillary pattern, ascertain relative frequency and document clinicopathological characteristics by reviewing gastric carcinomas.

METHODS: One hundred and fifty-one patients diagnosed with gastric cancer who underwent gastrectomy were retrospectively studied and the presence of a regional invasive micropapillary component was evaluated by light microscopy. All available hematoxylin-eosin (HE)-stained slides were histologically reviewed and 5 tumors were selected as putative micropapillary carcinoma when cancer cell clusters without a vascular core within empty lymphatic-like space comprised at least 5% of the tumor. Tumor tissues from these 5 invasive gastric carcinomas were immunostained using an anti-mucin 1 (MUC1) antibody (clone MA695) to detect the characteristic inside-out pattern and with D2-40 antibody to determine the presence of intratumoral lymph vessels. Detection of intraepithelial neutrophil apoptosis was evaluated in consecutive histological tissue sections by three independent methods, namely light microscopy with HE staining, the conventional terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) method and immunohistochemistry for activated caspase-3 (clone C92-605).

RESULTS: Among 151 gastric cancers resected for cure, 5 (3.3%) were adenocarcinomas with a micropapillary component. Four of the patients died of disease from 6 to 23 mo and one patient was alive with metastases at 9 mo. All patients had advanced-stage cancer (≥ pT2) and lymph node metastasis. Positive MUC1 immunostaining on the stroma-facing surface (inside-out pattern) of the carcinomatous cluster cells, together with negative immunostaining for D2-40 in the cells limiting lymphatic-like spaces, confirmed the true micropapillary pattern in these gastric neoplasms. In all five cases, several micropapillae were infiltrated by neutrophils. HE staining, TUNEL assay and immunostaining for caspase-3 demonstrated apoptotic neutrophils within cytoplasmic vacuoles of tumor cells. These data suggest phagocytosis (cannibalism) of apoptotic neutrophils by micropapillary tumor cells. Tumor cell cannibalism is usually found in aggressive tumors with anaplastic morphology. Our data extend these observations to gastric micropapillary carcinoma: a tumor histotype analogously characterized by aggressive behavior and poor prognosis. The results are of interest because they raise the intriguing possibility that neutrophil cannibalism by tumor cells may be one of the mechanisms favoring tumor growth in gastric micropapillary carcinomas.

CONCLUSION: This is the first study showing phagocytosis (cannibalism) of apoptotic neutrophils by tumor cells in gastric micropapillary carcinomas.

Update for the practicing pathologist: The International Consultation On Urologic Disease-European association of urology consultation on bladder cancer

The International Consultations on Urological Diseases are international consensus meetings, supported by the World Health Organization and the Union Internationale Contre le Cancer, which have occurred since 1981. Each consultation has the goal of convening experts to review data and provide evidence-based recommendations to improve practice. In 2012, the selected subject was bladder cancer, a disease which remains a major public health problem with little improvement in many years. The proceedings of the 2nd International Consultation on Bladder Cancer, which included a 'Pathology of Bladder Cancer Work Group,' have recently been published; herein, we provide a summary of developments and consensus relevant to the practicing pathologist. Although the published proceedings have tackled a comprehensive set of issues regarding the pathology of bladder cancer, this update summarizes the recommendations regarding selected issues for the practicing pathologist. These include guidelines for classification and grading of urothelial neoplasia, with particular emphasis on the approach to inverted lesions, the handling of incipient papillary lesions frequently seen during surveillance of bladder cancer patients, descriptions of newer variants, and terminology for urine cytology reporting.

Is Immediate Radical Cystectomy Necessary for All Patients with Non-Muscle-Invasive Micropapillary Bladder Cancer?

INTRODUCTION

We aim to review the outcomes of micropapillary urothelial carcinoma (MPUC) of the bladder from a single institution. The hypothesis is that non-muscle-invasive (NMI) MPUC may have a heterogeneous prognosis, and detailed pathological analysis may identify patients that could be managed without immediate cystectomy.

PATIENTS AND METHODS

This is a retrospective analysis of patients presenting with MPUC in a primary transurethral resection specimen (n = 40). The pattern of micropapillary (MP) differentiation [surface/non-invasive (sMP) or invasive (iMP)], extent of MP differentiation and lymphovascular invasion (LVI) were correlated with overall survival (OS), recurrence-free survival and upstaging at re-resection.

RESULTS

Sixteen of 40 patients died after a median follow-up of 37 months. Tumour stage was strongly predictive of OS (p < 0.0001). LVI was associated with increased mortality (hazard ratio 12.4, 95% CI: 3.5-44.5, p = 0.0001), higher pathological stage (p = 0.001), lymph node involvement (p = 0.001) and iMP differentiation (p = 0.006). In NMI patients not undergoing cystectomy (n = 17), NMI-sMP compared with NMI-iMP differentiation was associated with an improved OS when compared with iMP (63 vs. 47 months, p = 0.05).

CONCLUSIONS

MPUC is an aggressive variant of urothelial carcinoma (UC). Similar to conventional UC, LVI associated with MPUC is an adverse prognostic indicator. iMP is a morphological marker for LVI. Histopathological reports should distinguish between sMP and iMP differentiation.

The presence of extensive retraction clefts in invasive breast carcinomas correlates with lymphatic invasion and nodal metastasis and predicts poor outcome: a prospective validation study of 2742 consecutive cases

We previously reported that the presence of extensive retraction clefts (RC) in breast cancers correlates with increasing tumor size and grade as well as lymphatic tumor spread and predicts poor outcome. This study is a prospective validation of our prior results. Consecutive cases of invasive breast carcinoma (n=2742) were reviewed to determine the diagnoses, including histologic type, grade, presence of lymphovascular invasion (LVI), and extent of RC. No differences were found in the extent of RC between corresponding core needle biopsy and surgical samples. Extent of RC showed a significant correlation with tumor size, grade, LVI, and nodal metastasis in both core needle biopsy and surgical specimens. These associations remained significant in subset analyses of small (≤1 cm), node-negative and node-positive tumors. Extensive RC predicted poor recurrence-free (P<0.0001) and overall (P<0.0001) survival and remained significant in subset analyses of node-negative (P=0.0015 and 0.0021, respectively) and node-positive (P=0.0039 and 0.0214, respectively) cases. Carcinomas without LVI but extensive RC were associated with better outcome than carcinomas with LVI but worse than those without LVI and low RC. This prospective study confirms that the presence of extensive RC in invasive breast carcinomas correlates with aggressive tumor features and lymphatic tumor spread. Extensive RC appears to be an independent factor predictive of poor outcome in node-negative and node-positive disease. Our results support the hypothesis that RCs are the morphologic reflection of biological changes in tumor cells playing a role in lymphatic tumor spread and likely represent an early stage of LVI with similar clinical implications.

Prognostic factors in urothelial carcinoma of the bladder: histologic and molecular correlates

Histologic characterization of urothelial carcinoma remains the most important factor for determining a patient's prognosis and treatment regimen. However, challenges remain in accurately staging and grading many tumors, and substaging remains controversial. Recently, significant insight has been gained into the molecular pathogenesis of bladder cancer that may aid in further characterizing urothelial carcinoma. Many molecular biomarkers have been clinically validated, and some have been shown to provide more prognostic information than histology alone. In addition, a subset of these markers may even represent targets for molecular therapy. Here, we review histologic staging and grading of urothelial carcinoma, as well as discuss many of the clinically relevant molecular markers. As each urothelial carcinoma likely represents a unique biological entity, the need for complete histologic and molecular characterization of these tumors is necessary as we enter the age of personalized medicine.

Prevalent and up-regulated vimentin expression in micropapillary components of lung adenocarcinomas and its adverse prognostic significance

The factors conferring the increased malignancy on lung adenocarcinoma with micropapillary component (AC-MPC) remain to be elucidated. On proteomics based on 2-dimensional gel electrophoresis, 19 proteins differentially expressed by more than 1.5-fold between AC-MPC and conventional adenocarcinoma (CAC); in particular, vimentin, one of the proteins, was 3.5-fold up-regulated in AC-MPC. Subsequent semi-quantitative investigation by immunohistochemistry with large cohorts comprised 101 AC-MPC and 119 CAC, respectively, of different stages revealed that vimentin was expressed in MPC of 95 (94.1%) AC-MPC and the expression scores were higher than those of well- and moderately differentiated CAC, as well as the background non-MPC of the AC-MPC (P < 0.0001), but not significantly different from those of poorly differentiated CAC (P = 0.561). Even within the AC-MPC entity, higher vimentin expression was correlated with more frequent vascular invasion and more advanced node metastasis (P < 0.02), and multivariate analysis showed that high vimentin expression and worse node statuses were independent indicators of adverse prognosis (P < 0.048). In conclusion, vimentin expression is prevalent and markedly up-regulated in MPC, which might reflect the biological essence of poorer differentiation or dedifferentiation of MPC, and this might have a role in the acquisition and increase of invasiveness and consequent more malignant nature of MPC.

External beam radiotherapy for focal lymphoepithelioma-like carcinoma in the urinary bladder: a case report and literature review

Lymphoepithelioma is a malignant epithelial tumor in the nasopharynx characterized by prominent lymphoid infiltration. Carcinomas that resemble lymphoepitheliomas have been called lymphoepithelioma-like carcinomas and have been reported in other organs. A tumor in the bladder is categorized by the percentage of the total area occupied by the lymphoepithelioma-like carcinoma pattern, with the prognosis dependent on the percentage. We present an 81-year-old man with stage 3 chronic obstructive pulmonary disease and a history of aortic aneurysm repair. The computed tomography scans indicated thickening and irregularity of the bladder wall, with left external iliac lymph node metastasis. His diagnosis was bladder cancer, and the clinical stage was evaluated as T3N1M0. Transurethral resection of the bladder tumor was performed, and the pathological specimen showed that the tumor was composed of undifferentiated malignant cells with sheets and nests arranged in a syncytial pattern, as well as an urothelial carcinoma lesion. A prominent lymphoid reaction accompanied the tumor. The pathological diagnosis was focal-type lymphoepithelioma-like carcinoma containing a component of urothelial carcinoma G3>G2. His general condition was such that he could not tolerate radical cystectomy or systemic chemotherapy. External beam radiotherapy (total 60 Gy) was given to the bladder, including the lymph node metastatic lesion. No cancer recurrence was detected by regular follow-up computed tomography and cystoscopy. He eventually died of other causes 48 months later. Although treatment for focal lymphoepithelioma-like carcinoma generally requires multifocal therapies, in the present case, the bladder became tumor free. We also summarize previously reported lymphoepithelioma-like carcinoma cases treated with radiotherapy.

Cutaneous metastasis of micropapillary urothelial carcinoma

A 59-year-old man presented with persistent skin rash found to be cutaneous metastasis from micropapillary urothelial carcinoma status post right radical nephroureterectomy and adjuvant chemotherapy. The skin metastasis appeared 2 months after postchemotherapy imaging demonstrated complete radiographic response. Cutaneous metastases from primary genitourinary malignancies are very rare clinical entities associated with poor prognosis. Cutaneous metastases do not have distinctive gross appearance and are often misdiagnosed as common dermatologic disorders. It is imperative that urologists have high index of suspicion for metastasis in patients with persistent skin rash in the setting of advanced genitourinary malignancies.

Mapping of actionable mutations to histological subtype domains in lung adenocarcinoma: implications for precision medicine

Precision medicine depends on the accurate identification of actionable mutations in a tumor sample. It is unknown how heterogeneous the distribution of such mutations can be in a tumor. Morphological (i.e. histopathological) heterogeneity is well described in lung adenocarcinoma and has been specifically recognized in the most recent official clinico-pathological classification. The most predominant subtype present is now used to classify each lung adenocarcinoma. No molecular profile exists to explain the intratumoral differences in lung adenocarcinoma morphology, despite the consistently observed association between specific predominant subtypes and poorer survival. Given a recent proposal stratifying lung adenocarcinoma into subtypes of differing metastatic potential, we questioned the assumption that major mutations are present uniformly throughout tumors; especially those showing discrete different subtypes.

We selected formalin-fixed paraffin embedded lung adenocarcinoma specimens that showed discrete areas of different subtypes, extracted subtype DNA samples from those areas and screened for mutations in hotspot regions of the EGFR, KRAS and BRAF genes using high resolution melting. Sanger sequencing was used to confirm all identified mutations. Chromogenic in situ hybridization (CISH) was used to identify mutant allele specific imbalances in tumors with EGFR mutations.

Interestingly, we found that KRAS and BRAF mutations could be confined to morphological domains of higher grade. On the other hand, EGFR mutations were found through all histological subtypes in each tumor consistent with the driver status of this mutation.

Intratumoral heterogeneity has major implications for tumorigenesis, chemoresistance and the role of histopathology in molecular screening for precision medicine. This study not only confirms that intratumoral mutational heterogeneity does occur, but also that it is associated with morphologically distinct regions in some tumors. From a practical perspective, small biopsies may not adequately represent a tumor's full mutational profile, particularly for later arising but prognostically important mutations such as those in the KRAS and BRAF genes.

Gastric intramucosal adenocarcinoma with an invasive micropapillary carcinoma component

A 70-year-old woman was referred to our hospital because of early gastric cancer (lesser curvature of the antrum, 0-IIc, tub1, 15 mm) and underwent endoscopic submucosal dissection. Microscopically, the lesion was found to be confined to the mucosa, and predominantly composed of well-differentiated tubular adenocarcinoma with a micropapillary component. On immunohistochemical examination, the characteristic "inside-out pattern" of the micropapillary component was observed; thus, we diagnosed the lesion as gastric cancer with a micropapillary component. Invasive micropapillary carcinoma is a rare subtype of gastric carcinoma, and, to our knowledge, this is the first case of invasive micropapillary carcinoma of the stomach confined to the mucosa.

Clinical outcomes of cT1 micropapillary bladder cancer

PURPOSE

While many urologists recommend radical cystectomy for micropapillary bladder cancer invading the lamina propria (cT1), contradictory small reports exist on the efficacy of conservative management with intravesical bacillus Calmette-Guérin for this disease. We report our updated experience in what to our knowledge is the largest series of patients with cT1 micropapillary bladder cancer.

MATERIALS AND METHODS

An institutional review board approved review of our cancer database identified 283 patients with micropapillary bladder cancer, including 72 staged with cT1N0M0 disease at diagnosis and initiation of therapy. Survival analysis was performed using the Kaplan-Meier estimator and compared using the log rank test.

RESULTS

In this cohort of 72 patients 40 received primary intravesical bacillus Calmette-Guérin and 26 underwent up-front radical cystectomy. Of patients who received bacillus Calmette-Guérin 75%, 45% and 35% experienced disease recurrence, progression and lymph node metastasis, respectively. Patients treated with up-front cystectomy had improved survival compared to patients treated with primary bacillus Calmette-Guérin (5-year disease specific survival 100% vs 60% p = 0.006) and patients who underwent delayed cystectomy after recurrence (5-year disease specific survival 62%, p = 0.015). Prognosis was especially poor in patients who waited for progression before undergoing radical cystectomy with an estimated 5-year disease specific survival of only 24% and a median survival of 35 months. In patients treated with up-front cystectomy pathological up-staging was found in 27%, including 20% with lymph node metastasis.

CONCLUSIONS

While certain patients with T1 micropapillary bladder cancer may respond to intravesical bacillus Calmette-Guérin, survival is improved in those who undergo early radical cystectomy. Further molecular studies are needed to identify subsets of patients in whom the bladder can be safely spared.

Micropapillary pattern and poorly differentiated clusters represent the same biological phenomenon in colorectal cancer: a proposal for a change in terminology

OBJECTIVES

Colorectal carcinomas (CRCs) with a micropapillary pattern and those showing high counts of poorly differentiated clusters (PDCs) are characterized by a higher probability to develop nodal metastases and have a worse prognosis. In light of the morphologic similarity to the micropapillary component, we aimed to verify whether PDCs also display an inverted secretory pattern.

METHODS

The immunohistochemical expression of MUC1 and E-cadherin was assessed in a cohort of CRCs with PDCs and compared with that observed in CRCs without PDCs.

RESULTS

PDCs in our cases always displayed an inverted MUC1 pattern. In addition, we found abnormal (lost or cytoplasmic) expression of E-cadherin in PDCs.

CONCLUSIONS

The altered expression of MUC1 and E-cadherin may account for the aggressive behavior and higher metastatic potential of CRCs with high PDC counts and indicate an epithelial-mesenchymal transition. Our findings suggest that regardless of the morphologic aspect, PDCs and the micropapillary component may reflect the same biological phenomenon in CRCs. Thus, we wonder whether the micropapillary areas should be considered a variant of CRCs or more objectively counted as PDCs to predict prognosis. We also believe that the term PDC better describes the biological phenomena underlying this peculiar morphologic aspect in comparison with the misnomer micropapillary.

Micropapillary bladder cancer: current treatment patterns and review of the literature

OBJECTIVES

No guidelines exist for the management of micropapillary bladder cancer (MPBC) and most reports of this variant of urothelial carcinoma are case series comprising small numbers of patients. We sought to determine current practice patterns for MPBC using a survey sent to the Society of Urologic Oncology (SUO) and to present those results in the setting of a comprehensive review of the existing literature.

MATERIALS AND METHODS

A survey developed by the Translational Science Working Group of the Bladder Cancer Advocacy Network-sponsored Think Tank meeting was distributed to members of the SUO. The results from 118 respondents were analyzed and presented with a literature review.

RESULTS

Most survey respondents were urologists, with 80% considering bladder cancer their primary area of interest. Although 78% of the respondents reported a dedicated genitourinary pathologist at their institution, there were discrepant opinions on how a pathologic diagnosis of MPBC is determined as well as variability on the proportion of MPBC that is clinically significant. Among them, 78% treat MPBC differently than conventional urothelial carcinoma, with 81% reporting that they would treat cT1 MPBC with upfront radical cystectomy. However, the respondents had split opinions regarding the sensitivity of MPBC to cisplatin-based chemotherapy, which affected utilization of neoadjuvant chemotherapy in muscle-invasive disease.

CONCLUSIONS

The management of MPBC is diverse among members of the SUO. Although most favors early cystectomy for cT1 MPBC, there is no consensus on the use of neoadjuvant chemotherapy for muscle-invasive MPBC.

Hobnail variant of papillary thyroid carcinoma: an institutional case series and molecular profile

BACKGROUND

Papillary thyroid carcinoma (PTC) is increasing in incidence while mortality is unchanged. Identifying patients with higher risk of recurrence and death is essential. Case series identify the hobnail variant of PTC (HVPTC), which is characterized by micropapillary architecture, apocrine features, and loss of cellular polarity. Herein, we describe the clinical course, pathologic features, and mutational profile of patients at our institution with HVPTC.

METHODS

A query into the surgical pathologic database (2009-2012) was performed, and clinicopathologic data were collected on all patients carrying the diagnosis of HVPTC. BRAF(V600E) testing was performed on paraffin-embedded blocks using SNaPshot mutational analysis.

RESULTS

Twelve patients with HVPTC were identified, with an average age of 54.1±18.8 years. Seven patients (63.6%) were AJCC Stage III or IV at presentation. Tumors were large (3.7±2.0 cm), some were multifocal (33.3%), and frequently with extrathyroidal extension (58.3%), lymphovascular invasion (41.7%), and lymph node metastasis (75%). Forty percent of the patients had concomitant tall cell features (TCF), and two had small foci of undifferentiated (anaplastic) thyroid carcinoma (ATC). Eighty percent of tumors undergoing mutational analysis had the BRAF(V600E) mutation, and the remaining 20% harbored a RET/PTC1 gene rearrangement. No other known thyroid cancer mutations were identified on SNaPshot analysis. At median follow-up of 26 months, four patients had recurrent or persistent disease, one of whom died from the disease one year after surgery.

CONCLUSIONS

The hobnail variant of PTC has an aggressive behavior, with a high incidence of infiltrative tumors and metastatic disease. Strikingly, all tumors in our series harbored a PTC-associated genetic abnormality, either a BRAF(V600E) mutation (80%) or a RET/PTC1 rearrangement (20%). This histologic variant warrants further study, and patients with this diagnosis should be observed closely for recurrence.

Cytological features of pure micropapillary carcinoma of various organs: A report of eight cases

Micropapillary carcinoma (MPC) is a rare aggressive tumor, which generally accompanies the primary carcinoma of the organ of its origin, while the pure form is extremely uncommon. Angiolymphatic involvement is widespread and a considerable proportion of the cases present with metastases. The current study presents eight pure MPC cases arising from the breast (n=3), urinary bladder (n=3), parotid gland (n=1) and lung (n=1, presenting with pericardial effusion), with the cytological findings. The eight patients included three female and five male cases aged between 48 and 74 years. The most common cytological findings were three-dimensional aggregates, cell clusters with angulated or scalloped borders, single cells with a columnar configuration and eccentric nuclei, and high-grade nuclear features. Histopathological sections showed accompanying in situ ductal carcinoma in the cases of MPC arising in the parotid gland and breast (n=3), and one case in the bladder exhibited only in situ MPC. The average follow-up period was 20 months (range, 6–54 months) and, during this period, three patients succumbed to the disease. At present, four patients are alive with disease and one patient is alive and disease-free. In conclusion, cytology is an important tool for the diagnosis and management of MPC.

The utility of p63, p40, and GATA-binding protein 3 immunohistochemistry in diagnosing micropapillary urothelial carcinoma

Micropapillary urothelial carcinoma (MPUC) is an uncommon variant of urothelial carcinoma (UC) with an aggressive clinical course. There have been limited studies on the UC markers GATA-binding protein 3 (GATA3), p63, and p40 in MPUC. Our study investigated the immunoreactivity of these 3 markers in MPUC compared with conventional UC of different grades and stages. Immunohistochemistry was performed on 62 cases of high-grade urothelial carcinoma (HGUC), 16 low-grade urothelial carcinoma (LGUC), and 20 MPUC. p63 expression was strong and diffuse in all LGUC, significantly decreased in high stage and HGUC, and virtually absent in MPUC. p40 expression was decreased in HGUC and markedly decreased in MPUC relative to LGUC. These results suggest that loss of p63 expression in a UC appears to be associated with adverse features--including cases with micropapillary differentiation. Decreased GATA3 expression was seen frequently in high-grade and high-pathologic stage (≥pT2) tumors but was retained in MPUC cases. The findings of retained GATA3 expression in MPUC, which often shows a loss of expression of other urothelial markers such as p63, may be helpful for determining the origin of micropapillary carcinoma of unknown primary. Compared with the traditional markers p63 and p40, GATA3 is the most sensitive marker of conventional UC and MPUC.

Outcome of patients with micropapillary urothelial carcinoma following radical cystectomy: ERBB2 (HER2) amplification identifies patients with poor outcome

Micropapillary urothelial carcinoma exhibits amplification of the human epidermal growth factor receptor, ERBB2(HER2), and overexpression of the ERBB2 protein product. The clinical significance of this has yet to be established. The objective of this study was to examine ERBB2 amplification and protein expression in micropapillary urothelial carcinoma and stage-matched typical urothelial carcinoma treated by radical cystectomy to assess the frequency of amplification and protein expression, and to determine the association with cancer-specific survival. Pathologic material and data from patients undergoing cystectomy at Mayo Clinic between 1980 and 2008 were reviewed. ERBB2 amplification by fluorescence in situ hybridization (FISH) and protein expression by immunohistochemistry were assessed. Univariate and multivariate Cox proportional hazards regression models were used to evaluate for associations of ERBB2 amplification and protein expression with survival. ERBB2 amplification was identified in 9 (15%) of 61 micropapillary carcinomas compared with 9 (9%) of 100 urothelial carcinomas. In patients with micropapillary carcinoma, ERBB2 amplification was associated with a nearly threefold increased risk of cancer death. ERBB2 amplification (hazard ratio 4.3; P=0.0008) remained associated with an increased risk of death from bladder cancer among patients with micropapillary urothelial carcinoma on multivariate analysis. The association of cancer-specific survival and ERBB2 amplification was not seen in patients with urothelial carcinoma. ERBB2 immunohistochemistry correlated with ERBB2 amplification but there was no association of ERBB2 protein expression and survival. ERBB2 amplification is more frequent in micropapillary urothelial carcinoma than typical urothelial carcinoma, and patients with micropapillary carcinoma who have ERBB2 amplification have worse cancer-specific survival than those who do not. Identification of ERBB2 amplification in micropapillary carcinoma could provide important prognostic information and possibly provide a role for ERBB2 targeted therapy.

Invasive micropapillary carcinoma: A distinct type of adenocarcinomas in the gastrointestinal tract

Invasive micropapillary carcinoma (IMPC) is a rare histological type of tumor, first described in invasive ductal breast cancer, than in malignancies in other organs such as lungs, urinary bladder, ovaries or salivary glands. Recent literature data shows that this histological lesion has also been found in cancers of the gastrointestinal system. The micropapillary components are clusters of neoplastic cells that closely adhere to each other and are located in distinct empty spaces. Moreover, clusters of neoplastic cells do not have a fibrous-vascular core. The IMPC cells show reverse polarity resulting in typical ‘’inside-out’’ structures that determines secretary properties, disturbs adhesion and conditions grade of malignancy in gastrointestinal (GI) tract. Invasive micropapillary carcinoma in this location is associated with metastases to local lymph nodes and lymphovascular invasion. IMPC can be a prognostic factor for patients with cancers of the stomach, pancreas and with colorectal cancer since it is related with disease-free and overall survival. The purpose of this review is to present the characterization of invasive micropapillary carcinoma in colon, rectum, stomach and others site of GI tract, and to determine the immunohistological indentification of IMPC in those localization.

Pathological characteristics of early to advanced gallbladder carcinoma and extrahepatic cholangiocarcinoma

Biliary tract cancer (cancer of gallbladder and extrahepatic bile duct) is the most common malignancy of the biliary tract, and is considered to be a high-grade malignancy. In this study, we reviewed 293 gallbladder cancers and 102 bile duct cancers for clarifying growth and invasion of the extrahepatic bile duct cancer. Only 10.5% (9/86) of the early gallbladder cancers showed lymphatic invasion, but neither venous invasion nor lymph node metastasis was noted in the early cancers. 70.6% (207/293) of the gallbladder cases were pT2-3 cancers, and frequently showed lymphatic/venous/perineural invasion and/or lymph node metastasis. 12.7% (13/102) of the extrahepatic bile duct cancers were pTis or pT1 cancers, which were categorized as early cancers. Only 15.4% (2/13) of the early cancer showed vascular/perineural invasion and/or lymph node metastasis. The majority (87.3%) of the extrahepatic bile duct cases was pT2-3 cancers, and frequently showed vascular/perineural invasion and/or lymph node metastasis. We also examined intramural invasion patterns; i.e. intramural invasion patterns were defined as infiltrative growth (IG) type, and destructive growth (DG) type. The overall survival rate of the gallbladder cancer patients with the DG type was significantly lower than that of the patients with the IG type, associated with frequent lymphatic/venous invasion and/or lymph node metastasis. Therefore, pathological characteristics are important for clinical manifestation of the gallbladder/extrahepatic bile duct cancers.

Clinical outcome of patients with T1 micropapillary urothelial carcinoma of the bladder

PURPOSE

We report cancer specific outcomes of micropapillary nonmuscle invasive bladder cancer.

MATERIALS AND METHODS

We retrospectively reviewed the records of 36 cases restaged within 3 months of the initial diagnosis of micropapillary nonmuscle invasive bladder cancer. Early radical cystectomy within a 3-month landmark after restaging transurethral bladder tumor resection or conservative treatment with intravesical bacillus Calmette-Guérin, surveillance or deferred radical cystectomy was offered according to surgeon and patient preference. The cumulative incidence of cancer specific mortality and metastasis was estimated using the Kaplan-Meier method. Differences in the cumulative incidence of cancer specific mortality and metastasis between the groups were tested using the log rank test.

RESULTS

Median patient age was 68 years (IQR 63-77). The male-to-female ratio was 3:1. At restaging all patients had cT1 disease or less. Early radical cystectomy was performed in 15 patients (42%) while 21 (58%) underwent conservative treatment. Median followup after landmark in cancer specific survivors was 3.1 years (IQR 1.1-5.9). The 5-year cumulative incidence of cancer specific mortality was 17% in the early radical cystectomy group and 25% in the conservative management group for an absolute difference of 7% (95% CI -26-41, p = 0.8). The 5-year cumulative incidence of metastasis was 21% and 34%, respectively, with an absolute difference of 13% (95% CI -23-49, p = 0.9). The extent of the micropapillary component was not significantly associated with cancer specific mortality (p = 0.4) or metastasis (p = 0.9).

CONCLUSIONS

Using proper selection criteria, including patient and pathological factors, certain patients in whom cT1 micropapillary urothelial carcinoma was managed conservatively did not have significantly worse outcomes than patients treated with early radical cystectomy.

Micropapillary carcinoma of the urinary tract: a cytologic study of urine and fine-needle aspirate samples

OBJECTIVE

Micropapillary carcinoma (MPC) is an aggressive variant of urothelial carcinoma that needs early and specific recognition. In order to determine whether this tumor variant can be recognized with cytology, we evaluated a large cytohistological series.

STUDY DESIGN

It was a retrospective cytohistological correlation study including 20 patients with MPC. Only those cases in which the tumor exhibited >50% of micropapillary growth were selected. Twenty exfoliative urine specimens and four needle aspirates from lymph node metastases were reviewed.

RESULTS

On histology, 14 cases were infiltrative, while 6 were exclusively superficial. Cytology was characterized by numerous small, cohesive groups and single neoplastic cells. Pseudopapillae were present in 17 cases and in 9 they were a relevant finding. Morules were present in 15 cases. Isolated microacini were seen in 14 cases. Infiltrative tumors showed more neoplastic groups. Cellular atypia was prominent in 17 cases. In 15 cases, a cytologic diagnosis of urothelial carcinoma was made. One case was diagnosed as adenocarcinoma. The remaining 4 cases were considered suspicious of malignancy.

CONCLUSIONS

The peculiar morphology of MPC of the urinary tract is partially reflected on cytology, allowing in some cases a specific recognition. This is important since the aggressive behavior of this neoplasm needs rapid management and treatment.

Controversial issues and optimal management of stage T1G3 bladder cancer

The management of T1G3 bladder cancer is controversial. Diagnostic methods, such as bladder mapping or second-look transurethral resection are recommended to assess risk. Bacillus Calmette-Guérin intravesical therapy with a maintenance regimen is recommended for solitary T1G3 tumors. The timing of radical cystectomy for these patients is controversial, but early recurrence during intravesical therapy is an indication for radical cystectomy. Multifocal disease, concomitant carcinoma in situ and disease in the prostatic urethra and bladder neck also suggest aggressive disease and cystectomy should be considered in these patients.

Micropapillary pattern at the invasive front and its association with unresectable colorectal carcinomas

Unresectable colorectal carcinomas (CRCs) as considered incurable even if the primary tumors and the metastatic ones can undergo resection are correlated with poor prognosis. We evaluated the association between micropapillary pattern at the invasive front and unresectable CRCs. Thirty-four out of 264 (12.9%) CRC patients with stages III and IV were unresectable cases. The patients with unresectable CRCs had significantly worse survival than those with resectable CRCs (P < 0.001). Micropapillary pattern was evident in 12 (4.5%) out of 264 cases. This pattern was observed in 6 of 34 (17.6%) unresectable CRCs and in 6 of 230 (2.6%) resectable cases (P = 0.002). Unresectable CRCs revealed more frequently deeper invasion (odds ratio (OR), 1.175; 95% confidence interval (CI), 1.113-1.241), lymph node metastasis (OR, 2.356; 95% CI, 1.132-4.905), and presence of micropapillary pattern at the invasive front (OR, 8.000; 95% CI, 2.415-26.504) as compared to resectable cases. By multivariable logistic regression analysis, only micropapillary pattern was shown to be an independent predictor of unresectable CRCs (OR, 9.451; 95% CI, 2.468-36.196; P < 0.001). In conclusion, micropapillary pattern at the invasive front is associated with unresectable CRCs, and detection of it could help identify unresectable CRC cases.

Napsin A expression in anaplastic, poorly differentiated, and micropapillary pattern thyroid carcinomas

Napsin A is a sensitive and specific marker for pulmonary adenocarcinoma versus squamous cell carcinoma. However, studies have shown that napsin A is also positive in approximately 5% of papillary thyroid carcinomas. The prevalence of napsin A in more aggressive types of thyroid carcinoma is unknown. Napsin A positivity in metastatic thyroid carcinoma, especially in conjunction with thyroid transcription factor-1 (TTF-1), could be misdiagnosed as lung adenocarcinoma. We investigated napsin A, TTF-1, and PAX8 expression in 26 anaplastic, 16 poorly differentiated, and 2 micropapillary pattern thyroid carcinomas. A focal micropapillary component was also present in 3 poorly differentiated and 3 anaplastic thyroid carcinomas. Four of 26 (15%) anaplastic, 2/16 (13%) poorly differentiated, and 2/2 (100%) micropapillary pattern thyroid carcinomas were napsin A positive. Three of the 6 cases (50%) with a focal micropapillary component were napsin A positive (1 of these 3 cases was positive only in the micropapillary component). All napsin A-positive cases were also positive for TTF-1, and all but 1 micropapillary pattern carcinoma were also PAX8 positive. In 1 case, napsin A was positive in the micropapillary component, but PAX8 was only positive in the adjacent poorly differentiated carcinoma. In summary, a minority of anaplastic and poorly differentiated thyroid carcinomas are napsin A positive. More importantly, napsin A expression is more common in carcinomas with a micropapillary component, a pattern shared in common with some lung adenocarcinomas. PAX8 may be diagnostically useful to distinguish these napsin A-positive thyroid carcinomas from lung adenocarcinomas, which are PAX8 negative.

Cytological findings of the micropapillary variant of urothelial carcinoma: a comparison with typical high-grade urothelial carcinoma

Background

Micropapillary 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).

Methods

The 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.

Results

Compared 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.

Conclusions

The 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.

Clinical significance of micropapillary urothelial carcinoma of the upper urinary tract

BACKGROUND

The aim of this study was to improve understanding of the characteristics of micropapillary urothelial carcinoma (MPUC) in the renal pelvis and ureter, and to compare oncological outcomes between MPUC and non-MPUC.

METHODS

From September 1994 to October 2010, 418 patients underwent nephroureterectomy with bladder excision due to presumed urothelial carcinoma. Pathological review of all specimens was done by one uropathologist. Perioperative data from these patients were reviewed retrospectively. Patients were divided into MPUC and non-MPUC groups. Oncological outcomes were compared between the two groups via progression-free survival (PFS) and cancer-specific survival (CSS) rates.

RESULTS

A total of 386 patients were included in the study. Of these, seven patients (1.81%) had MPUC. The median follow-up duration was 39.0 months (IQR range 21.1-70.6). All MPUC patients were men and had lymphovascular invasion, and six patients (85.7%) had grade III and T3 disease. On univariable analysis, MPUC showed significantly worse prognosis with regard to disease progression (p<0.001). In the subgroup analysis confined to T3 or T4 disease, MPUC showed worse prognosis than non-MPUC in terms of PFS and CSS, respectively (p<0.05). In the multivariable model, MPUC still remained a statistically significant independent predictor for PFS (HR (95% CI)=3.85 (1.59-9.32), p=0.003). MPUC was associated with poorer CSS than non-MPUC (p<0.001).

CONCLUSIONS

We have observed that upper tract MPUC is associated with poor oncological outcomes in terms of PFS and CSS. MPUC was an independent prognostic factor for PFS in multivariable analysis.

Colorectal micropapillary carcinomas are associated with poor prognosis and enriched in markers of stem cells

Colorectal micropapillary carcinoma has recently been reported as an aggressive variant of adenocarcinoma with a high incidence of lymph node metastasis, but has not been well investigated in terms of survival analysis. This study analyzed the clinicopathological characteristics, including survival data, of the patients with micropapillary carcinoma. We hypothesized that the aggressive features of micropapillary carcinoma might be related to the presence of more tumor cells with stem cell phenotype in colorectal cancer. Fifty-five (10%) micropapillary carcinoma cases were identified among 561 cases of colorectal cancer. We compared the clinicopathological characteristics, including survival data and immunohistochemical profiles of stem cell markers (SOX2, NOTCH3, CD44v6, CD166, ALDH1) of micropapillary carcinomas with those of randomly selected 112 conventional adenocarcinomas lacking micropapillary carcinoma components (non-micropapillary carcinoma) in the colorectum. To exclude the possibility of dilution of control group by patients with microsatellite instability-high carcinomas, we divided non-micropapillary carcinomas into microsatellite instability-high carcinoma and microsatellite stable tumors. Micropapillary carcinomas were characterized by more frequent lymphovascular invasion (P<0.0001) and lymph node metastasis (P<0.0001), higher pathological T and tumor node metastasis stages (P=0.047 and P=0.001), and more frequent SOX2 (P=0.038) and NOTCH3 expressions (P=0.005). Overall 5-year survival rate for patients with micropapillary carcinoma (37%) was significantly lower than for microsatellite instability-high carcinoma and microsatellite stable carcinoma patients (92 and 72%, P<0.0001). The presence of the micropapillary carcinoma component was shown to be associated with a significantly worse survival rate in univariate (P<0.0001) and multivariate (P=0.003, Cox hazard ratio 2.402) analyses. In conclusion, recognition of the micropapillary carcinoma component in colonic adenocarcinoma is very important, because the micropapillary carcinoma has been associated with a significantly worse prognosis. We also found a higher expression rate of cancer stem cell markers in micropapillary carcinomas, suggesting their potential contribution to the survival disadvantage of micropapillary carcinoma.

Micropapillary variant of embryonal carcinoma: clinicopathological correlation and histochemical study

Micropapillary pattern of growth (MPG) of carcinoma is a unique morphologic pattern. It is uncommon but a predictor of poor outcome. MPG has not been described in any germ cell tumor, most notably embryonal carcinoma, which may have papillary configuration. In this study, we reviewed 25 primary testicular germ cell tumors (pure or mixed) containing embryonal carcinoma and 2 lymph node metastases with embryonal carcinoma. Five of the 25 primary cases demonstrated MPG. With available clinical information, 3/3 (100%) cases with MPG and 5/12 (42%) cases without MPG showed evidence of metastases. The 2 lymph node metastases contained predominantly MPG. At metastasis, the median tumor size in primary tumors with MPG was significantly smaller than in those without MPG. Reticulum staining was negative in the regions of MPG and positive for other coexisting non-micropapillary growth patterns in all the 6 embryonal carcinomas. In conclusion, we described MPG in embryonal carcinoma. Although limited by the number of cases, our clinicopathological correlation results raised the possible association of the presence of MPG to the high-rate metastasis of embryonal carcinoma, similar to that seen in other carcinomas with MPG. It is therefore of importance to document this variant growth pattern if present in embryonal carcinoma. We also demonstrated that reticulum is a useful negative marker for identification of MPG.

[Metastatic micropapillary variant of urothelial carcinoma of the urinary bladder responding to gemcitabine and cisplatin chemotherapy]

A 69-year-old man was admitted to our hospital with a chief complaint of lymphatic edema of left arm. He had a past history of transurethral resection of the bladder tumor 5 years ago, and pathological diagnosis was urothelial carcinoma with micropapillary variant, G3 = G2, pT1. CT scan revealed bladder tumor with invasion of the rectum, and multiple lymph nodes swelling in the axilla, retroperitoneum and pelvis (cT4bN3M1). The patient underwent biopsies of the bladder wall and the left axillary lymph nodes, and pathologic examination revealed micropapillary carcinoma. Five courses of gemcitabine plus cisplatin (GC therapy) were perfomed, and bladder tumor and lymph node metastases reduced remarkably, with serum CA19-9 level decreasing from 172,000 U/ml to 106 U/ml. However, the patient died from recurrence 23 months after the start of GC therapy.