High-grade urothelial carcinoma of the renal pelvis: clinicopathologic study of 108 cases with emphasis on unusual morphologic variants

Sarcomatoid and Rhabdoid Renal Cell Carcinoma: Clinical, Pathologic, and Molecular Genetic Features

Renal cell carcinoma (RCC) with sarcomatoid and rhabdoid morphologies has an aggressive biological behavior and a typically poor prognosis. The current 2022 WHO classification of renal tumors does not include them as distinct histologic entities but rather as transformational changes that may arise in a background of various distinct histologic types of RCC. The sarcomatoid component shows malignant spindle cells that may grow as intersecting fascicles, which is reminiscent of pleomorphic undifferentiated sarcoma. The rhabdoid cells are epithelioid cells with eccentrically located vesicular nuclei with prominent nucleoli and large intracytoplasmic eosinophilic inclusions. Studies have shown that RCCs with sarcomatoid and rhabdoid differentiation have distinctive molecular features. Sarcomatoid RCC harbors shared genomic alterations in carcinomatous and rhabdoid components, but also enrichment of specific genomic alterations in the sarcomatoid element, suggesting molecular pathways for development of sarcomatoid growth from a common clonal ancestor. Rhabdoid differentiation also arises through clonal evolution although less is known of specific genomic alterations in rhabdoid cells. Historically, treatment has lacked efficacy, although recently immunotherapy with PD-1/PD-L1/CTLA-4 inhibitors has produced significant clinical responses. Reporting of sarcomatoid and rhabdoid features in renal cell carcinoma is required by the College of American Pathologists and the International Collaboration on Cancer Reporting. This manuscript reviews the clinical, pathologic, and molecular features of sarcomatoid RCC and rhabdoid RCC with emphasis on the morphologic features of these tumors, significance of diagnostic recognition, the molecular mechanisms of tumorigenesis and differentiation along sarcomatoid and rhabdoid lines, and advances in treatment, particularly immunotherapy.

Development and validation of a clinical and ultrasound features-based nomogram for preoperative differentiation of renal urothelial carcinoma and central renal cell carcinoma

PURPOSE

This study aimed to develop and validate an ultrasound (US)-based nomogram for the preoperative differentiation of renal urothelial carcinoma (rUC) from central renal cell carcinoma (c-RCC).

METHODS

Clinical data and US images of 655 patients with 655 histologically confirmed malignant renal tumors (521 c-RCCs and 134 rUCs) were collected and divided into training (n = 455) and validation (n = 200) cohorts according to examination dates. Conventional US and contrast-enhanced US (CEUS) tumor features were analyzed to determine those that could discriminate rUC from c-RCC. Least absolute shrinkage and selection operator regression was applied to screen clinical and US features for the differentiation of rUC from c-RCC. Using multivariate logistic regression analysis, a diagnostic model of rUC was constructed and visualized as a nomogram. The diagnostic model's performance was assessed in the training and validation cohorts by calculating the area under the receiver operating characteristic curve (AUC) and calibration plot. Decision curve analysis (DCA) was used to assess the clinical usefulness of the US-based nomogram.

RESULTS

Seven features of both clinical features and ultrasound imaging were selected to build the diagnostic model. The nomogram achieved favorable discrimination in the training (AUC = 0.996, 95% CI: 0.993-0.999) and validation (AUC = 0.995, 95% CI: 0.974, 1.000) cohorts, and good calibration (Brier scores: 0.019 and 0.016, respectively). DCA demonstrated the clinical usefulness of the US-based nomogram.

CONCLUSION

A noninvasive clinical and US-based nomogram combining conventional US and CEUS features possesses good predictive value for differentiating rUC from c-RCC.

Impact of Variant Histology on Oncological Outcomes in Upper Tract Urothelial Carcinoma: Results From the ROBUUST Collaborative Group

INTRODUCTION

Oncologic implications of variant histology (VH) have been extensively studied in bladder cancer; however, further investigation is needed in upper tract urothelial carcinoma (UTUC). Our study aims to evaluate the impact of VH on oncological outcomes in UTUC patients treated with radical nephroureterectomy (RNU).

METHODS

A retrospective analysis was performed on patients who underwent a robotic or laparoscopic RNU for UTUC using the ROBUUST database, a multi-institutional collaborative including 17 centers worldwide. Logistic regression was used to assess the effect of VH on urothelial recurrence (bladder, contralateral upper tract), metastasis, and survival following RNU.

RESULTS

A total of 687 patients were included in this study. Median (IQR) age was 71 (64-78) years and 470 (68%) had organ confined disease. VH was present in 70 (10.2%) patients. In a median follow-up of 16 months, the incidence of urothelial recurrence, metastasis, and mortality was 26.8%, 15.3%, and 11.8%, respectively. VH was associated with increased risk of metastasis (HR 4.3, P <.0001) and death (HR 2.0, P =.046). In multivariable analysis, VH was noted to be an independent risk factor for metastasis (HR 1.8, P =.03) but not for urothelial recurrence (HR 0.99, P =.97) or death (HR 1.4, P =.2).

CONCLUSION

Variant histology can be found in 10% of patients with UTUC and is an independent risk factor for metastasis following RNU. Overall survival rates and the risk of urothelial recurrence in the bladder or contralateral kidney are not affected by the presence of VH.

Primary Squamous Cell Carcinoma of the Renal Pelvis: A Rare Complication of Xanthogranulomatous Pyelonephritis

Xanthogranulomatous pyelonephritis is a rare disease resulting from chronic inflammation and infection of the renal parenchyma. It usually arises as a consequence of obstructive chronic pyelonephritis. Primary squamous cell carcinoma of the renal pelvis is a distinct pathology, very rare in clinical practice, with a well-established association with xanthogranulomatous pyelonephritis. The authors present the case of a 57-year-old woman with chronic pyelonephritis containing xanthogranulomatous features. Subsequent workup revealed a concomitant, unsuspected, primary squamous cell carcinoma of the renal pelvis. With this case, the authors intend to emphasize and reinforce the need to be alert to an uncommon association between two rare diseases due to its diagnostic, therapeutic, and prognostic implications.

European Association of Urology Guidelines on Upper Urinary Tract Urothelial Carcinoma: 2023 Update

CONTEXT

The European Association of Urology (EAU) guidelines panel on upper urinary tract urothelial carcinoma (UTUC) has updated the guidelines to aid clinicians in evidence-based management of UTUC.

OBJECTIVE

To provide an overview of the EAU guidelines on UTUC as an aid to clinicians.

EVIDENCE ACQUISITION

The recommendations provided in these guidelines are based on a review of the literature via a systematic search of the PubMed, Ovid, EMBASE, and Cochrane databases. Data were searched using the following keywords: urinary tract cancer, urothelial carcinomas, renal pelvis, ureter, bladder cancer, chemotherapy, ureteroscopy, nephroureterectomy, neoplasm, (neo)adjuvant treatment, instillation, recurrence, risk factors, metastatic, immunotherapy, and survival. The results were assessed by a panel of experts.

EVIDENCE SYNTHESIS

Even though data are accruing, for many areas there is still insufficient high-level evidence to provide strong recommendations. Patient stratification on the basis of histology and clinical examination (including imaging) and assessment of patients at risk of Lynch syndrome will aid management. Kidney-sparing management should be offered as a primary treatment option to patients with low-risk UTUC and two functional kidneys. In particular, for patients with high-risk or metastatic UTUC, new treatment options have become available. In high-risk UTUC, platinum-based chemotherapy after radical nephroureterectomy, and adjuvant nivolumab for unfit or patients who decline chemotherapy, are options. For metastatic disease, gemcitabine/carboplatin chemotherapy is recommended as first-line treatment for cisplatin-ineligible patients. Patients with PD-1/PD-L1-positive tumours should be offered a checkpoint inhibitor (pembrolizumab or atezolizumab).

CONCLUSIONS

These guidelines contain information on the management of individual patients according to the current best evidence. Urologists should take into account the specific clinical characteristics of each patient when determining the optimal treatment regimen according to the risk stratification of these tumours.

PATIENT SUMMARY

Cancer of the upper urinary tract is rare, but because 60% of these tumours are invasive at diagnosis, timely and appropriate diagnosis is most important. A number of known risk factors exist.

Renal Oncocytoma and Pelvic Urothelial Carcinoma in a Nephrectomy Specimen of a 72-Year-Old Patient

We present the case of a 72-year-old gentleman who presented with a left renal mass. His Computerized Tomography Angiogram showed an 11.8 x 11.3 cm mass involving the upper pole of the left kidney. The mass showed a central stellate scar. There was no locoregional lymphadenopathy. His radical nephrectomy specimen was received in our lab. Sectioning showed a large tumor in the upper pole with a central stellate scar. Microscopically, it showed sheets and nests of round cells with eosinophilic cytoplasm and round nuclei. It was positive for CD117 and negative for CK7. The sections from the renal pelvis showed a urothelial carcinoma arising from the urothelial lining and infiltrating the muscular wall of the renal pelvis. This tumor was positive for CK7 and GATA3. In this case report, we present a rare collision tumor of renal oncocytoma and pelvic urothelial carcinoma.

Mutations in a High-Grade Micropapillary Urothelial Carcinoma of the Renal Pelvis: A Case Report

Micropapillary urothelial carcinoma (MPUC) of the renal pelvis is an upper tract urothelial carcinoma originating in the renal pelvis region. Few genetic studies are available, and the mechanism of pathogenesis of genetically driven models is unclear. We report a case of genomic alterations in MPUC of the renal pelvis and compare the results with existing literature. DNA was extracted, followed by the next-generation sequencing of 351 oncogenes and tumor suppressor genes. Targeted gene sequencing analysis revealed somatic variants in ERBB2, KMT2C, FOXA1, and germline variants in CDKN1B, ELF3, TP53, and RB1 genes. The present case study sheds light on recognizing genetic variants in high-grade MPUC of the renal pelvis. Understanding molecular mechanisms helps with better prognostication and development of more effective therapeutics and treatment.

Analysis of genetic profiling, pathomics signature, and prognostic features of primary lymphoepithelioma‐like carcinoma of the renal pelvis

The genetic features of primary lymphoepithelioma‐like carcinoma (LELC) of the upper urinary tract have not been systematically explored. In this study, tumor mutation profiling was performed using whole‐genome sequencing in two patients with LELC of the renal pelvis. Novel candidate variants relevant to known disease genes were selected using rare‐variant burden analysis. Subsequently, a population‐based study was performed using the Surveillance, Epidemiology, and End Results (SEER), PubMed, MEDLINE, Embase, and Scopus databases to explore clinical features and prognostic risk factors. Immunohistochemical analysis revealed seven positive cytokeratin‐associated markers in tumor cells and five positive lymphocyte‐associated markers in and around the tumor area. Sub‐sequently, we identified KDM6A as the susceptibility gene and LEPR as the driver gene by Sanger sequencing in case 2 of LELC of the renal pelvis. Three mutation sites of the existing targeted drugs were screened: CA9, a therapeutic target for zonisamide; ARVCF, a therapeutic target for bupropion; and PLOD3, a therapeutic target for vitamin C. In a population‐based study, patients with primary LELC of the upper urinary tract had clinical outcomes similar to those of patients with primary upper urinary tract urothelial carcinoma (UUT‐UC) before and after propensity score matching at 1 : 5. Focal subtype was an independent prognostic factor for the overall survival of patients with LELC of the upper urinary tract. The carcinogenesis of primary LELC may be due to different genetic variations, including single‐nucleotide variants, insertion and deletions, structural variations, and repeat regions, which may provide the basis for clinical diagnosis and treatment. The prognosis of LELC in the upper urinary tract is similar to that of UUT‐UC. We suggest that the focal subtype can serve as a prognostic factor for LELC of the upper urinary tract; however, further studies are required to confirm this.

Impact of Pathology Review in Adverse Histological Characteristics and pT Stages of Upper Tract Urothelial Cancer in a Multicenter Study

Purpose

Pathology reviews for upper urinary tract cancer (UTUC) remained scarce in the literature. Here, we reported the interobserver variation among the review and local pathologies of featured histologic characteristics for UTUC.

Methods

Patients who underwent definitive surgical treatments for UTUC were retrospectively reviewed for eligibility of pathology review. In the Taiwan UTUC Collaboration cohort, 212 cases were reviewed, of which 154 cases were eligible for pathology review. Agreement between original pathology and review pathology was measured by the total percentage of agreement and by simple kappa statistics. The prognostic impact was analyzed by the Cox regression model with the estimation of hazard ratios (HR) and 95% confidence intervals.

Results

There were 80 women and 74 men enrolled in this study, and the median age at treatment was 71.7 years. The agreement is moderate agreement for surgical margin status (87.7%; κ = 0.61), tumor grade (82.5%; κ = 0.43), tumor invasiveness (76.6%; κ = 0.45), lymphovascular invasion (70.8%; κ = 0.42) and T stage (67.5%; κ = 0.52). The interobserver agreements for perineural invasion and variant histology identification were slight. Kaplan–Meier analysis for disease-free survival revealed comparable results in local and review pathology for localized (Tis, Ta, T1–2) or advanced T stage (T3–4).

Conclusions

Pathology review of UTUC had minimal impact on clinical practice based on current available disease treatment guidelines. However, significant interobserver variations were observed in featured adverse histopathological characters.

Squamous cell carcinoma of the renal pelvis in a patient with long-term spinal cord injury-a case report

INTRODUCTION

For individuals with spinal cord injury/disease (SCI/D) the risk of developing a stone in the upper urinary tract is up to six times higher than in the able-bodied population. Upper urinary tract carcinomas, in general, are rare and account for only 5-10% of all urinary tract carcinomas. It is believed that chronic upper urinary tract irritation caused by e.g., kidney stones or recurrent upper urinary tract infections may be associated with an increased risk of renal squamous cell carcinoma (RSCC).

CASE PRESENTATION

We report on a 64-year-old male who suffered a spinal cord injury in 1981 resulting in a complete sensory and motor impairment below T6, AIS A. Recurrent left-sided kidney stone disease had to be treated repeatedly from 1984 onwards. Despite repeated surgical attempts, it was ultimately not possible to achieve stone clearance in the long term. Within the concept of life-long surveillance of SCI/D, the patient was examined regularly, including ultrasound examinations of the kidneys. Six months after the last control examination, the patient was admitted to our hospital with a locally advanced tumor of the left kidney, so that only the option of palliative treatment remained. Histologically an RSCC was found.

DISCUSSION

As people with SCI/D have a higher risk of developing kidney stones, it is of utmost importance to check regularly for stone disease and, if necessary, treat with the aim of long-term stone clearance in order to protect renal function and to avert potentially malignant changes at an early stage.

Challenging Visualization of Sentinel Lymph Nodes in Upper Urinary Tract Urothelial Carcinoma

Purpose: The purpose of this study was to assess the possibility of detecting sentinel lymph nodes (SLNs) and to perform analysis of lymphatic outflow in patients with suspicion of upper tract urothelial carcinoma (UTUC) with the use of a radioisotope-based technique. Methods: During 2018–2021, a prospective study was conducted on 19 patients with the suspicion of UTUC and for whom diagnostic ureterorenoscopy (URS) was planned. Technetium-99m (^99mTc) nanocolloid radioactive tracer injection and a tumor biopsy were performed for staging procedures. Three-dimensional (3D) reconstruction and fusion of images were performed for better localization of lymph nodes (LNs). Detection of SLNs and the analysis of the radiotracer outflow was conducted with the use of single-photon emission-computed tomography/computed tomography (SPECT/CT) lymphangiography. Results: The mean age of the patients was 73.4 years; 7 (36%) were male. Pathological staging from the biopsy was T0—8 (42%), Ta—7 (36%), T1—4 (21%). SLNs were detected in two of 19 cases (10%). In one patient a single SLN (5.3%) was visualized, and in another case (5.3%), multiple (double) radioactive lymph nodes were visualized. In 17 out of the 19 (89.5%) cases, no lymphatic outflow was observed, and out of these five cases (26.3%) of gravitational leakage of injected radiotracer to the retroperitoneal space was noted. Conclusions: We demonstrated that detection of SLNs in the upper urinary tract is possible yet challenging. Radiotracer injection in the upper urinary tract during ureterorenoscopy is difficult to perform, and the expected result of injection is unsatisfactory. Lymphatic outflow from the tumor site to the first LNs in our studied group of patients is visible in 10.5% of cases. SPECT/CT lymphangiography in cases of UTUC may provide valuable information about a patient’s individual anatomy of the lymphatic system and the position of the first lymph nodes draining lymph with potential metastatic cells from the tumor.

Undifferentiated and dedifferentiated urological carcinomas: lessons learned from the recent developments

Loss of the morphological and immunophenotypic characteristics of a neoplasm is a well-known phenomenon in surgical pathology and occurs across different tumor types in almost all organs. This process may be either partial, characterized by transition from well differentiated to undifferentiated tumor component (=dedifferentiated carcinomas) or complete (=undifferentiated carcinomas). Diagnosis of undifferentiated carcinoma is significantly influenced by the extent of sampling. Although the concept of undifferentiated and dedifferentiated carcinoma has been well established for other organs (e.g. endometrium), it still has not been fully defined for urological carcinomas. Accordingly, undifferentiated/ dedifferentiated genitourinary carcinomas are typically lumped into the spectrum of poorly differentiated, sarcomatoid, or unclassified (NOS) carcinomas. In the kidney, dedifferentiation occurs across all subtypes of renal cell carcinoma (RCC), but certain genetically defined RCC types (SDH-, FH- and PBRM1- deficient RCC) seem to have inherent tendency to dedifferentiate. Histologically, the undifferentiated component displays variable combination of four patterns: spindle cells, pleomorphic giant cells, rhabdoid cells, and undifferentiated monomorphic cells with/without prominent osteoclastic giant cells. Any of these may occasionally be associated with heterologous mesenchymal component/s. Their immunophenotype is often simple with expression of vimentin and variably pankeratin or EMA. Precise subtyping of undifferentiated (urothelial versus RCC and the exact underlying RCC subtype) is best done by thorough sampling supplemented as necessary by immunohistochemistry (e.g. FH, SDHB, ALK) and/ or molecular studies. This review discusses the morphological and molecular genetic spectrum and the recent develoments on the topic of dedifferentiated and undifferentiated genitourinary carcinomas.

The Differential Diagnosis of Medullary-Based Renal Masses

CONTEXT.—

Renal malignancies can be divided into cortical- and medullary-based tumors, the latter of which classically infiltrate the renal parenchyma by extending between nonneoplastic structures. Although high-grade cortical tumors can rarely exhibit the same growth pattern, the infiltrative morphology should elicit a differential diagnosis to be considered in each case. However, these diagnoses can be challenging to distinguish, especially on small renal biopsy samples.

OBJECTIVE.—

To provide an overview of the clinical, gross, and microscopic findings; genetic and molecular alterations; and immunohistochemical evaluation of medullary-based renal tumors and other tumor types with overlapping morphologies and growth patterns.

DATA SOURCES.—

Literature review and personal observations were used to compile the information in this review.

CONCLUSIONS.—

Collecting duct carcinoma is a prototypical medullary-based tumor, and although diagnostic criteria exist, it remains a diagnosis of exclusion, especially with ancillary techniques aiding the recognition of established as well as more recently described neoplasms. Other medullary-based malignancies included in the differential diagnosis include renal medullary carcinoma/renal cell carcinoma unclassified with medullary phenotype, fumarate hydratase-deficient renal cell carcinoma, and upper tract urothelial carcinoma. Moreover, other rare entities should be excluded, including metastatic carcinoma, lymphoma, and melanoma. In addition to potential prognostic differences, accurate diagnoses can have important surgical and clinical management implications.

Unusual Faces of Bladder Cancer

Simple Summary

The spectrum of architectural and cytological findings in UC is wide, although transitional cell carcinoma, either papillary or flat, low- or high-grade, constitutes the majority of cases in routine practice. Some of these changes are just mere morphological variations, but others must be recognized since they have importance for the patient. The goal of this review is to compile this histological variability giving to the general pathologist a general idea of this morphological spectrum in a few pages. The review also updates the literature focusing specifically on the morphological and immunohistochemical clues useful for the diagnosis and some selected molecular studies with prognostic and/or diagnostic implications.

Abstract

The overwhelming majority of bladder cancers are transitional cell carcinomas. Albeit mostly monotonous, carcinomas in the bladder may occasionally display a broad spectrum of histological features that should be recognized by pathologists because some of them represent a diagnostic problem and/or lead prognostic implications. Sometimes these features are focal in the context of conventional transitional cell carcinomas, but some others are generalized across the tumor making its recognition a challenge. For practical purposes, the review distributes the morphologic spectrum of changes in architecture and cytology. Thus, nested and large nested, micropapillary, myxoid stroma, small tubules and adenoma nephrogenic-like, microcystic, verrucous, and diffuse lymphoepithelioma-like, on one hand, and plasmacytoid, signet ring, basaloid-squamous, yolk-sac, trophoblastic, rhabdoid, lipid/lipoblastic, giant, clear, eosinophilic (oncocytoid), and sarcomatoid, on the other, are revisited. Key histological and immunohistochemical features useful in the differential diagnosis are mentioned. In selected cases, molecular data associated with the diagnosis, prognosis, and/or treatment are also included.

Universal Mismatch Repair Protein Screening in Upper Tract Urothelial Carcinoma

OBJECTIVES

Universal screening of upper tract urothelial carcinoma (UTUC) for Lynch syndrome by mismatch repair (MMR) protein immunohistochemistry (IHC) has been recommended by some investigators. Herein, we assess this recommendation retrospectively by simulating its performance on a retrospective, unselected cohort of UTUCs, with comparison to the established setting of colorectal and endometrial adenocarcinoma.

METHODS

We assessed for complete loss of MMR protein (MLH1, MSH2, MSH6, and PMS2) IHC in 74 consecutive cases of UTUC and then tabulated clinical and pathologic factors. MMR findings from same-institution colorectal and endometrial adenocarcinomas were tabulated for comparison.

RESULTS

We observed loss of at least one MMR protein in 12% in our UTUC cohort (three MSH2/MSH6, three MSH6 only, one MLH1/PMS2, and two PMS2 only). Of these nine cases (seven males, two females, median age 67 years, five associated with colorectal adenocarcinoma), at least three (4% of the overall cohort) proved to be Lynch syndrome. Overall, MMR loss in UTUC was comparable to colorectal (11%; 50 of 471 cases) and endometrial (12%; 12 of 101 cases) adenocarcinomas.

CONCLUSIONS

The rate of MMR loss observed in UTUC was comparable to that in the established setting of colorectal and endometrial adenocarcinomas, supporting universal UTUC screening at our institution and others.

Clear cell variant, urothelial carcinoma of ureter: A rare entity

Clear cell variants of transitional cell carcinoma of upper urinary tract is extremely rare. Although clear cell of urinary bladder has been reported, its occurrence in the upper tract has not been reported readily in literature.

We present a case of 77 year old female who was suspected with TCC of the ureter, but was found to have clear cell variant on histology post radical nephroureterectomy.

This was the first such case in our institution.

Urothelial carcinoma: variant histology, molecular subtyping, and immunophenotyping significant for treatment outcomes

Although urothelial carcinoma (UC) has been recognised as a homogenous disease entity until recently, it exhibits widely diverse histological variants. Recent studies have revealed that some histological variants may serve as markers of very high risk for advanced cancers and poor prognoses. Certain histological variants can generate a pathological T stage, which may result in unnecessary surgery. Though platinum based chemotherapy is the standard treatment, the use of immune checkpoint inhibitors (ICIs) for UC treatment has become a major trend in oncology. UCs showing specific histological variants have responded exceptionally well to chemotherapy and ICIs. Currently, molecular studies base molecular classification on gene expression profile signatures in order to make diagnoses or predict responses to chemotherapies and ICIs. Notably, some histological variants correlate with specific molecular subtypes. The usefulness of immunophenotyping for classification purposes was recognised only recently. Immunophenotypes are classified into three categories according to lymphocyte distribution in or around the cancer cell nest: desert, excluded, and inflamed. This immunophenotyping has been increasingly shown to be of value in predicting the response to ICIs. This review describes the morphological characteristics of histological variants as well as the advantages and limitations in determining them, with particular reference to clinical benefits. Subsequently, we describe the concept of molecular classification and immunophenotypes, and their morphological features, which are easily interpreted and amenable to daily practice via hematoxylin and eosin staining. We also consider the clinical advantages, limitations, and issues encountered while using these in routine clinical practice.

[Lipid cell variant urothelial carcinoma of the renal pelvis. A case report and literature review]

There are many variants of urothelial carcinoma. One of the most infrequent is formed by cells with a lipid content and an adipose tissue appearance. Only 43 cases have been reported in the bladder, 2 in the renal pelvis and 1 case in the ureter. We present a third case in the renal pelvis; the patient is alive and free of disease 103 months post diagnosis.

A case report of primary upper urinary tract signet-ring cell carcinoma and literature review

Background

Upper tract urothelial carcinoma with pure non-urothelial histology is an exception but variants are present in ~ 25% of cases. Primary upper urinary tract signet -ring cell carcinoma is extremely rare.

Case presentation

We report the case of a 65-year-old male diagnosed primary upper urinary tract signet-ring cell carcinoma while underwent percutaneous nephrolithotomy. Radical nephroureterectomy and adjuvant chemotherapy were performed sequentially. The patient is now recovering well with a regular follow-up for more than 1 year.

Conclusions

The upper urinary tract malignancy often appears as a high grade, high stage tumor and has a uniformly poor prognosis, but a timely multimodal management can bring a good outcome.

European Association of Urology Guidelines on Upper Urinary Tract Urothelial Carcinoma: 2020 Update

CONTEXT

The European Association of Urology (EAU) Guidelines Panel on Upper Urinary Tract Urothelial Carcinoma (UTUC) has prepared updated guidelines to aid clinicians in the current evidence-based management of UTUC and to incorporate recommendations into clinical practice.

OBJECTIVE

To provide an overview of the EAU guidelines on UTUC as an aid to clinicians.

EVIDENCE ACQUISITION

The recommendations provided in the current guidelines are based on a thorough review of available UTUC guidelines and articles identified following a systematic search of Medline. Data on urothelial malignancies and UTUC were searched using the following keywords: urinary tract cancer, urothelial carcinomas, upper urinary tract carcinoma, renal pelvis, ureter, bladder cancer, chemotherapy, ureteroscopy, nephroureterectomy, neoplasm, adjuvant treatment, instillation, recurrence, risk factors, and survival. References were weighted by a panel of experts.

EVIDENCE SYNTHESIS

Owing to the rarity of UTUC, there are insufficient data to provide strong recommendations. The 2017 tumour, node, metastasis (TNM) classification is recommended. Recommendations are given for diagnosis and risk stratification as well as for radical and conservative treatment, and prognostic factors are discussed. A single postoperative dose of intravesical mitomycin after nephroureterectomy reduces the risk of bladder tumour recurrence. Kidney-sparing management should be offered as a primary treatment option to patients with low-risk tumour and two functional kidneys. After radical nephroureterectomy, cisplatin-based chemotherapy is indicated in locally advanced UTUC.

CONCLUSIONS

These guidelines contain information on the management of individual patients according to a current standardised approach. Urologists should take into account the specific clinical characteristics of each patient when determining the optimal treatment regimen, based on the proposed risk stratification of these tumours.

PATIENT SUMMARY

Urothelial carcinoma of the upper urinary tract is rare, but because 60% of these tumours are invasive at diagnosis, an appropriate diagnosis is most important. A number of known risk factors exist.

Rare primary lymphoepithelioma-like carcinoma of the renal pelvis

Lymphoepithelioma-like carcinoma (LELC) is a rare, malignant epithelial tumour which can arise within the upper urinary tract. This letter adds to a previous systematic review and cumulative analysis of 28 published upper urinary tract-LELC cases which provided insight into this disease; however, the current evidence does not provide clinicians with clear guidelines due to its rarity. Therefore, the aim was to report a new case of renal pelvis LELC presented in our hospital. In this instance, we were able to report treatment experience and long-term follow-up results. This patient presented with hypertension and haemturia which initiated further investigation. While ultrasound identified an hypechoic mass, no malignant cells were detected using cytological testing. Abdominal magnetic resonance imaging identified a slightly enhanced mass in the left renal pelvis with no evidence of lymph node metastasis. Ureteroscopic tumor biopsy suggested the existence of urothelial carcinoma, hence, laparoscopic radical left nephroureterectomy with bladder cuff excision was performed. Through patient-practitioner consultations, we decided to adopt a "watch and wait" approach after radical nephroureterectomy rather than administering chemotherapy. Although, we would encourage clinicians to record and publish cases to garner insight into this type of malignant disease.

Lymphoepithelioma-like carcinoma of the upper urinary tract: A systematic review of case reports

BACKGROUND

Lymphoepithelioma-like carcinomas (LELCs) are rare, malignant epithelial tumors, generally considered a subtype of squamous cell carcinoma. LELCs are undifferentiated and can occur in multiple tissues, although LELCs in the urinary tract are extremely rare. As such, evidence does not provide clinicians with guidelines for the best practices. Even though this is a rare disease, it is associated with high morbidity and mortality. Therefore, we must learn to differentiate LELC types and identify risk factors for early identification.

AIM

To develop an evidence base to guide clinicians treating primary LELCs of the upper urinary tract (UUT-LELC).

METHODS

We performed a systematic review of all reports on UUT-LELC from the first published case in 1998 until October 2019, according to the PRISMA. A database was then developed by extracting data from previously published reports in order to analyze interactions between clinical characteristics, pathological features, interventions and outcomes. Survival was analyzed using Kaplan–Meier estimates, which were compared using log rank tests.

RESULTS

A total of 28 previously published cases were identified for inclusion. The median age was 72 years with a male to female ratio of 4:3. Pure type LELCs were most common with 48.3% (n = 14), followed by 37.9% (n = 11) predominant LELCs and 3.4% (n = 1) focal LELCs. Epstein-Barr virus testing was negative in all cases. Fourteen patients received radical nephroureterectomy (RNU)-based intervention. Twenty-three patients survived with no evidence of further metastasis, although six died before the median 18 mo follow-up point. Survival analysis suggests pure histological subtypes, and patients who receive complete tumor resection have more favorable prognoses. As always in cancer care, early identification generally increases the probability of interventional success.

CONCLUSION

The most effective treatment for UUT-LELC is RNU-based therapy. Since cases are few in number, case reporting must be enhanced and publishing encouraged to both save and prolong lives.

Clinicopathologic analysis of upper urinary tract carcinoma with variant histology

We report on the clinicopathologic features of 115 cases of high-grade urothelial carcinoma of the upper urinary tract with variant histology present in 39 (34%). Variant histology was typically seen in high pathological stage (pT2-pT4) (82%, 32 cases) patients with lower survival rate (70%, 27 cases, median survival 31 months) and consisted in urothelial with one (23%), two (3%), and three or more variants (3%); 4% of cases presented with pure variant histology. Squamous divergent differentiation was the most common variant (7%) followed by sarcomatoid (6%) and glandular (4%), followed by 3% each of micropapillary, diffuse-plasmacytoid, inverted growth, clear cell glycogenic, or lipid-rich. The pseudo-angiosarcomatous variant is seen in 2%, and 1% each of nested, giant-cell, lymphoepithelioma-like, small-cell, trophoblastic, rhabdoid, microcystic, lymphoid-rich stroma, or myxoid stroma/chordoid completed the study series. Loss of mismatch repair protein expression was identified in one case of upper urinary tract carcinoma with inverted growth variant (3.6%). Variant histology was associated to pathological stage (p = 0.007) and survival status (p = 0.039). The univariate survival analysis identified variant histology as a feature of lower recurrence-free survival (p = 0.046). Our findings suggest that variant histology is a feature of aggressiveness in urothelial carcinoma of the upper urinary tract worth it to be reported.

Advancements in the clinical management of upper tract urothelial carcinoma

Introduction: Upper tract urothelial carcinoma (UTUC) remains a complex disease to manage given challenges in staging, surgical resection, use of perioperative therapy, and prevention of bladder recurrences. High-level evidence is limited to guide management; however, recent data have shifted treatment paradigms. We intend to review recent evidence on advancements in the clinical management for UTUC.Areas covered: This review summarizes advancements in pre-operative work-up, surgical technique, and the use of intravesical and systemic therapy in both the neoadjuvant and adjuvant settings. Special comment is made on progress in the genomics of UTUC and how that can inform clinical practice.Expert opinion: Advancements in the clinical management of UTUC are most prominently being made in the neoadjuvant chemotherapy setting. Although level I evidence is sparse, data from both single and multi-institutional retrospective studies strongly encourage the use of neoadjuvant chemotherapy especially in high-risk or advanced-stage patients.

Impact of squamous differentiation on intravesical recurrence and prognosis of patients with upper tract urothelial carcinoma

Background

The prognostic role of squamous differentiation in upper urinary tract urothelial carcinoma (UTUC) is still unclear. This article describes the impact of squamous differentiation on prognosis and intravesical recurrence of patients with primary UTUC treated with radical nephroureterectomy (RNU).

Methods

Totally, we retrieved (I) 669 histologically confirmed UTUC patients without histologic variants; (II) 101 UTUC patients with squamous differentiation in our institution, dating from April 2003 to April 2016. The clinical pathological characteristics and survival outcomes were compared between these two cohorts.

Results

In our study, 13% UTUC patients were detected with squamous differentiation. The mean age of all the patients examined was 66, of whom 70% were males. Squamous differentiation significantly associated with tumor stage, tumor grade and lymphovascular invasion. The Kaplan-Meier and Cox regression analyses showed that presence of squamous differentiation was correlated with shorter cancer specific survival of UTUC patients. The 5-year cancer specific survival rates were 47% for squamous differentiation-present patients and 63% for squamous differentiation-absent patients. UTUC patients with squamous differentiation showed a higher frequency of high-grade disease in advanced stage (pT2/pT3/pT4), while the discrepancy was not shown in early stage (pTa/pT1). Intravesical recurrence was observed in 27% patients. We found that intravesical recurrence had little impact on the cancer specific survival of squamous differentiation-present patients, yet it tended to decrease cancer specific survival among squamous differentiation-absent patients.

Conclusions

The presence of squamous differentiation in UTUC patients was a vital prognostic factor for cancer specific survival and correlated with intravesical recurrence after receiving RNU.

Primary renal pelvis and ureter squamous cell carcinoma (SCC): a rare case report and review of literature

Primary renal squamous cell carcinoma (SCC) is a very rare upper urinary tract neoplasm. Renal SCC has a poor prognosis because it usually presents in advanced stages. We report a 64-year-old woman with a right paravertebral mass; after right radical nephroureterectomy and salpingo-oophorectomy, pathologic examination revealed primary SCC.

[Comparative morphological characteristics and immunophenotype of urothelial carcinomas of the renal pelvis and bladder]

Urothelial carcinoma is one of the most frequently diagnosed malignant tumors of the bladder and upper urinary tract, which ranks seventh in the pattern of cancer. Urothelial carcinoma of the renal pelvis is less common; but has a more aggressive clinical course and a worse prognosis than that of the bladder. This is due to the clinical and morphological features of this form of cancer, which, unlike bladder cancer, have not been studied enough.

OBJECTIVE

To comparatively analyze the morphological and immunophenotypic parameters of urothelial carcinomas of the renal pelvis and bladder.

SUBJECT AND METHODS

Surgical specimens from 196 patients diagnosed with urothelial carcinoma of the renal pelvis and bladder were investigated. Paraffin sections were immunohistochemically examined using the standard protocol. Antibodies against CK5/6, CD138, CDX2 ('Dako'), CK7, CK14, CK20, CEA, CD10, CD117, EMA, E-Cadherin, HMWCK, p63, Uroplakin III, Vimentin ('Novocastra'), CD44, GATA-3, MUC1, MUC2, and MUC-5AC ('Cell Marque') were used.

RESULTS

Most tumors (n=147 (75%)) were invasive. Of them, 65 (33%) cases had a histological structure of conventional urothelial cancer; and 3 (1.5%) had paradoxical differentiation. Divergent tumor zones were verified in 66 (34%) neoplasms; 4 (2%) cases showed an inverted growth pattern. Pseudosarcomatous stroma reaction in the invasion zones was verified in 9 (5%) cases. The tumor stage corresponded to pT2-pT4 in 128 (65%) tumors.

CONCLUSION

Urothelial carcinomas of the renal pelvis and bladder show a broad spectrum of histological variants. The findings support that, unlike urothelial carcinomas of the bladder, the majority of primary urothelial carcinomas of the renal pelvis are high-grade and highly invasive.

Prognostic and therapeutic role of HER2 expression in micropapillary carcinoma of the bladder

Micropapillary carcinoma of the bladder (MPBC) is a variant type of infiltrating urothelial carcinoma, which portends a poor biological behavior in terms of disease stage at first diagnosis and clinical outcome; its peculiar morphology raises issues concerning the ability of tumor detection by imaging techniques and proper biopsy procedure, and the appropriate treatment for non-muscle infiltrating and muscle-infiltrating MPBC remains a matter of debate. On the basis of its established prognostic and therapeutic role in breast and gastro-esophageal cancer in the first instance, the human epidermal growth factor receptor-2 (HER2) has been investigated in selected case series of MPBC over the last 10 years. The aim of the present review was to summarize the existing evidence on HER2 status in MPBC, and to discuss its present and future utility in risk assessment and treatment choice of this uncommon, yet aggressive, disease.

Contemporary best practice in the management of urothelial carcinomas of the renal pelvis and ureter

Upper tract urothelial carcinoma (UTUC) accounts for 5% of urothelial carcinomas (UCs), the estimated annual incidence being 1-2 cases per 100,000 inhabitants. Similarly to bladder UC, divergent differentiations and histologic variants confer an adverse risk factor in comparison with pure UTUC. Molecular and genomic characterization studies on UTUC have shown changes occurring at differing frequencies from bladder cancer, with unique molecular and clinical subtypes, potentially with different responses to treatment. Systemic chemotherapy is the standard approach for patients with inoperable locally advanced or metastatic UCs. Although initial response rates are high, the median survival with combination chemotherapy is about 15 months. In first-line chemotherapy several cisplatin-based regimens have been proposed. For patients with advanced UC who progress to first-line treatment, the only product licensed in Europe is vinflunine, a third-generation, semisynthetic, vinca alkaloid. Better response rates (15-60%), with higher toxicity rates and no overall survival (OS) benefit, are generally achieved in multidrug combinations, which often include taxanes and gemcitabine. The US FDA has recently approved five agents targeting the programmed death-1 and programmed death ligand-1 pathway as a second-line therapy in patients with locally advanced or metastatic UC with disease progression during or following platinum-containing chemotherapy. Potential therapeutic targets are present in 69% of tumours analyzed. Specific molecular alterations include those involved in the RTK/Ras/PI(3)K, cell-cycle regulation and chromatin-remodeling pathways, many of them have either targeted therapies approved or under investigation. Angiogenic agents, anti-epidermal growth factor receptor therapy, phosphoinositide 3-kinase (PI3K) and mammalian target of rapamycin (mTOR) pathway inhibitors and immunotherapeutic drugs are being successfully investigated.

Upper urinary tract urothelial carcinoma and its variants: transition from morphology to personalized molecular characterization in diagnosis, prognosis, and therapy

INTRODUCTION

Upper tract urothelial carcinoma (UTUC) accounts for 5% of urothelial carcinomas (UCs), the estimated annual incidence being 1-2 cases per 100,000 inhabitants. The aim of this review was to summarize the main morphologic features of UTUC as well as the current status and future role of its molecular characterization in diagnosis, prognosis, and therapy. Areas covered: Several studies on the UTUCs have shown the diagnostic, prognostic, and therapeutic significance of standard pathological features, such as tumor stage, grade, and lymph node metastasis. Investigations have also identified novel factors, in particular, variant histologies, and molecular biomarkers. Based on these, predictive tools have been developed. Expert commentary: The morphology of the UTUC has been considered to be the same as that of Bladder Urothelial carcinoma (BUC). Molecular characterization studies, including genomics, have shown changes in UTUC occurring at differing frequencies in comparison with BUC, the former with unique molecular subtypes and different responses to treatment.

Reappraisal of HER2 status in the spectrum of advanced urothelial carcinoma: a need of guidelines for treatment eligibility

Although human epidermal growth factor receptor 2 (HER2) may represent a therapeutic target, its evaluation in urothelial carcinoma of the bladder does not rely on a standardized scoring system by immunohistochemistry or fluorescent in situ hybridization (FISH), as reflected by various methodology in the literature and clinical trials. Our aim was to improve and standardize HER2 amplification detection in bladder cancer. We assessed immunohistochemical criteria derived from 2013 American Society of Clinical Oncology (ASCO)/College of American Pathologists (CAPs) guidelines for breast cancer and investigated intratumoral heterogeneity in a retrospective multicentric cohort of 188 patients with locally advanced urothelial carcinoma of the bladder. Immunohistochemistry was performed on 178 primary tumors and 126 lymph node metastases, eligible cases (moderate/strong, complete/incomplete membrane staining) were assessed by FISH. HER2 overexpression was more frequent with 2013 ASCO/CAP than 2007 ASCO/CAP guidelines (p < 0.0001). The rate of positive HER2 FISH was similar between primary tumor and lymph node metastases (8%). Among positive FISH cases, 48% were associated with moderate/strong incomplete membrane staining that were not scored eligible for FISH by 2007 ASCO/CAP criteria. Among 3+ immunohistochemistry score cases, 67% were associated with HER2-positive FISH. Concordance between primary tumors and matched lymph node metastases was moderate for immunohistochemistry (κ = 0.54 (CI 95%, 0.41-0.67)) and FISH (κ = 0.50 (CI 95%, 0.20-0.79)). HER2-positive FISH was more frequent in micropapillary carcinomas (12%) and carcinoma with squamous differentiation (11%) than in pure conventional carcinoma (6%). Intratumoral heterogeneity for HER2 immunohistochemistry was observed in 7% primary tumor and 6% lymph node metastases; 24% positive HER2 FISH presented intratumoral heterogeneity. Our study suggests that HER2 evaluation should include an immunohistochemistry screening step with eligibility for FISH including incomplete/complete and moderate/strong membrane staining. Spatial or temporal intratumoral heterogeneity prompts to perform evaluation on both tumor and lymph node, and for each histological variant observed.

Sarcomatoid Variant of Urothelial Carcinoma of the Renal Pelvis with Inferior Vena Cava Tumour Thrombus: A Case Report and Literature Review

Sarcomatoid variant of urothelial carcinoma (SVUC) of the renal pelvis is a rare entity. To the best of our knowledge, around 25 cases of this neoplasm have been reported in the literature to date, most of which were of high stage. The inferior vena cava tumour thrombus, which is a hallmark of renal cell carcinoma (RCC), may rarely be found in urothelial carcinoma of renal pelvis. In this report, a case of SVUC associated with tumour extension to inferior vena cava is documented. This association has been encountered in only one previously reported case. The possibility of urothelial carcinoma of the renal pelvis should therefore be included in the differential diagnosis of tumour thrombus of the inferior vena cava.

Sarcomatoid Carcinoma of Renal Pelvis with Abundant Heterologous Osteosarcomatous Element: A Case Report

A 47-year-old male presented with haematuria and flank pain for two weeks. Ultrasonography and renal scan revealed a poorly functioning left kidney with multiple calculi. Simple nephrectomy was performed and the specimen revealed a mass in his renal pelvis which showed both carcinomatous and sarcomatous components on microscopy. The sarcomatous component consisted of diffuse pleomorphic osteoblasts with intervening lacy osteoid, giving an osteosarcoma-like appearance. These areas of tumour were strongly positive for vimentin and osteopontin. The carcinomatous component was transitional cell carcinoma. Patchy areas of squamous cell carcinoma which were positive for pancytokeratin on immunostaining were also seen. Few weeks later, the patient presented with metastatic lesions in the sacrum. After nephrectomy, the patient underwent palliative radiotherapy of the spine followed by sunitinib therapy. A month later, there was recurrence at the site of surgery. The patient succumbed to his illness within five months of diagnosis. This report describes an extremely rare case of carcinoma, renal pelvis with predominantly osteosarcomatous areas.

Caveolin-1 Expression in Upper Tract Urothelial Carcinoma

BACKGROUND

Improvement in postoperative risk stratification of upper tract urothelial carcinoma (UTUC) is required to better predict outcomes and counsel patients on adjuvant treatment.

OBJECTIVE

To validate the association between caveolin-1 and oncological outcomes in patients treated with radical nephroureterectomy (RNU) for UTUC.

DESIGN, SETTING, AND PARTICIPANTS

Caveolin-1 expression was evaluated via immunochemistry on a tissue microarray from 621 patients. Caveolin-1 was considered overexpressed when at least 50% of the tumor cells stained positive. The median follow-up in this retrospective study was 35 mo (interquartile range 16-65).

INTERVENTION

Radical nephroureterectomy.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Univariate and multivariable Cox proportional hazards regression models were used to assess the association between caveolin-1 expression and recurrence and cancer-specific mortality (CSM).

RESULTS AND LIMITATIONS

Caveolin-1 was overexpressed in 150 patients (24%). Overexpression was associated with higher pathological stage (p<0.001) and grade (p<0.001). In univariate analyses, overexpression of caveolin-1 was significantly associated with lower recurrence (hazard ratio [HR] 1.7, 95% confidence interval [CI] 1.2-2.6; p=0.004) and CSM (HR 1.8, 95% CI 1.2-2.7; p=0.005); however, multivariable analyses did not prove its independent association with outcomes. The study is limited by its retrospective nature.

CONCLUSIONS

Despite overexpression in a quarter of UTUC patients, caveolin-1 was not independently associated with oncological outcomes. Its use could be evaluated to improve clinical staging of biopsy specimens and to help in clinical decision-making regarding a kidney-sparing approach or neoadjuvant systemic treatment.

PATIENT SUMMARY

Development of a panel of prognostic and predictive markers is mandatory for patient consultations in the era of personalized medicine. We evaluated the role of caveolin-1 in a large series of patients treated with radical nephroureterectomy for upper tract urothelial carcinoma (UTUC) and found that it was not independently associated with oncological outcomes. Nevertheless, it was associated with adverse pathological features. Considering caveolin-1 in UTUC biopsy specimens could help in improving clinical staging and decision-making regarding a kidney-sparing approach or neoadjuvant systemic treatment.

Variant morphology in upper urinary tract urothelial carcinoma: a 14-year case series of biopsy and resection specimens

Upper urinary tract urothelial carcinoma exhibiting variant morphology, especially in higher-grade tumors, is a recognized phenomenon but has not been comparatively studied in biopsy versus resection material. We studied the morphologic patterns and clinicopathological features, and provide a comparison between biopsy and resection specimens. Consultation cases were evaluated separately to investigate for possible consultation bias. A total of 383 in-house cases from 352 patients including 314 resection specimens and 69 biopsies from 2001 to 2014 were reviewed from a single institution. Histologic type, tumor grade, invasion, pathologic stage, nodal status, metastasis, and the presence and type of variant morphology for each case were evaluated. Variant morphology was identified in 5 biopsy specimens (7.2%) and 42 resection specimens (13.4%). The most common variant morphologic pattern was squamous differentiation (16 cases, 4.5%) followed by an inverted growth pattern (8 cases, 2.2%). The presence of variant morphology in resection specimens had a significant association with higher tumor grade, higher pT stage, and nonpapillary configuration. Of 69 patients with biopsies, 31 had a subsequent resection. In comparison, 181 consultation cases from 168 patients showed variant morphology in 6 biopsies (7.1%) and 27 resections (28.1%). In conclusion, the frequency of recognizing variant morphology in biopsies is about one-half of that in resections. The inclusion of consultation cases can inflate the incidence of variant morphology. As a result, the frequency of variant morphology in our in-house cases is lower than the percentage reported in the literature, most likely secondary to a consultation bias.

Lymphoepithelioma-like carcinoma of the upper urinary tract

In this report, we summarized the clinicopathologic features of ten cases of lymphoepithelioma-like carcinoma (LELC) of the upper urinary tract (ureter n = 6; renal pelvis n = 4), a rare variant of urothelial cancer characterized by a malignant epithelial component densely infiltrated by lymphoid cells. The initial diagnosis was made on radical nephrectomy in five cases, nephroureterectomy in three cases, and ureterectomy in two others. Four patients had pathologic stage T1 (n = 2) or T2 (n = 2) tumors, and six patients had stage pT3 disease. Microscopically, all tumors contained pure (n = 3) or predominant (n = 7) LELC, which composed 60 to 80% of the entire tumor. Non-LELC tumor component was adenocarcinoma (n = 2), spindle cell carcinoma (n = 1), or high-grade conventional urothelial carcinoma (n = 4). The LELC component was characterized by indistinct cytoplasmic borders and a syncytial growth pattern. Immunohistochemical staining showed LELC to be positive for cytokeratin AE1/AE3, CK7, CK34ßE12 (rare cells), CK5/6 (rare cells), and CK20 (rare cells); rare cells were p40 positive. GATA 3 was positive in all cases in a variable proportion of cells (20-80%). Lymphoid markers showed a polyclonal proliferation of predominant T cells admixed with B cells. In situ hybridization for the HPV genome was negative in all ten cases. Survival analysis showed no differences between LELC and conventional upper urinary tract urothelial carcinoma, pT classification being the only significant prognostic parameter. Morphologic recognition and distinction from other (non-)neoplastic lesions with prominent lymphoid stroma are critical for its clinical management.

High Grade Mucinous Urothelial Carcinoma of the Renal Collecting System: A Case Report

High grade mucinous urothelial carcinoma is a rare pathological variant. There is still controversy as to its nomenclature and classification. We report the case of a 64 year old female with history of pelvic pain who was incidentally discovered to have a left upper pole renal mass. Left nephroureterectomy was performed and histopathological examination revealed high grade mucinous urothelial carcinoma. Accurate diagnosis of this distinct pathological entity will allow for better understanding of phenotypic behavior and inform best treatment strategies.

Photodynamic diagnosis in upper urinary tract urothelial carcinoma: A systematic review

Objective

To assess the diagnostic accuracy and safety of photodynamic diagnosis (PDD) in upper urinary tract urothelial carcinoma (UUTUC).

Materials and methods

A systematic literature search was conducted. Included studies were assessed for the risks of bias and quality using appropriate tools. Dedicated data extraction forms were used. Diagnostic accuracy in terms of sensitivity and specificity were quoted whenever provided by individual studies. A combined toxicity profile of 5-aminolevulinic acid (5ALA) was given after reviewing individual studies.

Results

In all, 17 studies were identified. After screening seven studies were included involving a total of 194 patients. None of the studies were randomised. All the available studies were of low-to-moderate quality. The largest available study, with 106 patients, reported a sensitivity of 95.8% and 53.5% for PDD and white-light (WL) ureterorenoscopy (URS) respectively, with a statistically significant difference. The specificity was 96.6% for PDD and 95.2% for WL-URS with no statistical significance. PDD showed better ability in detecting carcinoma in situ and dysplasia. One study compared PDD to computed tomography urogram (CTU) and found PDD to have better sensitivity and statistically significantly better specificity. 5ALA-associated toxicity was minor in nature and hypotension was the most common adverse event.

Conclusion

PDD in UUTUC appears to be more accurate than WL-URS and CTU, with no significant toxicity. Larger scale randomised trials are needed.