CT Urography Findings of Upper Urinary Tract Carcinoma and Its Mimickers: A Pictorial Review

Pilot study: Urine cell-free DNA with low-pass whole genome sequencing can detect and molecularly type upper tract urothelial carcinomas

OBJECTIVES

Upper tract urothelial carcinoma (UTUC) is an aggressive disease that is challenging to biopsy and diagnose, frequently yielding nondiagnostic cytology and tissue specimens. Therefore, UTUC is often late stage when diagnosed, with poor outcomes. Cell-free tumor DNA (cfDNA) may improve UTUC early diagnosis and assessments of heterogeneity, treatment response, and recurrence but has not been studied in the urine from patients with UTUC. This study aimed to detect recurrent, diagnostic UTUC cytogenetic abnormalities by low-pass whole genome sequencing (LPWGS) and to compare urine-derived and plasma cfDNA against abnormalities identified in patient tumor tissue.

METHODS

Cell-free tumor DNA extracted from voided urine and plasma before nephroureterectomy in 4 patients with UTUC was compared with genomic DNA from formalin-fixed, paraffin-embedded tumor tissue after LPWGS.

RESULTS

Abnormal autosomal genomic regions were highest in tissue (n = 11,843), intermediate in urine (n = 5,072) and lowest in plasma (n = 763), with a high concordance of flagged regions identified in tissue and urine (r = 0.88). Pairwise analysis of whole chromosome gains/losses and subchromosomal alterations between tissue and urine showed nearly identical patterns in all 4 patients (r = 0.88-0.99) in contrast to plasma (r < 0.25). Abnormal genomic regions identified by LPWGS showed a high degree of overlap (100% for tumor tissue, 94% for urine cfDNA) with cBioPortal UTUC-associated genes.

CONCLUSIONS

We demonstrated the superiority of urine vs plasma cfDNA when LPWGS was used to identify UTUC-associated gene abnormalities. Voided urine cfDNA molecular signatures are highly concordant with matched tumor tissue on chromosomal and subchromosomal levels, emphasizing its feasibility as a noninvasive biomarker for UTUC detection and surveillance.

Urologic Imaging of Collecting System and Ureters: Cancers and Mimics

Urothelial carcinoma can arise from any portion of the urothelial lining extending from the kidneys to the urethra, with morphologic subtypes including papillary, polypoid, infiltrative, and ulcerative growth patterns. Imaging plays a crucial role in detecting upper and lower urinary tract tumors and in differentiating them from other benign mimics. Computed tomographic urography (CTU) is the imaging modality of choice for the diagnosis of urothelial carcinoma as well as for noninvasive surveillance following treatment. CTU allows evaluation of recurrent primary tumor while evaluating for metastatic disease in a single study.

Imaging review of spontaneous renal hemorrhage

Spontaneous renal hemorrhage (SRH) is a diagnostic challenge and a significant cause of morbidity, and sometimes mortality. Early identification is essential to institute lifesaving and reno-protective interventions. In this review, we classify spontaneous renal hemorrhage by location, presentation and etiology. We also discuss the diagnostic approach to renal hemorrhage and optimum imaging modalities to arrive at the diagnosis. Finally, we review strategies to avoid missing a diagnosis of SRH and discuss the pitfalls of imaging in the presence of renal hemorrhage.

Radiotherapy induced ureteric stenosis in locally advanced cervical cancer: A review of current evidence

BACKGROUND

Concurrent chemo-radiation followed by high dose rate brachytherapy is the standard of care for locally advanced cervical cancer. The proximity of the ureters to the tumor volume risks ureteric stenosis. Here we outline the current understanding of radiotherapy induced ureteric stenosis in patients treated for cervical cancer, focusing on the incidence, risk factors, clinical consequences, and management.

METHODS

Searches on EMBASE, PubMed, Science Direct, and Google Scholar were performed for publications reporting on radiotherapy, cervix cancer and ureteric stenosis. Multi and single center, prospective/retrospective, cohort, and cross-sectional studies were included.

RESULTS

This narrative review identified key issues relevant to radiation induced ureteric stenosis in cervical cancer in the literature. Thirteen studies were evaluated, identifying crude and actuarial rates of ureteric stenosis of 0.3-13.5% and 1.5-4.4% (at 5 years) respectively. The risk of ureteric stenosis is highest in the first 5 years after radiotherapy but continues to occur at a rate of 0.15% per year. Risk factors including advanced FIGO stage, tumor size >5 cm and baseline hydronephrosis increase the incidence of ureteric stenosis. EQD2 doses of ≥ 77Gy were significantly associated with ≥grade 3 ureteric morbidity. The majority of patients were managed with nephrostomy +/- ureteric stent insertion, with some requiring ureteral reimplantation, urinary diversion or nephrectomy.

CONCLUSIONS

This review has identified multiple considerations, highlighting the need to identify patients highest at risk of ureteric stenosis. There is also a need to recognize ureters as organs at risk, record dose exposure, and apply dose constraints, all of which set the landscape for allowing dose optimization.

Metastatic upper tract urothelial carcinoma with nest-like features presenting as malignant pleural effusion

Metastatic urothelial carcinoma is a rare cause of pleural effusions. We report a case of urothelial carcinoma of the upper urinary tract in an oldest-old male patient, a smoker, with situs inversus totalis, that presented uniquely with malignant pleural effusion at presentation without evidence of a primary tumor on imaging. Cytological smears of the massive left pleural effusion revealed epithelioid neoplastic cells arranged in short cords, small-to-large clusters, and raspberry-like morules, mimicking mesothelioma; cell block preparations highlighted the presence of tubules and nest-like structures. The tumor cells showed a high nuclear-to-cytoplasmic ratio, nuclear grooves, and mitotic figures. Cytomorphologic features coupled with the immunophenotype of neoplastic cells (p63, GATA3, and uroplakin II positive) allowed the diagnosis of metastatic urothelial carcinoma and a possible nested subtype. These findings were supported by a total body computed tomography (CT) showing no evidence of a mass in the bladder or elsewhere in the urinary tract but a concentric parietal thickening of the proximal left ureter, suggesting malignancy. To our knowledge, a malignant effusion as a primary manifestation of urothelial carcinoma with nest-like features originating in the upper urinary tract has never been described previously. Our case focuses on the value of cell block in the working-up of neoplastic effusions by revealing the architectural pattern of an uncommon malignancy and the correlation between cytopathology and imaging gross findings to reach an accurate diagnosis.

The Utility of Intraluminal Therapies in Upper Tract Urothelial Carcinoma: A Narrative Review

Nephron sparing surgery (NSS) is considered for selected cases of upper tract urothelial carcinoma (UTUC) as it maintains renal function and avoids morbidity associated with radical nephroureterectomy (RNU). The appropriate selection of patients suitable for NSS without compromising oncological outcomes can sometimes be difficult, given the limitations of diagnostic modalities. Recurrence rates for UTUC can be as high as 36 to 54% after NSS. Intraluminal adjuvant therapy can be attempted following NSS to reduce recurrence, but delivery to the upper tract is more challenging than into the bladder. Bacillus Calmette-Guerin (BCG) and chemotherapy such as Mitomycin (MMC) have been administered via nephrostomy or ureteric catheter, which requires invasive/repeated instrumentation of the upper urinary tract. Drug delivery by reflux from bladder instillation along indwelling stents has also been tried but can potentially be unreliable. Recently, a gel formulation of mitomycin has been developed for the controlled exposure of the upper urinary tract to treatment over a number of hours. Drug-eluting stents to deliver chemotherapy to the upper urinary tract have been developed but have not yet entered clinical practice. Endoluminal phototherapy utilising an intravenous photosensitising agent is another novel approach that has recently been described. Intraluminal therapies may be beneficial in decreasing recurrence rates in UTUC, but currently have some limitations in their usage.

Atypical presentations of UTUC: a case report of three patients

Background

Upper tract urothelial carcinoma (UTUC) is a rare clinical condition primarily characterized by symptoms such as gross or microscopic hematuria, flank pain, and renal colic. Although computed tomography urography (CTU) is currently the most accurate imaging modality for diagnosis, atypical presentations and physical examination findings can sometimes obscure lesions, posing diagnostic challenges.

Case presentation

In this report, three patients exhibited atypical symptoms, sharing a common complaint of flank pain. Notably, the first patient, who had recently undergone laparoscopic right duplex nephrectomy, presented with microscopic hematuria, whereas the other two did not show any gross or microscopic hematuria. Computed tomography urography revealed hydronephrosis and infection without significant renal pelvic space-occupying lesions, with persistently elevated white blood cell (WBC) counts, but no fever. These atypical clinical presentations confounded clinicians, delaying the diagnosis of upper tract urothelial carcinoma until postoperative pathological examination for the first two patients and resulting in advanced-stage diagnosis for the third patient. Postoperative pathology confirmed high-grade invasive upper tract urothelial carcinoma in all three patients.

Conclusion

Upper tract urothelial carcinoma can manifest atypically without hematuria and may be challenging to visualize on computed tomography urography, potentially leading to misdiagnosis. Therefore, clinicians should maintain a high level of suspicion for malignant tumors when patients exhibit hydronephrosis, infection on imaging, and persistently elevated white blood cell counts without fever, even in the absence of typical signs of upper urothelial carcinoma on computed tomography urography.

Cornerstones of CT urography: a shared document by the Italian board of urogenital radiology

CT urography is a single term used to refer to different scanning protocols that can be applied for a number of clinical indications. If, on the one hand, this highlights the role of the radiologist in deciding the most suitable technique to perform according to the patient's needs, on the other hand, a certain confusion may arise due to the different technical and clinical variables that have to be taken into account. This has been well demonstrated by a previous work based on an online questionnaire administered to a population of Italian radiologists that brought out similarities as well as differences across the national country. Defining precise guidelines for each clinical scenario, although desirable, is a difficult task to accomplish, if not even unfeasible. According to the prementioned survey, five relevant topics concerning CT urography have been identified: definition and clinical indications, opacification of the excretory system, techniques, post-processing reconstructions, and radiation dose and utility of dual-energy CT. The aim of this work is to deepen and share knowledge about these main points in order to assist the radiology in the daily practice. Moreover, a synopsis of recommendations agreed by the Italian board of genitourinary imaging is provided.

Renal papillary hypertrophy, a rare mimicker of upper tract urothelial carcinoma: A case report

Renal papillary hypertrophy is a rare variation that mimics upper tract urothelial carcinoma. This is the ninth case in literature. It causes hematuria and pain, or it could be asymptomatic. It is important to distinguish this variation from malignant masses since misdiagnosis leads to unnecessary radical surgery. Flexible ureteroscopy helps distinguish malignant from benign masses, particularly in cases where there is not a consensus on the exact pathology of the mass. We present a 46-year-old female who came with hematuria and was planned to undergo radical nephroureterectomy under the impression of renal cell carcinoma based on imaging studies. After flexible ureteroscopy, renal papillary hypertrophy was confirmed and radical nephroureterectomy was prevented.