Ureteral pseudodiverticula: frequent association with uroepithelial malignancy

What a difference a delay makes! CT urogram: a pictorial essay

PURPOSE

The aim of this pictorial essay is to demonstrate several cases where the diagnosis would have been difficult or impossible without the excretory phase image of CT urography.

METHODS

A brief discussion of CT urography technique and dose reduction is followed by several cases illustrating the utility of CT urography.

RESULTS

CT urography has become the primary imaging modality for evaluation of hematuria, as well as in the staging and surveillance of urinary tract malignancies. CT urography includes a non-contrast phase and contrast-enhanced nephrographic and excretory (delayed) phases. While the three phases add to the diagnostic ability of CT urography, it also adds potential patient radiation dose. Several techniques including automatic exposure control, iterative reconstruction algorithms, higher noise tolerance, and split-bolus have been successfully used to mitigate dose. The excretory phase is timed such that the excreted contrast opacifies the urinary collecting system and allows for greater detection of filling defects or other abnormalities. Sixteen cases illustrating the utility of excretory phase imaging are reviewed.

CONCLUSIONS

Excretory phase imaging of CT urography can be an essential tool for detecting and appropriately characterizing urinary tract malignancies, renal papillary and medullary abnormalities, CT radiolucent stones, congenital abnormalities, certain chronic inflammatory conditions, and perinephric collections.

Bilateral Pyelonephritis in a Cat with Multiple Urinary Malformations Including Ureteral Pseudodiverticulosis

Ureteral pseudodiverticulosis is an unusual acquired abnormality in humans and dogs. This report describes the first feline case of ureteral pseudodiverticulosis, associated with right retrocaval ureter and malposition of the uretero-vesical junctions, in the context of pyelonephritis. The coexistence of pseudodiverticulosis with other urinary abnormalities suggested that this lesion should be considered in other patients with urinary pathology.

Ureteral pseudodiverticulosis and urothelial cell carcinoma: rethinking the association

PURPOSE

To compare frequency of new and recurrent urothelial cell carcinoma (UCC) among patients with and without pseudodiverticulosis on imaging.

METHODS

This retrospective case-control study compared all 113 sequential patients with ureteral pseudodiverticulosis on radiographic urography between 1/1/2002 and 12/31/2012. Six patients were lost to follow-up. 107 patients without pseudodiverticulosis were matched by imaging modality, clinical indication, and tumor grade. Known UCC and primary outcome of new or recurrent UCC were determined through pathology on cystoscopy or clinical follow-up.

RESULTS

Nearly half of patients with pseudodiverticulosis had known UCC at the time of imaging (49/107, 46%). Mean cystoscopy follow-up was 7.0 and 4.6 years for pseudodiverticulosis cases with and without known UCC, respectively, and 7.5 and 7.3 years for controls, respectively. Mean clinic follow-up was 7.5 and 6.0 years for pseudodiverticulosis cases with and without known UCC, respectively, and 6.4 and 7.6 years for controls, respectively. Among patients with known UCC at the time of imaging, similar rates of recurrent UCC were demonstrated on follow-up among patients with pseudodiverticulosis (6/49, 12%) and without (7/49, 14%). Among patients with no known history of UCC at the time of imaging, no patients with pseudodiverticulosis developed UCC on follow-up and 5% (3/58) of patients without pseudodiverticulosis developed UCC.

CONCLUSION

Although half of patients with ureteral pseudodiverticulosis have a known diagnosis of UCC, the presence of pseudodiverticulosis did not signify an increased likelihood of developing new or recurrent UCC over the follow-up period.

Ureteral pseudodiverticulosis accompanied by urothelial carcinoma diagnosed by CT urography: a case report and review of the literature

Ureteral pseudodiverticulosis is a relatively rare condition and has been diagnosed by retrograde urography and excretory urography. Ureteral pseudodiverticulosis is also suspected to be a potential risk factor for the development of urothelial carcinoma. We report the case of a male in his 70 s who was suspected to have right ureteral pseudodiverticulosis accompanied by multifocal urothelial carcinoma based on CT urography findings. After surgery, the pathological findings confirmed the presence of ureteral pseudodiverticulosis and multifocal urothelial carcinoma in his right ureter and bladder. To the best our knowledge, this is the first reported case of ureteral pseudodiverticulosis with concurrent urothelial carcinoma detected by CT urography. Since CT urography has replaced excretory urography as the first-line imaging test for investigating patients with high risk for upper tract urothelial carcinoma, it is important to recognize the characteristic findings of ureteral pseudodiverticulosis on CT urography.

A novel case presenting with an unusual ureteral diverticular lesion similar to adenomyomatous hyperplasia of the gallbladder

We present the first case of an unusual ureteral diverticular lesion demonstrating similarities to adenomyomatous hyperplasia of the gallbladder. A 68-year-old asymptomatic Japanese man with high prostate-specific antigen levels was clinically evaluated. Left hydronephrosis and benign prostatic hyperplasia were detected. A bilateral retrograde pyelogram revealed that the upper and middle portions of the left ureter exhibited an irregular narrow lumen and some pooling of contrast material, which was compatible with ureteral pseudodiverticulosis. Although no malignant cells were seen on cytology, computed tomography detected a fusiform shaped lesion with a circumferential thick wall including multiple diverticulae. Left nephroureterectomy was performed because malignancy could not be ruled out. Pathology demonstrated that the ureteral lesion showed a localized thick wall consisting of multilocules and/or multicysts and a hyperplastic muscularis propria. The cysts were mostly seen in the muscularis propria or a deeper site. The inner layers of the cysts were lined with normal urothelium, and some cysts opened onto the mucosal surface, indicating that they were derived from invaginated mucosal epithelium. We believe that this lesion may be a novel form of diverticular disorder demonstrating similarities to adenomyomatous hyperplasia of the gallbladder.

Ureteral pseudodiverticulosis: a unique case diagnosed by multidetector computed tomography

Presented is a case of ureteral pseudodiverticulosis diagnosed by multidetector computed tomography (CT). Axial and coronal reformatted CT images revealed multiple small (2-4 mm) outpouchings of both ureters, characteristic of ureteral pseudodiverticulosis. The unenhanced CT also revealed a 6-mm stone at the left ureterovesical junction and a high attenuation lesion at the right ureterovesical junction suspect for an associated uroepithelial neoplasm.

Correlation Between Filling Defect Patterns on Urography and Pathologic Staging of Ureteral Transitional Cell Carcinomas

Although a filling defect within the ureter is the most common finding with ureteral transitional cell carcinomas (TCCs), little is known about the correlation between filling defect patterns and pathologic findings. This study was conducted to address this. Between January 1995 and January 2003, 126 pathologically confirmed TCCs of the ureter were included in our study. We classified urographic filling defects into four patterns: ovoid, polypoid, infiltrating, and plaque-like. The correlation between different filling defect patterns and pathologic findings was assessed using Pearson's Chi-squared and logistic regression methods. There were 28 (22%) ovoid filling defects, 42 (33%) polypoid filling defects, 37 (29%) infiltrating filling defects, and 19 (15%) plaque-like filling defects. Infiltrating and plaque-like filling defects were significantly associated with more advanced disease compared to ovoid and polypoid filling defects (odds ratio, 6.75; 95% confidence interval, 3.04-14.98; p < 0.0001). Our results suggest that filling defect presentations may signify different invasive behavior among TCCs. The distribution of ovoid, polypoid, infiltrating, and plaque-like filling defect patterns is significantly different between superficial and advanced ureteral TCCs. We suggest that classifying the filling defect patterns of ureteral TCCs may provide important preoperative information for planning treatment and predicting outcome.

Ureteral diverticula in two dogs

We describe ureteral diverticula in two dogs and briefly review the related literature. The diagnosis of this condition is radiographic and based on the excretory urographic observation of multiple ureteral outpouchings. Pathologically, ureteral transitional cell hyperplasia and mucinous metaplasia result in submucosal proliferation of the urothelium and the formation of crypts and small cysts. Ureteral diverticulosis in humans is associated with an increased risk of urothelial malignancies, such as transitional cell carcinoma of the urinary bladder. Clinically, both dogs were older, small breed neutered females. Both had a history of chronic urinary obstruction. One dog died during surgery to remove an adrenal mass, and the other was euthanized at the owner's request because of an inoperable bladder neoplasm. Histopathologic diagnosis of ureteral lesions confirmed the radiographic diagnosis of ureteral diverticula in both dogs.