Endovascular management of a right external iliac artery–ureteral fistula after multimodal therapy for cervical cancer and prolonged metallic ureteral double-J stent

Abstract

We present a case of a 52-year-old woman with a ureteroarterial fistula. The patient had a history of radical hysterectomy, lymphadenectomy, chemotherapy, and radiotherapy for cervical cancer at age 44. Bilateral hydronephrosis was observed five years after surgery, and bilateral polyurethane double-J ureteral stents were inserted. In the sixth postoperative year, the stents were exchanged for metallic double-J stents. In the seventh year, the patient presented with gross hematuria. Contrast-enhanced CT suggested a fistulous connection between the right external iliac artery and the ureter. Placement of an endovascular stent graft resulted in resolution of hematuria.

Highlights

• •Ureteroarterial fistula (UAF) may cause fatal hematuria if diagnosed late.
• •This case links UAF to long-term metallic stents after cervical cancer treatment.
• •Endovascular stent grafting can treat right external iliac artery–ureter fistula.
• •Fever resolved after metallic stent was replaced, suggesting a risk of infection.
• •One year post-discharge, patient remains symptom-free with regular follow-up.

1. Introduction

Ureteroarterial fistula (UAF) is a rare but potentially fatal condition involving abnormal communication between a ureter and an adjacent artery, which can result in life-threatening gross hematuria if diagnosis or treatment is delayed. Known risk factors include prior pelvic surgery, radiation therapy for malignancy, and long-term ureteral stenting.¹ Recent reports have addressed associations between UAF development and the type or duration of ureteral stent placement; however, limited data are available on the role of metallic ureteral stents in UAF pathogenesis.

This report presents a case of a right external iliac artery–ureteral fistula that developed following multimodal therapy for cervical cancer, including prolonged placement of metallic ureteral stents, and was successfully managed with endovascular treatment.

2. Case presentation

A 52-year-old woman presented to the emergency department with gross hematuria. Her medical history included multimodal treatment for cervical cancer and bilateral ureteral stenting for bilateral hydronephrosis as a late complication. At 44 years of age, she was diagnosed with stage IIIC2 cervical squamous cell carcinoma according to the FIGO classification. She underwent radical hysterectomy with pelvic and para-aortic lymphadenectomy, followed by postoperative radiotherapy targeting the whole pelvis and para-aortic lymph nodes (total dose 50.4 Gy) in combination with concurrent chemotherapy consisting of cisplatin and paclitaxel. No evidence of disease recurrence was observed during follow-up. At five years postoperatively, renal dysfunction was identified during a routine health examination. Computed tomography (CT) revealed bilateral hydronephrosis, and bilateral polyurethane double-J ureteral stents (hereafter referred to as common DJs) (InLay Optima® ureteral stents) were inserted. In the sixth postoperative year, the polyurethane stents were exchanged for metallic double-J stents (hereafter referred to as metal DJs) (RUSCH Tumor stents®).

Upon presentation to the emergency department, laboratory analysis showed hemoglobin of 11.2 g/dL and serum creatinine of 4.40 mg/dL. Non-contrast CT demonstrated high-density areas in the right renal pelvis and upper ureter consistent with bleeding, as well as similar findings in the bladder indicative of hematoma (Fig. 1). Bleeding secondary to irritation from the metal DJ was suspected. A 22Fr 3-way urethral catheter was placed, continuous bladder irrigation was initiated, and the patient was admitted for further management.

Fig. 1.

Non-contrast CT showing high-attenuation areas extending from the right renal pelvis to the upper ureter (arrows), suggestive of hemorrhage. Similar high-attenuation areas, consistent with hematoma, are noted in the bladder (arrowheads).

On hospital day 6, hemoglobin decreased to 6.5 g/dL, prompting transfusion of 4 units of red blood cells. Cystoscopy revealed a large bladder hematoma without active bleeding. Transurethral evacuation of the hematoma was performed on hospital day 10. No bleeding was observed from the bladder wall or ureteral orifices.

On day 11, gross hematuria (grade 3) recurred. Contrast-enhanced CT was performed following preparation for emergency dialysis. A bulging lesion was identified at the crossing of the ureter and right external iliac artery, raising suspicion of a ureteroarterial fistula (Fig. 2).

Fig. 2.

Contrast-enhanced CT demonstrating a focal protrusion at the crossing point between the right external iliac artery and the ureter (an arrow).

On day 12, an endovascular stent graft (GORE EXCLUDER®) was deployed in the right external iliac artery, and coil embolization of the right internal iliac artery was performed to prevent rebleeding from potential endoleak into the fistula (Fig. 3). Coil embolization was necessary as retrograde perfusion through collateral branches of the internal iliac artery could maintain blood flow into the fistula even after stent graft placement in the external iliac artery, potentially leading to persistent or recurrent bleeding. Hematuria resolved after the procedure; however, fever and elevated CRP levels persisted. Blood cultures were negative, but Enterococcus faecium was isolated from urine collected during the stent graft procedure. Considering possible vascular graft infection associated with the metal DJ, vancomycin therapy was initiated on day 18.

Fig. 3.

Coil embolization of the right internal iliac artery (arrows) and stent graft placement in the right external iliac artery (arrowheads) were performed.

Fever persisted, and on day 32, the metallic ureteral stent was exchanged for a single-J stent (SJ, BIOSIS mono-J stent®), resulting in defervescence.

On day 42, the SJ was replaced with a conventional DJ stent, and the patient was discharged on day 50.

At present, one year after discharge, the patient remains free of hematuria and infection recurrence and continues regular follow-up visits for periodic ureteral stent exchange.

3. Discussion

UAF was first described by Moschcowitz in 1908.² It represents a potentially life-threatening condition due to the risk of massive hemorrhage. Although historically considered rare, the incidence of UAF appears to be increasing with the advancement of cancer therapies and prolonged patient survival.³

UAFs are classified as primary (15 %) or secondary (85 %). Primary UAFs are associated with arterial aneurysms, vascular malformations, or direct invasion of abnormal vessels into the ureter.¹ Secondary UAFs are most commonly related to long-term ureteral stenting (80 %), prior pelvic surgery (65 %), and pelvic radiotherapy (53 %; average dose, 52 Gy).³

The precise pathophysiology of UAF remains unclear. However, it is postulated that pelvic surgery and radiation therapy result in fibrosis and ischemic damage to the arterial wall, leading to adherence of the ureter to adjacent arteries. Chronic mechanical friction from arterial pulsation may subsequently create a fistulous connection between the artery and the ureter.⁴

In the present case, the patient had received multimodal treatment for cervical cancer and had long-term bilateral ureteral stents in place, encompassing all major risk factors for UAF. In addition, the prior pelvic and para-aortic lymphadenectomy likely induced fibrosis of the right external iliac artery wall, further contributing to UAF development.

Metallic ureteral stents provide advantages over polyurethane stents, including prolonged patency and reduced need for frequent exchange. However, increased rigidity and greater mechanical pressure on adjacent vessels may elevate the risk of fistula formation.⁵ In this case, placement of a metallic ureteral stent in a patient with multiple predisposing factors may have contributed to UAF onset.

Reported sensitivities for UAF detection are 48 % for contrast-enhanced CT, 51 % for retrograde ureterography, and 62 % for angiography, with angiography considered the most reliable tool.³ In this case, contrast-enhanced CT could not be performed initially due to significant renal dysfunction, delaying diagnosis. Subsequent imaging revealed a protrusion of the right external iliac artery at the ureteral crossing, confirming the diagnosis of UAF.

Historically, open surgical approaches such as vascular bypass or grafting were standard treatment options. However, recent advances in endovascular techniques have established stent graft placement as the preferred first-line treatment due to its minimally invasive nature.³ Given the anticipated severe pelvic adhesions resulting from prior surgery and radiotherapy, endovascular treatment was considered appropriate in this case. The fistula was successfully closed using a GORE EXCLUDER® stent graft placed from the right common to external iliac artery, along with coil embolization of the right internal iliac artery to prevent endoleak.

Potential complications of endovascular repair include thromboembolism, lower limb or visceral ischemia, skin ulceration, and, most critically, graft infection, which carries a reported mortality rate of 33 %–58 %.⁶ This patient had asymptomatic bacteriuria due to long-term ureteral stenting, raising the risk of graft infection through the fistulous tract. Postoperatively, E. faecium was isolated from urine, and persistent fever with elevated CRP was observed. However, with prolonged vancomycin administration and replacement of the ureteral stent, the infection was successfully controlled without graft-related complications.

4. Conclusion

Placement of metallic ureteral stents after multimodal therapy for malignancy may contribute to UAF development. Endovascular intervention remains the first-line therapeutic option; however, vigilant postoperative monitoring is essential to identify potential graft infection.

CRediT authorship contribution statement

Gensuke Okazaki: Writing – original draft, Data curation, Conceptualization. Tomoki Okada: Supervision. Yosuke Tsukii: Supervision. Yusuke Noda: Supervision. Yuya Ohta: Supervision. Satoshi Kurokawa: Writing – review & editing, Supervision, Project administration. Takahiro Yasui: Supervision.

Consent

Informed consent for publication was provided by the patient.

Funding

This research did not receive any specific grants from funding agencies in the public, commercial, or not-for-profit sectors.

Declaration of competing interest

The authors declare no conflicts of interest.

Glossary:

DJ

double-J ureteral stent

SJ

single-J ureteral stent

UAF

ureteroarterial fistula