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Fatal Recurrent Ureteroarterial Fistulas after Exenteration for Cervical Cancer
Gynecologic Oncology 82, 192–196 (2001) doi:10.1006/gyno.2001.6231, available online at http://www.idealibrary.com on
CASE REPORT Fatal Recurrent Ureteroarterial Fistulas after Exenteration for Cervical Cancer S. E. DePasquale, M.D.,* ,1 I. Mylonas,* ,† and S. S. Falkenberry, M.D.* *Brown University School of Medicine and Affiliations Program in Woman’s Oncology, Woman and Infants Hospital, Providence, Rhode Island 02905-2499; and †Medical Faculty, University of Rostock, 18055 Rostock, Germany Received December 27, 2000; published online May 31, 2001
CASE REPORT
Background. Ureteroarterial fistula (UAF) is a rare occurrence. It can be difficult to diagnose with a high mortality. We report a case of a recurrent UAF. Case. A 38-year-old women diagnosed with cervical cancer had undergone pelvic exenteration for severe radiation-induced necrosis with a vesicovaginal and rectovaginal fistula after primary radiation therapy. Hemorrhage into the urinary tract necessitated surgical intervention and vascular repair with a femoral–femoral bypass. Although these measures were effective, the patient died 6 months later following an acute hemorrhage into her conduit. Arteriogram revealed a second UAF. Conclusion. When urinary tract bleeding occurs in patients previously diagnosed with a gynecologic malignancy and treated with radiation therapy and extensive surgery with urinary diversion, UAF should be considered in the differential diagnoses. © 2001 Academic Press
A 38-year-old woman was initially evaluated by the Gynecological Oncology Service and found to have a FIGO stage IIIb squamous cell carcinoma of the cervix with left hydronephrosis in November 1995. A CT scan was significant for a large left adnexal mass, an enlarged uterus, and left hydronephrosis and hydroureter. She underwent examination under anesthesia and was diagnosed with a stage IIIb squamous carcinoma of the cervix. A left percutaneous nephrostomy tube was placed after cystoscopic retrograde ureteral stent placement was unsuccessful due to extrinsic tumor compression. That same month she underwent pretreatment staging, with an exploratory laparotomy revealing negative paraaortic lymph nodes and left salpingo-oophorectomy with positive findings of squamous cell carcinoma on the left oviduct. She then received 4500 cGy radiation therapy to the pelvis using a four-field technique and 2440 cGy to point A with two Fletcher implants. The parametrial tissue received a 720-cGy boost using a AP/PA technique. She also received six weekly cycles of cisplatin chemotherapy (40 mg/m 2) as a radiosensitizer. Ten months later, large rectovaginal and vesicovaginal fistulas were diagnosed. Clinical and radiographic evaluation revealed extensive tissue necrosis and radiation fibrosis with no evidence of recurrent disease. After failure of conservative measures including bowel rest with hyperalimentation, a total pelvic exenteration with formation of a continent ileal– colonic conduit was performed. Histologic evaluation revealed no evidence of recurrent disease. The patient did well and preformed self-catheterization of the continent conduit for the next 5 months until she was diagnosed with right hydronephrosis secondary to a ureteral stricture. A percutaneous nephrostomy tube was placed and changed at regular intervals. The right ureter remained stented for a total of 11 months. Eight months later the patient developed gross hematuria which was evaluated with a cystoscopy of the reservoir. The site of bleeding could not be identified due to limited visual-
INTRODUCTION Ureteroarterial fistula (UAF) has a reported mortality of nearly 40% [1, 2]. Risk factors associated with the development of ureteroarterial fistulas include pelvic malignancy, radiotherapy, vascular pathology, previous vascular or pelvic surgery, pregnancy, infection, and indwelling ureteral stents [1–3]. Prior genitourinary or pelvic surgery and ureteral stents are the most frequently cited, occurring in approximately twothirds of all cases. We report a case of a patient treated with primary radiation therapy for cervical cancer in which successful surgical therapy of a ureteral– external iliac arterial fistula was followed by a ureteral– common iliac arterial fistula, which resulted in acute exsangination and death. To our knowledge this is the first report of a recurrent UAF. 1 To whom correspondence and reprint requests should be addressed at the Affiliations Program in Woman’s Oncology, Woman and Infants Hospital, 101 Dudley Street, Providence, RI 02905-2499.
0090-8258/01 $35.00 Copyright © 2001 by Academic Press All rights of reproduction in any form reserved.
192
193
CASE REPORT
FIG. 1.
Angiogram of femoral–femoral bypass.
ization. When the bleeding necessitated multiple transfusions over an 8-day period, a laparotomy was performed. The conduit was taken down and opened and no bleeding site was identified within the reservoir. However, an approximately 7-mm right ureteral– external iliac artery fistula was identified. A vascular surgery consult was called. The external iliac artery was inspected and found to have significant radiation vasculitis; this in combination with the 7-mm defect led to the decision to ligate and bypass the external iliac artery. This was accomplished with a femoral–femoral arterial bypass. A new ileal conduit was constructed above the pelvic brim, the distal ureters were resected to allow ureteral–ileal anastomosis, and bilateral single-J ureteral stents were placed. Postoperatively no further bleeding occured, the femoral–femoral bypass (Fig. 1) remained patent, and the incontinent ilieal conduit functioned well. After doing well postoperatively, 6 months later she was found unconscious and hypotensive with her conduit appliance filled with blood. She was resuscitated with blood products and crystalloid, after which she underwent pelvic angiography. Angiogram revealed a right uretero– common iliac arterial fistula (Figs. 2, 3), which was sucessfully embolized (Fig. 4). Though the bleeding promptly subsided and her vital signs stabilized, neurologic evaluation revealed profound central nervous system insult. She had fixed dilated pupils with cortical posturing. She expired approximately 8 h later.
DISCUSSION There have been more than 35 cases of UAF reported in the world literature. All these patients had one or more specific risk factors that can theoretically contribute to UAF formation. Predisposing risk factors associated with the development of UAF include pelvic malignancy, radiotherapy, vascular pathology, previous vascular or pelvic surgery, pregnancy, surgical trauma, infection, and indwelling ureteral stents [1–3]. The most common malignancies associated with the development of UAF are either cervical or endometrial carcinomas [1]. Only five cases of UAF have been reported in patients following a pelvic exenteration as surgical treatment for cervical carcinoma [3, 4]. Anatomically most fistulas occur at the point where the ureter crosses the common iliac artery at the pelvic brim [3]. The precise pathophysiologic mechanism of fistula formation remains unknown. Tissue ischemia, inflammation, fibrosis, and ureteral obstruction may contribute to UAF development. However, many reported cases have associated UAF with the presence of a foreign body, either a vascular graft or a ureteral stent. The use of ureteral stents in managing ureteral obstruction or following urinary diverting procedures has become common practice in gynecologic oncology. Although recent modifications of ureteral stents have minimized short-term complica-
194
DEPASQUALE, MYLONAS, AND FALKENBERRY
FIG. 2.
Initial angiogram revealing recurrent fistula at the right common iliac to the right ureter.
tions, chronic use can be associated with increased infection rate and functional complications. Prolonged ureteral stent placement or catheterization is thought to be a major risk factor in the formation of UAF, especially after radiotherapy, prior pelvic surgery, or unrecognized iatrogenic injuries [5, 6, 9]. Theoretically, the pulsatile action of the artery against the stented ureter can cause pressure necrosis of both arterial and ureteral wall and therefore contribute to an UAF formation [4]. Prior radiotherapy is also an apparent risk factor for the formation of UAF. Fistula development can occur in an irradiated field due to effects on microcirculation and healing properties of the surrounding tissue [1, 8]. Surgery within a previously irradiated field can also increase the risk for ureteral ischemia, scar formation, and fibrosis that could result in a UAF formation. Preexisting vascular surgery may also predispose to the formation of UAF [1, 7]. During vascular surgery the segmental blood supply to the ureter is sometimes compromised and there is often minimal intervening tissue between the ureter and the bypass graft. The ureter may become fixed and obstructed by an inflammatory process surrounding the prosthetic graft [7]. Due to the extreme infrequency of UAF, it is usually not considered high on the differential diagnosis for urinary tract bleeding following treatment of a gynecologic malignancy. More common etiologies are urinary infection, radiation necrosis, urinary tract lithiasis, and recurrent malignancy. Even
when suspected, there are difficulties in demonstrating fistulas by radiographic means. An antegrade and retrograde urogram or selective arteriogram may be initially negative in the absence of active bleeding. Previous case reports have demonstrated that provocative arteriograms, which entail manipulating the ureter during the angiogram, will often allow visualization of the fistula [1]. Routine studies for hematuria such as an intravenous pyelogram and cystoscopy rarely provide evidence of the UAF. A full radiographic evaluation, including arteriography, is necessary in stable patients to rule out other pathologic etiologies and also provide additional information necessary for a subsequent arterial reconstruction. The placement of an angioplasty balloon catheter may also be useful in controlling bleeding while definite therapeutic steps are taken. Angiographic occlusion of the involved vessels to allow stabilization of the clinical condition is sometimes required, followed by operative revascularization [3, 4]. A convenient and effective expedient is the extraanatomic arterial reconstruction, usually with a femoral–femoral bypass [1]. Primary repair of the vessel or the use of graft material for reconstruction has also been reported [6]. The most commonly used interventions are nephrectomy and ureteral ligation [2, 5], while autotransplantation, renal irradiation, and renal embolization have been tried [9]. Retrieval of a functional renal unit is a major priority and kidney function can be preserved after the arterial component of the fistula is eliminated and ureteral patency is reestablished.
CASE REPORT
FIG. 3.
Angiogram of ureteroarterial fistula, with extravasation of blood into the ileal– colonic conduit.
Our patient, during treatment of her advanced cervical carcinoma, underwent radiotherapy and surgery, including pelvic exenteration and ureteral stent placements. These therapeutic
FIG. 4.
195
Successful embolization of right common iliac artery.
measures, in addition to her malignancy, chemotherapy, and poor nutritional status, may have contributed to the development of the first UAF. The formation of a second fistula may have resulted from radiation vasculitis and postoperative fibrosis. To our knowledge this is the first report of a patient with recurrent UAF. Although UAF is rare, measures to prevent its formation should be taken. Chronic ureteral stenting should always be done with the softest stents available and every effort should be made to remove the stent as soon as possible [8]. Intraoperative steps to avoid direct contact of the stented ureter and iliac artery may theoretically reduce the risk of fistula formation. This could be achieved by positioning, when possible, an omental flap between the vessels and ureter, placing the conduit above the iliac vessels, or tunneling the contralateral ureter through the small bowel mesentery [1, 3]. UAF is a rare complication associated with significant morbidity and mortality. Prior pelvic surgery, pelvic radiotherapy, and long-term ureteral stents are the most common factors contributing to the development of UAF. Because conventional tests such as intravenous pyelogram and cystoscopy are often unrevealing, the highest likelihood of diagnosing a UAF results from an appropiate level of suspicion in the presence of hematuria and predisposing risk factors. While acute hemorrhage may be controlled with arterial embolization, vascular bypass of repair combined with ureteral reimplantation will usually be required.
196
DEPASQUALE, MYLONAS, AND FALKENBERRY
REFERENCES 1. Batter SJ, McGovern FJ, Cambria RP. Ureteroarterial fistula: case report and review of the literature. Urology 1996;48:481–9. 2. Vandersteen DR, Saxon RR, Fuchs E, Keller FS, Taylor LM Jr, Barry JM. Diagnosis and management of ureteroiliac artery fistula: value of provocative arteriography followed by common iliac artery embolization and extra anatomic arterial bypass grafting. J Urol 1997;158: 754 – 8. 3. Gelder MS, Alvarez RD, Partridge EE. Ureteroarterial fistulae in exenteration patients with indwelling ureteral stents. Gynecol Oncol 1993;50:365– 70.
4. Toolin E, Pollack HM, McLean GK, Banner MP, Wein AJ. Ureteroarterial fistula: a case report. J Urol 1984;132:553– 4. 5. Cass AS, Odland M. Ureteroarterial fistula: case report and review of literature. J Urol 1990;143:582–3. 6. Smith RB. Ureteral common iliac artery fistula: a complication of internal double-J ureteral stent. J Urol 1984;132:113. 7. Schapira HE, Li R, Gribetz M, Wulfsohn MA, Brendler H. Ureteral injuries during vascular surgery. J Urol 1981;125:293–7. 8. Puppo P, Perachino M, Ricciotti G, Zinicola N, Patrone PE. Ureteroarterial fistula: a case report. J Urol 1992;148:863– 4. 9. Keller FS, Barton RE, Routh WD, Gross GM. Gross hematuria in two patients with ureteral–ileal conduits and double-J stents. J Vasc Interv Radiol 1990;1:69 –77.
CASE REPORT Fatal Recurrent Ureteroarterial Fistulas after Exenteration for Cervical Cancer S. E. DePasquale, M.D.,* ,1 I. Mylonas,* ,† and S. S. Falkenberry, M.D.* *Brown University School of Medicine and Affiliations Program in Woman’s Oncology, Woman and Infants Hospital, Providence, Rhode Island 02905-2499; and †Medical Faculty, University of Rostock, 18055 Rostock, Germany Received December 27, 2000; published online May 31, 2001
CASE REPORT
Background. Ureteroarterial fistula (UAF) is a rare occurrence. It can be difficult to diagnose with a high mortality. We report a case of a recurrent UAF. Case. A 38-year-old women diagnosed with cervical cancer had undergone pelvic exenteration for severe radiation-induced necrosis with a vesicovaginal and rectovaginal fistula after primary radiation therapy. Hemorrhage into the urinary tract necessitated surgical intervention and vascular repair with a femoral–femoral bypass. Although these measures were effective, the patient died 6 months later following an acute hemorrhage into her conduit. Arteriogram revealed a second UAF. Conclusion. When urinary tract bleeding occurs in patients previously diagnosed with a gynecologic malignancy and treated with radiation therapy and extensive surgery with urinary diversion, UAF should be considered in the differential diagnoses. © 2001 Academic Press
A 38-year-old woman was initially evaluated by the Gynecological Oncology Service and found to have a FIGO stage IIIb squamous cell carcinoma of the cervix with left hydronephrosis in November 1995. A CT scan was significant for a large left adnexal mass, an enlarged uterus, and left hydronephrosis and hydroureter. She underwent examination under anesthesia and was diagnosed with a stage IIIb squamous carcinoma of the cervix. A left percutaneous nephrostomy tube was placed after cystoscopic retrograde ureteral stent placement was unsuccessful due to extrinsic tumor compression. That same month she underwent pretreatment staging, with an exploratory laparotomy revealing negative paraaortic lymph nodes and left salpingo-oophorectomy with positive findings of squamous cell carcinoma on the left oviduct. She then received 4500 cGy radiation therapy to the pelvis using a four-field technique and 2440 cGy to point A with two Fletcher implants. The parametrial tissue received a 720-cGy boost using a AP/PA technique. She also received six weekly cycles of cisplatin chemotherapy (40 mg/m 2) as a radiosensitizer. Ten months later, large rectovaginal and vesicovaginal fistulas were diagnosed. Clinical and radiographic evaluation revealed extensive tissue necrosis and radiation fibrosis with no evidence of recurrent disease. After failure of conservative measures including bowel rest with hyperalimentation, a total pelvic exenteration with formation of a continent ileal– colonic conduit was performed. Histologic evaluation revealed no evidence of recurrent disease. The patient did well and preformed self-catheterization of the continent conduit for the next 5 months until she was diagnosed with right hydronephrosis secondary to a ureteral stricture. A percutaneous nephrostomy tube was placed and changed at regular intervals. The right ureter remained stented for a total of 11 months. Eight months later the patient developed gross hematuria which was evaluated with a cystoscopy of the reservoir. The site of bleeding could not be identified due to limited visual-
INTRODUCTION Ureteroarterial fistula (UAF) has a reported mortality of nearly 40% [1, 2]. Risk factors associated with the development of ureteroarterial fistulas include pelvic malignancy, radiotherapy, vascular pathology, previous vascular or pelvic surgery, pregnancy, infection, and indwelling ureteral stents [1–3]. Prior genitourinary or pelvic surgery and ureteral stents are the most frequently cited, occurring in approximately twothirds of all cases. We report a case of a patient treated with primary radiation therapy for cervical cancer in which successful surgical therapy of a ureteral– external iliac arterial fistula was followed by a ureteral– common iliac arterial fistula, which resulted in acute exsangination and death. To our knowledge this is the first report of a recurrent UAF. 1 To whom correspondence and reprint requests should be addressed at the Affiliations Program in Woman’s Oncology, Woman and Infants Hospital, 101 Dudley Street, Providence, RI 02905-2499.
0090-8258/01 $35.00 Copyright © 2001 by Academic Press All rights of reproduction in any form reserved.
192
193
CASE REPORT
FIG. 1.
Angiogram of femoral–femoral bypass.
ization. When the bleeding necessitated multiple transfusions over an 8-day period, a laparotomy was performed. The conduit was taken down and opened and no bleeding site was identified within the reservoir. However, an approximately 7-mm right ureteral– external iliac artery fistula was identified. A vascular surgery consult was called. The external iliac artery was inspected and found to have significant radiation vasculitis; this in combination with the 7-mm defect led to the decision to ligate and bypass the external iliac artery. This was accomplished with a femoral–femoral arterial bypass. A new ileal conduit was constructed above the pelvic brim, the distal ureters were resected to allow ureteral–ileal anastomosis, and bilateral single-J ureteral stents were placed. Postoperatively no further bleeding occured, the femoral–femoral bypass (Fig. 1) remained patent, and the incontinent ilieal conduit functioned well. After doing well postoperatively, 6 months later she was found unconscious and hypotensive with her conduit appliance filled with blood. She was resuscitated with blood products and crystalloid, after which she underwent pelvic angiography. Angiogram revealed a right uretero– common iliac arterial fistula (Figs. 2, 3), which was sucessfully embolized (Fig. 4). Though the bleeding promptly subsided and her vital signs stabilized, neurologic evaluation revealed profound central nervous system insult. She had fixed dilated pupils with cortical posturing. She expired approximately 8 h later.
DISCUSSION There have been more than 35 cases of UAF reported in the world literature. All these patients had one or more specific risk factors that can theoretically contribute to UAF formation. Predisposing risk factors associated with the development of UAF include pelvic malignancy, radiotherapy, vascular pathology, previous vascular or pelvic surgery, pregnancy, surgical trauma, infection, and indwelling ureteral stents [1–3]. The most common malignancies associated with the development of UAF are either cervical or endometrial carcinomas [1]. Only five cases of UAF have been reported in patients following a pelvic exenteration as surgical treatment for cervical carcinoma [3, 4]. Anatomically most fistulas occur at the point where the ureter crosses the common iliac artery at the pelvic brim [3]. The precise pathophysiologic mechanism of fistula formation remains unknown. Tissue ischemia, inflammation, fibrosis, and ureteral obstruction may contribute to UAF development. However, many reported cases have associated UAF with the presence of a foreign body, either a vascular graft or a ureteral stent. The use of ureteral stents in managing ureteral obstruction or following urinary diverting procedures has become common practice in gynecologic oncology. Although recent modifications of ureteral stents have minimized short-term complica-
194
DEPASQUALE, MYLONAS, AND FALKENBERRY
FIG. 2.
Initial angiogram revealing recurrent fistula at the right common iliac to the right ureter.
tions, chronic use can be associated with increased infection rate and functional complications. Prolonged ureteral stent placement or catheterization is thought to be a major risk factor in the formation of UAF, especially after radiotherapy, prior pelvic surgery, or unrecognized iatrogenic injuries [5, 6, 9]. Theoretically, the pulsatile action of the artery against the stented ureter can cause pressure necrosis of both arterial and ureteral wall and therefore contribute to an UAF formation [4]. Prior radiotherapy is also an apparent risk factor for the formation of UAF. Fistula development can occur in an irradiated field due to effects on microcirculation and healing properties of the surrounding tissue [1, 8]. Surgery within a previously irradiated field can also increase the risk for ureteral ischemia, scar formation, and fibrosis that could result in a UAF formation. Preexisting vascular surgery may also predispose to the formation of UAF [1, 7]. During vascular surgery the segmental blood supply to the ureter is sometimes compromised and there is often minimal intervening tissue between the ureter and the bypass graft. The ureter may become fixed and obstructed by an inflammatory process surrounding the prosthetic graft [7]. Due to the extreme infrequency of UAF, it is usually not considered high on the differential diagnosis for urinary tract bleeding following treatment of a gynecologic malignancy. More common etiologies are urinary infection, radiation necrosis, urinary tract lithiasis, and recurrent malignancy. Even
when suspected, there are difficulties in demonstrating fistulas by radiographic means. An antegrade and retrograde urogram or selective arteriogram may be initially negative in the absence of active bleeding. Previous case reports have demonstrated that provocative arteriograms, which entail manipulating the ureter during the angiogram, will often allow visualization of the fistula [1]. Routine studies for hematuria such as an intravenous pyelogram and cystoscopy rarely provide evidence of the UAF. A full radiographic evaluation, including arteriography, is necessary in stable patients to rule out other pathologic etiologies and also provide additional information necessary for a subsequent arterial reconstruction. The placement of an angioplasty balloon catheter may also be useful in controlling bleeding while definite therapeutic steps are taken. Angiographic occlusion of the involved vessels to allow stabilization of the clinical condition is sometimes required, followed by operative revascularization [3, 4]. A convenient and effective expedient is the extraanatomic arterial reconstruction, usually with a femoral–femoral bypass [1]. Primary repair of the vessel or the use of graft material for reconstruction has also been reported [6]. The most commonly used interventions are nephrectomy and ureteral ligation [2, 5], while autotransplantation, renal irradiation, and renal embolization have been tried [9]. Retrieval of a functional renal unit is a major priority and kidney function can be preserved after the arterial component of the fistula is eliminated and ureteral patency is reestablished.
CASE REPORT
FIG. 3.
Angiogram of ureteroarterial fistula, with extravasation of blood into the ileal– colonic conduit.
Our patient, during treatment of her advanced cervical carcinoma, underwent radiotherapy and surgery, including pelvic exenteration and ureteral stent placements. These therapeutic
FIG. 4.
195
Successful embolization of right common iliac artery.
measures, in addition to her malignancy, chemotherapy, and poor nutritional status, may have contributed to the development of the first UAF. The formation of a second fistula may have resulted from radiation vasculitis and postoperative fibrosis. To our knowledge this is the first report of a patient with recurrent UAF. Although UAF is rare, measures to prevent its formation should be taken. Chronic ureteral stenting should always be done with the softest stents available and every effort should be made to remove the stent as soon as possible [8]. Intraoperative steps to avoid direct contact of the stented ureter and iliac artery may theoretically reduce the risk of fistula formation. This could be achieved by positioning, when possible, an omental flap between the vessels and ureter, placing the conduit above the iliac vessels, or tunneling the contralateral ureter through the small bowel mesentery [1, 3]. UAF is a rare complication associated with significant morbidity and mortality. Prior pelvic surgery, pelvic radiotherapy, and long-term ureteral stents are the most common factors contributing to the development of UAF. Because conventional tests such as intravenous pyelogram and cystoscopy are often unrevealing, the highest likelihood of diagnosing a UAF results from an appropiate level of suspicion in the presence of hematuria and predisposing risk factors. While acute hemorrhage may be controlled with arterial embolization, vascular bypass of repair combined with ureteral reimplantation will usually be required.
196
DEPASQUALE, MYLONAS, AND FALKENBERRY
REFERENCES 1. Batter SJ, McGovern FJ, Cambria RP. Ureteroarterial fistula: case report and review of the literature. Urology 1996;48:481–9. 2. Vandersteen DR, Saxon RR, Fuchs E, Keller FS, Taylor LM Jr, Barry JM. Diagnosis and management of ureteroiliac artery fistula: value of provocative arteriography followed by common iliac artery embolization and extra anatomic arterial bypass grafting. J Urol 1997;158: 754 – 8. 3. Gelder MS, Alvarez RD, Partridge EE. Ureteroarterial fistulae in exenteration patients with indwelling ureteral stents. Gynecol Oncol 1993;50:365– 70.
4. Toolin E, Pollack HM, McLean GK, Banner MP, Wein AJ. Ureteroarterial fistula: a case report. J Urol 1984;132:553– 4. 5. Cass AS, Odland M. Ureteroarterial fistula: case report and review of literature. J Urol 1990;143:582–3. 6. Smith RB. Ureteral common iliac artery fistula: a complication of internal double-J ureteral stent. J Urol 1984;132:113. 7. Schapira HE, Li R, Gribetz M, Wulfsohn MA, Brendler H. Ureteral injuries during vascular surgery. J Urol 1981;125:293–7. 8. Puppo P, Perachino M, Ricciotti G, Zinicola N, Patrone PE. Ureteroarterial fistula: a case report. J Urol 1992;148:863– 4. 9. Keller FS, Barton RE, Routh WD, Gross GM. Gross hematuria in two patients with ureteral–ileal conduits and double-J stents. J Vasc Interv Radiol 1990;1:69 –77.