Molly E. DeWitt-Foy, MD

“Challenging Cases in Urology” is a new Urology Times section in which residents from the nation’s leading urology programs present their toughest cases and how they ultimately managed them. Cases inform readers of the problem-solving process and provide a lesson from the authors’ experience.

A 57-year-old man initially presents to a general surgeon with a chief complaint of right lower back and posterior neck pain, with associated soft tissue swelling. Eight months prior to referral to our institution, he underwent excision of these lesions, pathology of which showed benign lipomas. On presentation to our institution, he had experienced regrowth of the masses with "ticking" in the right lumbar area that he correlated with his heartbeat. He also reported unintentional weight loss of 15 pounds over the previous 3 months.

The patient’s past medical history was notable for hypertension, well controlled on oral medications, and glaucoma. Surgical history was remarkable for surgical excision of lipomas as noted above, and open reduction and internal fixation of a right elbow and wrist fracture. Family history revealed stomach cancer in his father, liver cancer in his mother, and no notable medical problems in his younger sister.

Challenging case: Persistent hemorrhage following ureteral stent exchange

He had a very brief and remote history of smoking, used alcohol rarely, and at the time of initial office visit was still actively working as a mechanical engineer.

On physical exam he was well nourished with a BMI of 29 kg/m

, alert and oriented to person, time, and place. He rated his pain at a 7/10 on the right buttock and was unable to lie down for the exam because of this pain. His abdomen was soft, nontender, and without scars. Peripheral pulses were 2+ and there was no appreciable groin lymphadenopathy. He had a very large right lumbar and gluteal mass that was firm but did not show signs of skin involvement. There was an appreciable bruit on auscultation.

The upper mid portion had a well-healed 5-cm transverse incision. Extremities had no edema or cyanosis, with mildly decreased strength of his right leg.

Laboratory analysis showed a normal complete blood count with a hemoglobin of 14, white blood cell count of 8, and platelet count of 229. Complete metabolic panel was notable for hypercalcemia with serum Ca 11.7 mg/dL; renal function was normal with creatinine of 0.74. A coagulation panel was normal, as were urinalysis and liver function tests.

Challenging case: A young woman presenting with rapid weight gain

A contrast-enhanced MRI of the pelvis showed a 13 cm by 12 cm mass centered on the right gluteal region with extensive osseous and soft tissue involvement concerning for a malignant neoplasm. Specifically, the mass invaded the right iliac bone, right iliopsoas, gluteus medius and maximus, and S1-3 sacral foramina. The right gluteal arteries appeared enlarged.

Chest and abdomen CTs with intravenous contrast were subsequently ordered. CT chest showed multiple pulmonary nodules bilaterally and a large, expansile lytic lesion of the left scapula, all concerning for metastatic disease. CT abdomen demonstrated a 4-cm solid enhancing mass in the upper pole of the left kidney, abutting the renal sinus, without associated hydronephrosis (figure). Hydronephrosis and hydroureter were noted down to the pelvis on the rightside to the level of a 3x2-cm mass in the lateral upper right pelvis.

Contrast-enhanced commuted tomography, coronal section, demonstrating 4-cm renal mass in the left upper pole, dilation of the left collecting system, and large invasive right gluteal mass. (Photo courtesy of Molly E. DeWitt-Foy, MD, Kyle J. Ericson, MD, and Venkatesh Krishnamurthi, MD)

On further chart review, one prior non-contrast abdominal CT scan was identified from 12 years earlier; this identified no renal masses. An MRI brain was negative for intracranial metastasis.

The patient underwent Tru-Cut needle biopsy of the right gluteal mass. Pathologic analysis was consistent with metastatic renal cell carcinoma, clear cell type.

Given the right-sided hydronephrosis, the decision was made to take the patient for cystoscopy and right ureteral stent placement. Cytoreductive nephrectomy was considered, but due to the extensive degree of metastatic disease and small primary tumor burden, non-operative management was favored.

Challenging case: CT indicates germ cell tumor, but no palpable testicular mass present

The patient was referred to medical oncology and elected to enroll in a clinical trial. He initially received immunotherapy with an anti-PDL1 antibody alone (atezolizumab [Tecentriq]), but due to progressive disease he crossed over to receive a combination of atezolizumab and bevacizumab (Avastin). He again progressed and ultimately was treated with axitinib (Inlyta), a small molecule tyrosine kinase inhibitor. Three years later his disease remains stable and he undergoes regular stent exchanges to manage his obstructed right renal unit.

Detection of small renal masses, measuring ≤4 cm, has increased significantly over the last 3 decades, largely due to the increase in cross-sectional abdominal imaging done for other purposes. Despite earlier detection and treatment of renal masses, the mortality for kidney cancer patients has not improved 

 This may be indicative of biologic heterogeneity of these tumors, which is currently poorly understood.

Meta-analyses suggest 20% of small renal masses are benign, 60% display indolent growth behavior, and 20% are aggressive malignancies. Most small renal masses exhibit slow growth and up to 30% may not grow at all during a period of active surveillance. Indeed, the risk of metastatic disease for a small renal mass is less than 2% 

Challenging case: Persistent ureteral stone in a 76-year-old male

Here we present a patient who was found to have a small renal mass only after presenting with large-volume diffuse metastatic disease to the contralateral gluteal region causing obstructive uropathy of the unaffected kidney. Two biopsies were required to achieve accurate pathologic diagnosis. He was managed with an immune checkpoint inhibitor and targeted molecular therapy, as well as regular right ureteral stent exchanges.

Although cytoreductive nephrectomy can certainly be used in metastatic renal cell carcinoma, careful patient selection for debulking is essential. A number of studies have aimed to answer this question, and most would argue that patients with poor performance status and/or intracranial metastasis are unlikely to benefit from surgery 

 Indeed, in the recently published randomized CARMENA trial, sunitinib alone was non-inferior to cytoreductive nephrectomy in intermediate- and poor-risk patients 

 In addition, in order for debulking to be most useful, nephrectomy should remove at least 75% of total tumor volume 

For this patient, his primary tumor was significantly smaller than his metastatic burden, and partial or radical nephrectomy would be unlikely to change his response to chemotherapy or affect his overall survival. The chronic obstruction of this patient's contralateral renal unit is another important consideration; an unnecessary nephrectomy would put him at risk of renal insufficiency and limit his ability to receive chemotherapy.

 is a staff physician at the Cleveland Clinic Glickman Urological & Kidney Institute, Cleveland.

Articles

The authors discuss the case of a 57-year-old man who initially presents to a general surgeon with a chief complaint of right lower back and posterior neck pain, with associated soft tissue swelling. On presentation to the authors' institution, he had experienced regrowth of the masses with "ticking" in the right lumbar area that he correlated with his heartbeat. He also reported unintentional weight loss of 15 pounds over the previous 3 months.

Challenging case: A large ‘ticking’ back lipoma and a small renal mass

A 69-year-old woman was transferred from an outside institution to our inpatient service with recurrent gross hematuria. Two weeks prior to transfer, she underwent routine bilateral ureteral stent exchange, which was complicated by gross hematuria with significant clot burden. Over the course of 10 days, she continued to have intermittent hematuria requiring continuous bladder irrigation with associated blood loss anemia necessitating transfusion with 4 units of packed red blood cells (RBCs).

Prior to transfer to our institution, cystoscopy demonstrated slow oozing from the left ureteral orifice, which became brisk upon removal of the left ureteral stent. A retrograde pyelogram revealed a normal-caliber ureter and renal pelvis without filling defects or extravasation. The stent was replaced, which reduced the bloody efflux. At this point a CT without contrast was obtained, which revealed no significant upper tract lesions or abnormalities. The patient was offered a left nephroureterectomy. However, her family desired a second opinion, which prompted transfer to our hospital.

The patient reported no prior episodes of gross hematuria and her previous stent exchanges were uneventful. Additionally, she did not report any flank pain, flank mass, weight loss, voiding symptoms, fevers, or chills. Despite requiring multiple transfusions, she reported no dyspnea, chest pain, or light-headedness.

Her medical history is notable for colon cancer treated by sigmoidectomy in 1995, endometrial cancer, and stage III chronic kidney disease presumably due to ureteral obstruction. In 2009, her endometrial cancer was treated with a total abdominal hysterectomy and bilateral salpingo-oophorectomy (TAH+BSO) followed by pelvic external beam radiation. In 2011, she required a small bowel resection for radiation enteritis. In 2012, she was noted to have bilateral hydroureteronephrosis and an atrophic left kidney, which has been managed with chronic indwelling double-J ureteral stents that are exchanged every 4 months.

She is a retired secretary who has an occasional glass of wine and has never smoked. Her mother was diagnosed with uterine cancer, but her family history was otherwise unremarkable.

On exam, our patient was a thin woman who appeared older than her stated age of 69 years. She was hemodynamically stable and a cardiopulmonary exam was unremarkable. Her abdomen was soft without flank masses or tenderness. Midline scars from her prior TAH+BSO, sigmoidectomy, and small bowel resection were noted. Her urine was light pink without clots on slow saline irrigation. Her exam was otherwise unremarkable.

Laboratory workup revealed an eGFR of 44 mL/min and a hemoglobin of 9.4 g/dL. Urinalysis showed gross blood without evidence of infection. A coagulation panel was negative and she was cross-matched for blood.

Vascular surgery and interventional radiology (IR) were consulted to develop a multidisciplinary approach. The patient was given IV hydration and a CT angiogram was obtained (figure 1), which noted no evidence of uretero-arterial fistula, no concerning upper tract or pelvic masses, and well-positioned stents bilaterally.

 CT angiogram, axial cut showing the left ureter and stent crossing over the external and internal iliac arteries close to the bifurcation. No communication can be seen.

After further discussion, we proceeded to the IR suite for an angiogram. The urology team was present with the patient positioned in “frog-leg” position, prepped, and draped in the event the ureteral stent would need to be removed over a wire to provoke bleeding. Several units of blood were immediately available. Angiography revealed a fistulous connection between the left pelvic ureter and the internal iliac artery (figure 2). The internal iliac artery was embolized with coils and a vascular plug (figure 3).

 Angiography showing opacification of the left internal iliac artery with antegrade and retrograde flow of contrast into the ureter.

 Angiography of the common iliac artery bifurcation after endovascular embolization of the internal iliac artery. Contrast is no longer seen in the ureter.

During the procedure, she experienced pelvic pressure concerning for bladder filling and voided a moderate volume of clot. She became hypotensive at this time, but improved significantly following embolization and transfusion of a unit of RBCs.

The patient’s hematuria resolved completely by day one after embolization. A percutaneous nephrostomy tube was placed to manage her chronically obstructed left kidney and she was discharged home without a urethral catheter on post-procedure day 2. Her left ureteral stent was removed as an outpatient 2 weeks after discharge.

Uretero-arterial fistulas are uncommon and require a high index of suspicion-and occasionally multiple imaging studies-to diagnose. Our patient underwent a non-contrast CT, retrograde pyelogram, and CT angiogram before her fistula was diagnosed and treated. While data on uretero-arterial fistulas are limited to small retrospective studies, prior series suggest 78% are missed on initial workup 

 IR angiography is the gold standard for diagnosis with a sensitivity of 60% to 100% when combined with ureteral stent manipulation 

 In comparison, CT angiography and retrograde pyelograms miss 60% and 50% of fistulas, respectively 

Our patient’s presentation and risk factors are consistent with the existing literature. The most common presentation is intermittent hematuria that may be exacerbated by stent exchange and often requires blood transfusion. Multiple risk factors are typically present and include prior pelvic surgery (89% of cases), chronic indwelling ureteral stents (67%), pelvic radiation (43%), prior vascular surgery, malignancy, and intrinsic vascular abnormalities (15%) 

Historically, treatment of uretero-arterial fistulas was surgical, which was often complex and morbid due to the frequent incidence of prior surgery and radiation. The development of endovascular technologies has shifted management to the IR suite. The most common sites of fistulization include the common iliac, internal iliac, and external iliac arteries. In patients with urinary diversion, uretero-aortic fistulas may occur 

Endovascular treatment is dictated by the location of the fistula; common iliac and external iliac fistulas can be treated with a covered stent graft, while fistulas to the internal iliac artery can be embolized. If a covered stent is used and traverses the internal iliac artery, the internal iliac should be embolized to prevent an endoleak. In our patient, although surgical therapy in the form of nephroureterectomy was initially offered by an outside institution, she was ultimately successfully managed with IR embolization.

Uretero-arterial fistulas are uncommon and often present a diagnostic and therapeutic challenge. Successful management requires a high index of suspicion and a multidisciplinary approach. In our case, the patient underwent multiple imaging studies and received 4 units of RBCs before angiography ultimately revealed the diagnosis.

A 69-year-old woman was transferred from an outside institution to our inpatient service with recurrent gross hematuria. Two weeks prior to transfer, she underwent routine bilateral ureteral stent exchange, which was complicated by gross hematuria with significant clot burden.

Author | Molly E. DeWitt-Foy, MD

Articles

Challenging case: A large ‘ticking’ back lipoma and a small renal mass

Challenging case: Persistent hemorrhage following ureteral stent exchange