The axial images of the CT urograph, as well as the associated sagittal reformation, demonstrated a large filling defect in the right renal pelvis. The filling defect extended into and replaced most of the right renal pelvis, resulting in a mass effect and a relative delay in the kidney's enhancement during the nephrographic phase (Figures 2-3). The combination of this radiographic appearance with a history of painless hematuria and positive urine cytology was indicative of upper-tract urothelial carcinoma.
Upper-tract urothelial carcinoma refers to malignant changes of the urothelial cells lining the urinary tract from the renal calyces to the ureteral orifice. Upper urinary tract urothelial carcinomas are relatively uncommon, only accounting for about 5-7% of all renal tumors and about 5% of all urothelial tumors. It appears that the true incidence of upper-tract tumors is increasing as the population ages. Upper-tract cancer is typically seen at an older age than bladder cancer; it rarely presents before the age of 40 years, and it has an average age of presentation of 65 years. The incidence of upper-tract tumors is 10 cases per 100,000 population per year. The highest incidence, however, appears to occur in Balkan countries, where urothelial cancers represent 40% of all renal cancers. The likelihood of developing upper-tract tumors among men is about twice that of women. Whites have a 2:1 risk of developing upper-tract tumors when compared with blacks; however, data indicates that disease-specific annual mortality is greater in black men than in white men (7.4% versus 4.9%) and greater in women than in men (6.1% versus 4.4%). Proposed etiologies for developing upper-tract urothelial carcinoma are similar to that of bladder cancer and include environmental factors (cigarette smoking), occupational exposures (aniline dyes), and treatment with anti-inflammatory (phenacetin) or chemotherapy (cyclophosphamide, ifosfamide) agents. A familial association has been identified in patients with Balkan nephropathy, although an unidentified environmental trigger may be the underlying etiology in these cases.[1,2,4]
The most common presenting symptom or finding that leads to the diagnosis of upper-tract urothelial tumors is hematuria, which occurs in 56-98% of patients. The second most common symptom is flank pain, which occurs in 30% of cases. The pain may vary from a dull sensation resulting from gradual obstruction of the collecting system to an acute pain mimicking renal colic, believed to result from an acute obstruction by a thrombus. About 15% of patients are asymptomatic at presentation and are diagnosed incidentally by an imaging study performed for a different indication. Patients presenting with advanced disease may suffer from loss of appetite, weight loss, a flank or abdominal mass, and bone pain. Traditionally, intravenous pyelography (IVP) was used to diagnose upper-tract tumors; however, CT urography (CT with a delayed urographic phase) is now becoming the primary diagnostic modality. Using CT urography, the sensitivity for detecting upper-tract malignant disease has been reported to approach 100%, with a specificity of 60% and a negative predictive value of 100%. CT urography does, however, expose the patient to higher doses of radiation and requires intravenous administration of contrast material. Radiolucent filling defects, obstruction or incomplete filling of a part of the upper tract, and nonvisualization of the collecting system are the typical findings suggestive of an upper-tract tumor. Filling defects may represent stones, blood clots, external compression, or a fungus ball. Stones can be ruled out by detecting calcifications on renal ultrasonography or a noncontrast CT scan. The clinician should always asses the contralateral kidney for possible bilaterality and to determine its functioning.[1,2]
If the diagnosis remains in question or the treatment plan may be adjusted based on a ureteroscopic evaluation, endoscopy with or without biopsy should be performed. Ureteroscopy provides a valuable tool in the evaluation of upper-tract urothelial carcinoma. As a result of advancements in optics, flexible ureteroscopes and endoscopic equipment, visualization and sampling of the tumor have improved. The greatest prognostic factors in the management of upper-tract urothelial carcinoma are pathologic grade and stage. Histologic correlations of up to 90% have been established between the initial ureteroscopic biopsy and the final pathologic specimen; however, because of the small size of the biopsy specimen and the depth of tissue sampling, outcomes with tumor stage have not demonstrated such a strong correlation. In 40 urothelial tumors staged in one series, 45% of tumors thought to be pathologic Ta were upstaged to T1-T3 at the time of complete resection. Ureteroscopic biopsy cannot reliably predict tumor stage; therefore, a combination of tumor grade, endoscopic visual appearance of the tumor, and radiologic appearance are required for the best prediction of tumor stage.[1,2,4]
Because voided urine cytology is nonspecific, the usefulness of it is limited. Even when using selectively obtained ureteral cytologies, the diagnostic yield is still only 60% accurate. Improved diagnostic yield has been demonstrated with the use of saline washing or brush biopsy, with an approximate sensitivity of 90% and a specificity near 90%.[2]
The standard treatment for upper-tract urothelial carcinoma has been nephroureterectomy with excision of a cuff of bladder. Advancements in percutaneous and endoscopic techniques, however, have allowed more conservative nephron-sparing procedures for patients with solitary kidneys or those who are otherwise not ideal candidates for extirpative surgery. Considered the "gold standard", radical nephroureterectomy with resection of a bladder cuff is the treatment of choice for large, high-grade, single or multifocal, noninvasive or invasive renal pelvis or proximal ureter tumors. The risk for multifocality and a high incidence of ipsilateral recurrence following partial resection are the reasons for the preference of this radical approach. Several approaches may be used, including totally open, totally laparoscopic, or a combination of both (eg, laparoscopic nephroureterectomy combined with an open distal intramural ureteral resection).[1,2,3,4]
Patients with a solitary kidney, bilateral disease, renal failure, or significant comorbidities preventing a large abdominal surgery are candidates for endoscopic resection. An additional group of patients who may benefit from endoscopic treatment are those with a small, low-grade lesions in the presence of a normal contralateral kidney. Tumors located at the distal ureter may be treated with a rigid ureteroscope, whereas those situated in the upper-urinary tract may be reached by a flexible ureteroscope or by an antegrade percutaneous approach. Initially, biopsies are taken, and then ablation is achieved using electrocautery or laser energy. Historically, open nephron-sparing surgery for upper-tract urothelial carcinoma was used in patients with a large renal pelvis tumor in a solitary kidney or in cases of synchronous bilateral tumors. Advancements in endourologic techniques, particularly percutaneous antegrade renal surgery, have largely replaced this approach for the conservative management of renal pelvis tumors. Segmental (partial) ureteral resection with end-to-end anastomosis or bladder reimplantation is performed in cases with low-grade, noninvasive tumors of the proximal or mid ureter that cannot be managed endoscopically when nephron-sparing is crucial for the preservation of renal function.[1,2,4]
The recurrence pattern following treatment of upper-tract urothelial carcinoma may be divided into vesical and extravesical recurrence. The higher the grade and stage of the upper-tract urothelial carcinoma, the higher the risk for extravesical recurrence. The recommended follow-up for patients treated for upper-tract urothelial carcinoma should consist of periodic history and physical examination, urinary cytology, and surveillance cystoscopy (occurring every 3 months for the first 2 years after treatment, every 6 months for the next 2 years, and yearly thereafter if the patient is free from disease recurrence). In cases of high-grade urothelial carcinoma, radiographic studies, including chest radiography and abdominopelvic CT scanning, should be performed every 6 months for the first 2 years and then yearly thereafter. Ipsilateral endoscopy for patients who undergo organ-sparing treatment should occur every 6 months for the first 2-3 years and then yearly thereafter, provided that the patient is free of disease. Bone scans should only be performed if the patient has symptoms of bone pain or for an elevated alkaline phosphatase level.[1,4,5]
In this patient, a cystoscopy was performed upon admission which showed a normal bladder without any exophytic tumor. The combination of a large filling defect in the right renal pelvis seen on CT urography and positive urine cytology made the diagnosis of upper-tract urothelial carcinoma. The patient received a comprehensive explanation of the available treatment modalities and elected to undergo nephroureterectomy. The surgery involved a combined laparoscopic and open approach. The right kidney and ureter were removed entirely, including a bladder cuff around the right distal ureter. The postoperative phase was uneventful and the patient was discharged on the seventh postoperative day. She is now under surveillance after surgery, with no evidence of recurrence.
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