A 73-year-old male presented to Urology Specialists of the Lehigh Valley in October 2010 with a right renal pelvis filling defect, potentially a urothelial carcinoma. The lesion was detected by CT scan (Figure A) performed for unrelated reasons and had not been visible on prior CT scans.
The patient had smoked for 20
years but had stopped smoking approximately 10
years prior. He previously had non-small cell lung cancer that was treated with radiation and chemotherapy in 2001–2002 and was in remission. In 2001–2002 he had a coronary artery bypass graft and an abdominal aortic aneurysm repaired. The patient was asymptomatic from these conditions at the time of presentation.
A physical examination was normal. The laboratory values were within normal limits. The patient had no urinary complaints. Urine cytology and cystoscopy were negative. Right retrograde pyelogram disclosed a complete ureteral duplication. Complete ureteropyeloscopy was not possible due to the narrow ureters. Retrograde pyelogram of the lower pole was performed and was normal. It was not possible to perform a retrograde pyelogram of the upper pole unit because the ureter was only about 1
mm in diameter, where a normal ureter is 3–4
mm in diameter. The instruments used in our practice are sized and scaled for a normal ureter and not for this small ancillary ureter. An attempted pyelogram was unsuccessful as the contrast did not fill the ureter or renal pelvis.
Approximately 6-months following initial urological evaluation, CT scan confirmed the presence of the mass which now appeared larger (Figure B). These findings were consistent with urothelial carcinoma of the renal pelvis, although urine cytology was again negative.
Prior to initiating more invasive diagnostic methods, a real-time PCR-based genetic assay was used to determine if the patient’s urine contained DNA that carried
FGFR3 mutations in exons 7, 10, or 15 [
13]. This assay has 99.9% specificity for urothelial carcinoma. A mutation was detected in exon 10 (Y375C) of
FGFR3, indicating a high probability (94.7% PPV) that the patient had urothelial carcinoma.
The patient underwent right nephroureterectomy. The arterial anatomy precluded an upper pole nephroureterectomy. The tumor involved the renal pelvis of the upper pole collecting system. Upon cut sections, the kidney exhibited an ill-defined partially raised, partially nodular tan-pink dense focus, located in the renal pelvis of the upper pole, which measured 1.5
cm greatest dimension. This focal area appeared limited to the upper pole renal pelvis/calyx and abutted but did not involve kidney parenchyma or peripelvic fat. Due to autolysis, tumor grade was somewhat difficult to provide definitively. However, the pathologist favored a designation of low grade urothelial carcinoma (WHO 2004). No lamina propria, renal parenchyma or peri-nephric fat involvement was identified such that the tumor stage was Ta,N0,M0. Tumor tissue obtained from the archival paraffin block was found, using quantitative PCR, to have an exon 10 (Y375C) mutation, which is consistent with the tumor being the source of the mutant DNA found in the urine.
Since the nephroureterectomy, the patient has been monitored for recurrent cancer. We performed a postoperative CertNDx test in March 2012, 7
months after the nephroureterectomy, which was negative for the presence of
FGFR3 mutant DNA. In addition following the uncomplicated postoperative course, the patient had surveillance cystoscopies in November 2011 and February 2012, both of which were negative. As part of the continuing follow-up, the patient will undergo surveillance cystoscopy several times per year for the foreseeable future. In view of the negative CertNDx test, upper tract imaging has not yet been performed. The left kidney has not been examined as it was normal at the time of the most recent CT scan (June 2011).
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