Initial clinical experience with use of ureteral access sheaths in the diagnosis and treatment of upper tract urothelial carcinoma

Diagnostic accuracy of upper tract urothelial carcinoma using biopsy, urinary cytology, and nephroureterectomy specimens: A tertiary cancer center experience

OBJECTIVES

We studied the diagnostic accuracy and discordance of upper tract urothelial carcinoma (UTUC) by comparing biopsy and urinary cytology with matched nephroureterectomy specimens.

METHODS

Sixty-nine patients with UTUC without neoadjuvant treatment were retrospectively identified who had matched biopsy and nephroureterectomy specimens. Twenty patients had concurrent upper tract cytology. H&E and cytology slides were re-reviewed. Statistical analysis was performed.

RESULTS

Patients included 48 men and 21 women with a mean age of 69 years. A concordant grade between biopsy and surgical specimen was present in 49 (71%) patients. The mean size of biopsy specimens in the discordant group was significantly smaller than that in the concordant group. Invasion was evaluated in 48 biopsy cases that had adequate subepithelial tissue, and 33 of them were diagnosed with concordant invasion status. Mean tumor size in both tumor grade and invasion discordant groups was significantly larger than that in the concordant group. High-grade urothelial carcinoma was detected in 84% of cases using urinary cytology.

CONCLUSIONS

Our study demonstrates the diagnostic challenges of UTUC on small biopsy specimens. Biopsy specimen size and tumor size are significantly associated with the diagnostic discordance. Upper tract cytology showed high diagnostic accuracy and should be complementary to the biopsy.

Diagnosing upper tract urothelial carcinoma: A review of the role of diagnostic ureteroscopy and novel developments over last two decades

Objective

The role of ureteroscopy in the diagnosis of upper tract urothelial carcinoma is yet to be fully determined. We aimed to provide an up to date evaluation of its role and the emerging technologies in the field.

Methods

A literature search of the last two decades (from 24th May, 2001 to 24th May, 2021) was carried out identifying 147 papers for potential inclusion within this narrative review.

Results

Diagnostic ureteroscopy is undeniably useful in its ability to visualise and biopsy indeterminate lesions, and to risk stratify malignant lesions that may be suitable for kidney sparing surgery. However, an increased risk of intravesical recurrence following nephroureterectomy when a prior diagnostic ureteroscopy has been performed, inadequate sampling at biopsy, complications from the procedure, and difficult ureteric access are all potential drawbacks. Furthermore, whilst generally an accurate diagnostic procedure, it risks missing carcinoma in-situ lesions. Despite this, evidence shows that routine use of ureteroscopy changes the management of patients in a large proportion of cases, preventing unnecessary surgery or facilitating kidney sparing surgery. The overall rate of complications is low, and improved biopsy techniques and the use of tissue biomarkers for improved staging and grading are encouraging. The risks of delays to definitive management and post-ureteroscopy intravesical recurrence do not seem to affect survival, and trials are in progress to determine whether intravesical therapy can mitigate the latter. Further promising techniques are being investigated to improve shortcomings, particularly in relation to improved diagnosis of carcinoma in situ and preoperative staging.

Conclusion

Ureteroscopy has a role in the diagnosis of upper tract malignancy, though whether it should be used routinely is yet to be determined.

Does ureteral access sheath have an impact on ureteral injury?

Objective:

To present a well-organized review about ureteral access sheath impact on ureteral injury.

Materials and Methods:

Systemic search on literature was done. Total of 3766 studies observed by two urologists and results were unified. A Prisma diagram was used for eliminating irrelevant studies and at the end of elimination process 28 studies were found eligible for this review.

Results:

Not only clinical studies but also comparative experimental animal studies show that there is no significant data to claim that ureteral access sheath insertion causes more ureteral injury. Pre-stented patients were found to be at lower risk for ureteral injury. Risk of progression to ureteral injury seems to be low even if ureteral injury occurs with insertion of ureteral access sheath.

Conclusion:

Summary of studies’ results indicate that use of ureteral access sheath doesn’t increase ureteral injury. This review may help understanding safety profile of ureteral access sheath on evidence-based level. There is not enough data to make a statement that ureteral access sheath prevents ureteral injury.

Bladder Recurrence Following Diagnostic Ureteroscopy in Patients Undergoing Nephroureterectomy for Upper Tract Urothelial Cancer: Is Ureteral Access Sheath Protective?

OBJECTIVES

To examine the effect of diagnostic ureteroscopy (URS) and ureteral access sheath usage on bladder recurrence following radical nephroureterectomy (RNU).

METHODS

We retrospectively reviewed the records of patients who underwent RNU between 2005-2019. Patients with a history of bladder cancer and those without a bladder cuff resection were excluded. Bladder recurrence was the primary outcome and cox regression modeling was used to assess the impact of URS adjusting for other factors.

RESULTS

Out of 271 RNU cases, 143 were included with a median age of 73 years (IQR 65-80). URS was performed in 104 cases (73%) and a ureteral access sheath was used in 26 (25%). With a median follow-up of 27 months, there were 36 (25%) bladder recurrences. The bladder recurrence rate (median time to recurrence) for patients who had URS vs. no URS was 30.8% (9.0 months) and 7.7% (12.1 months), respectively (p=0.02). A lower recurrence rate was noted in patients whom a ureteral access sheath was utilized (11.5%) vs. those with no access sheath (39.7%, p=0.01). Multivariable analysis revealed a significant increase in bladder recurrence if URS was performed prior to RNU (HR 5.6 [1.7-18.5], p<0.004), however, this effect was mitigated if a ureteral access sheath was used (HR 1.3, [0.3-6.4], p=0.76). Ureteral stent usage and performing a ureteroscopic biopsy had no significant effect on bladder recurrence.

CONCLUSION

Diagnostic URS in patients undergoing RNU for UTUC significantly increases the risk of bladder recurrence. This effect may be mitigated by using a ureteral access sheath.

Impact of ureteral access sheath on renal stone treatment: prospective comparative non-randomised outcomes over a 7-year period

PURPOSE

To compare the outcomes (stone free rate and complications) of renal stone treatment with and without the use of ureteral access sheath (UAS). The worldwide use of UAS has risen over the last decade; however, questions still remain on the safety and outcomes with its use. We wanted to look at the role of UAS for treatment of consecutive renal stones over a 7-year period.

METHODS

The outcomes of flexible ureteroscopy and stone treatment (FURS) for renal stones with and without the use of UAS was prospectively compared from March 2012 to July 2018. Patients were divided into two groups: group-1 where UAS was used for stone treatment and group-2 where a UAS was not used. Data were collected prospectively on consecutive patients for demographics, stone size, location and number, pre and post-operative stent usage, operative time duration, stone free rate (SFR), length of stay and complications.

RESULTS

During the study period, 338 patients underwent FURS for renal stones, of which a UAS was used for 203 (60%) patients. The mean age of patients was 56 years (range 2-89 years) with a male:female ratio of 204:134. The mean cumulative stone size and the mean number of stones was 16.5 ± 10.8 mm and 11.37 ± 8.08 mm (P < 0.001), and 2.17 ± 1.99 and 1.66 ± 1.50 (P = 0.009) for groups 1 and 2 respectively. The pre and post-operative stent insertion rates were similar in the two groups. The procedural time was longer in group-1 (54.8 ± 25.8 min) compared to group-2 (41.3 ± 22.2 min) (P < 0.001). The SFR for group-1 (88%) was slightly lower than group-2 (94%) although this was not statistically significant (P = 0.07). There were no intra-operative complications in either of the groups. Post-operative complications were seen in eight patients in group-1 (7 Clavien I/II and 1 Clavien IVa) and two patients in group-2 (Clavien I) (P = 0.19).

CONCLUSION

The use of UAS for renal stones is safe with no intra-operative complications noted in our series. Good stone-free rates were obtained for large and multiple renal stones with a small risk of minor complications post-operatively.

Thulium-laser retrograde intra renal ablation of upper urinary tract transitional cell carcinoma: an ESUT Study

BACKGROUND

Radical nephroureterectomy (RNU) is the gold standard treatment for upper urinary tract urothelial carcinoma (UTUC); however, patients presenting with small low-grade UTUC have been treated by flexible ureteroscopic laser ablation with good outcomes. Different types of laser have been discussed in the literature including Holmium and Neodymium lasers. We aimed to assess the safety and efficacy of Thulium laser (Tm:YAG) in the ureteroscopic ablation of UTUC.

METHODS

A retrospective observational multicentre study of patients diagnosed with papillary UTUC between January 2015 and December 2016 was carried out. All patients underwent ureteroscopic biopsy of the UTUC followed by Tm:YAG ablation. Based on the histopathological grade of the tumor, patients were counseled to undergo either RNU (high- grade tumors) or conservative management and follow-up (low-grade tumor).

RESULTS

RNU was performed in 31 patients, while the remaining 47 patients (undergone Tm:YAG ablation only) were followed up for a mean of 11.7 months with only 19.2% of patients showing upper tract recurrence and no patients showed postoperative ureteral strictures. Limitations include the short follow-up and retrospective nature of the study.

CONCLUSIONS

On the short term, thulium Laser ablation of UTUC is safe and feasible especially in low-grade UTUC.

Consultation on UTUC, Stockholm 2018 aspects of diagnosis of upper tract urothelial carcinoma

Purpose

To summarize knowledge on upper urinary tract carcinoma (UTUC) regarding diagnostic procedures, risk factors and prognostic markers.

Methods

A scoping review approach was applied to search literature in Pubmed, Web of Science, and Embase. Consensus was reached through discussions at Consultation on UTUC in Stockholm, September 2018.

Results

Tumor stage and grade are the most important prognostic factors. CT urography (CTU) including corticomedullary phase is the preferred imaging modality. A clear tumor on CTU in combination with high-grade UTUC in urine cytology identifies high-risk UTUC, and in some cases indirect staging can be obtained. Bladder urine cytology has limited sensitivity, and in most cases ureterorenoscopy (URS) with in situ samples for cytology and histopathology are mandatory for exact diagnosis. Image-enhancing techniques, Image S1 and narrow-band imaging, may improve tumor detection at URS. Direct confocal laser endomicroscopy may help to define grade during URS. There is strong correlation between stage and grade, accordingly correct grading is crucial. The correlation is more pronounced using the 1999 WHO than the 2004 classification: however, the 1999 system risks greater interobserver variability. Using both systems is advisable. A number of tissue-based molecular markers have been studied. None has proven ready for use in clinical practice.

Conclusions

Correct grading and staging of UTUC are mandatory for adequate treatment decisions. Optimal diagnostic workup should include CTU with corticomedullary phase, URS with in situ cytology and biopsies. Both WHO classification systems (1999 and 2004) should be used to decrease risk of undergrading or overtreatment.

[Biopsy techniques in the upper urinary tract for the diagnosis of urothelial carcinoma: systematic review]

BACKGROUND

The diagnostic accuracy of ureteroscopic biopsies in the upper urinary tract is limited by technical difficulties during extraction and small sample size.

OBJECTIVES

To evaluate the impact of different techniques and instruments on the histopathologic quality and diagnostic yield of extracted samples as well as the predictive value of clinical grading and staging on final pathologic stage at radical nephroureterectomy.

MATERIALS AND METHODS

For this systematic review, we searched PubMed and Embase databases for original publications and meeting abstracts according to the PRISMA guidelines.

RESULTS

Overall, we included 23 studies which comprised a total of 1547 biopsies for the investigation of diagnostic yield and 778 patients for the assessment of grade and stage concordance. We found that the median diagnostic yields of big retrograde 2F [french] forceps, antegrade 3F forceps and baskets in combination with forceps were 92% (range 83-100), 72% (50-90) and 91% (78-94), respectively. Median rates of grade concordance and upgrading across all techniques ranged between 78-89% and 5-16%, respectively, without relevant differences.

CONCLUSIONS

The choice of biopsy technique affects the ability to diagnose upper tract urothelial carcinoma. The correct determination of pathologic grading is comparable between different techniques. The combination of biopsy forceps and baskets during ureterorenoscopy seems to achieve optimal diagnostic accuracy.

Cryobiopsy in the Upper Urinary Tract: Preclinical Evaluation of a Novel Device

OBJECTIVE

To develop a novel device for cryobiopsy of the upper urinary tract (UUT) and to evaluate its feasibility in a standardized preclinical setting.

MATERIALS AND METHODS

Flexible cryoprobes (diameter 0.9 mm; cooling agent CO2) were developed and used to extract biopsies in porcine UUTs. Cryosamples obtained by ureterorenoscopy were systematically compared with biopsy specimens obtained with standard of care devices in terms of physical characteristics (deflection angle and irrigation flow rates) and histologic criteria (assessability).

RESULTS

Irrigation flow rates were significantly higher with introduced BIGopsy (2.8 ± 0.1) compared with standard forceps (0.94 ± 0.06; P < .001) and cryoprobe (1.1 ± 0.1; P < .001). Angular deflection was significantly reduced by the inserted cryoprobe (130.7° ± 1.2° vs 166.9° ± 1.1° [BIGopsy] or 161.4° ± 1.9° [standard forceps]; both P < .001). Significantly larger UUT tissue samples were obtained by the cryoprobe (mean specimen area 7.5 ± 2.5 vs 4.6 ± 2.5 mm² [BIGopsy] or 1.4 ± 1.4 mm² [standard forceps]; both P < .001). No crush artifacts were observed in cryosamples. Superior histologic assessability scores were achieved in samples obtained by the cryoprobe (mean 2.8 ± 0.8) and BIGopsy (2.3 ± 1.9) when compared with standard forceps (0.4 ± 0.9; P < .001).

CONCLUSION

Cryobiopsy in the UUT is feasible and represents a viable new option to improve the diagnostic accuracy of histopathologic evaluation. Larger and more representative tissue samples can be obtained using a cryoprobe and artifacts may be avoided. Further optimization of the probe will reduce possible restrictions of ureterorenoscopy handling when the device is inserted.

Endoscopic Treatment of Upper Tract Urothelial Carcinoma

PURPOSE OF REVIEW

This study aims to make the reader be aware of recent trends regarding the endoscopic management of upper tract urothelial carcinoma (UTUC) via review of the urologic literature over the past 5 years. Given the rare incidence of this disease, and the lack of level 1 evidence, systematic reviews and meta-analyses were also evaluated. Studies of importance are also considered and outlined in the annotated reference section.

RECENT FINDINGS

The PubMed database was queried using the following medical subject headings (MeSH terms): "carcinoma, transitional cell," "ureter," "ureteral neoplasms," "kidney pelvis," "endoscopy," "laser therapy," "ureteroscopy," "urologic surgical procedures," and "ureteroscopes." MeSH terms were linked together in varying combinations and limited to human studies in English. Given the relatively rare nature of upper tract urothelial carcinoma (UTUC), level 1 evidence regarding the efficacy of endoscopic treatment does not exist, even after 30+ years of experience. Rather, the literature available mostly is in the form of single institutional retrospective series consisting of relatively small numbers of patients with short to intermediate follow-up. Only within the last 3 years have published series with larger numbers of patients and mean follow-up over 5 years been made available. Even with these more robust experiences, comparisons among series are difficult given variable treatment and follow-up approaches. Most endoscopically managed UTUC will locally recur, especially with longer follow-up. Renal preservation rate is high, however, approaching 80% with follow-up well over 3 years. Patients with high-grade disease often fare poorly regardless of treatment modality. As such, endoscopic management for high-grade urothelial carcinoma should only be used in exceptional circumstances (i.e., in those patients medically unfit for NU or those with solitary kidneys wishing to avoid the morbidity of dialysis). No level 1 evidence exists for the routine use of intraluminal adjuvant therapy for UTUC (i.e., BCG and Mitomycin C) and multiple retrospective observational series claim there is no overt benefit. The recent formation of multiple international groups with interest in UTUC may eventually lead to the production of level 1 studies regarding optimal treatment; however, uniformity in treatment approach will likely still offer challenges.

A Novel Technique to Improve the Processing of Minute Ureteroscopic Biopsies

To examine the ability of a new specimen handling technique to improve histopathological yield of ureteroscopic biopsies, performed in patients with suspected upper tract urothelial carcinoma (UTUC). In a bi-center retrospective study we compared the results of the new tissue handling technique (group 1) with the standard technique (group 2). In the new technique, to achieve maximal tissue preservation, the specimen is mounted on filter paper prior to embedding in paraffin. Multivariate analysis was performed to determine which factors are associated with optimal histological results. We further compared the biopsies with the final specimen in a subgroup of patients who underwent nephroureterectomy (NU). Of 55 ureteroscopic biopsies, 1 biopsy from group 1 (new technique) and 3 biopsies from group 2 (standard technique) were inadequate for pathological examination. 51 UTUC specimens were analyzed. Tumor grade and stage were determined in 85% and 63% of the patients in group 1 and in 83% and 25% of group 2 (p=0.85 and p=0.007). Orientation was preserved in 82% of group 1 and 42% of group 2 (p=0.003). On multivariate analysis biopsy technique and biopsy diameter were found to predict stage determination (p=0.01 and p=0.007) and tissue orientation (p=0.005 and p=0.04). Among patients who underwent NU, stage concordance between the biopsy and final pathology was observed in 56% and 27% of the patients in group 1 and 2, respectively. The new processing technique for small UTUC forceps biopsies decreases the rate of biopsies with insufficient material and improves biopsy interpretation.

Minimally Invasive Therapy for Upper Tract Urothelial Cell Cancer

Minimally invasive therapy for upper tract urothelial cell cancer has assumed an important role in the management of this relatively uncommon genitourinary malignancy. In this review, current standards for patient selection, surgical approach, as well as overall outcomes will be discussed. Moreover, the use of intraluminal agents in upper tract disease is examined along with its efficacy and associated complications.

Use of ureteral access sheaths in ureteroscopy

The ureteral access sheath (UAS) facilitates the use of flexible ureteroscopy, enabling improved minimally invasive management of complex upper urinary tract diseases. The UAS, which comes in a variety of diameters and lengths, is passed in a retrograde fashion, aided by a hydrophilic coating and other features designed to confer smooth passage into the ureter with sufficient resistance to kinking and buckling. Use of a UAS has the advantage of enabling repeated passage of the ureteroscope while minimizing damage to the ureter, thus improving the flow of irrigation fluid and visualization within the urethra with reductions in operative times, which improves both the effectiveness of the surgery and reduces the costs. Placement of the UAS carries an increased risk of ureteral wall ischaemia and injury to the mucosal or muscular layers of the ureter, and a theoretically increased risk of ureteral strictures. A ureteral stent is typically placed after ureteroscopy with a UAS. Endourologists have found several additional practical uses of a UAS, such as the percutaneous treatment of patients with ureteral stones, and solutions to other endourological challenges.

Carcinoma in situ is significantly underdetected by prenephroureterectomy ureteroscopy in the management of upper tract urothelial cancers

Objective. Diagnostic reliability of prenephroureterectomy ureteroscopy (PNU) for the detection of upper tract carcinoma in situ (CIS) remains unproven in particular and underreported in general. Methods. Patients who underwent radical nephroureterectomy (RNU) in a large multicentre retrospective study for upper tract transitional cell carcinoma (UT-TCC) between January 2002 and December 2013 were identified from our hospitals databases. PNU appearances, stage, and grade of ureteroscopic biopsy were compared with final histology results of RNU to assess the diagnostic reliability of PNU for carcinoma in situ (CIS). Results. Three hundred patients underwent RNU for UT-TCC. 106 (106/300; 35.3%) of the cohort had PNU using white light with biopsies taken in most (92/106; 86.7%). Postnephroureterectomy histology of the cohort showed CIS in 65 (65/300; 21.6%) patients. Thirty nine of patients with CIS (39/65; 60%) had prenephroureterectomy ureteroscopy biopsies. Out of ten patients with CIS on ureteroscopic biopsies, six did not show CIS on final histopathology (6/10; 60%). Moreover, grading and staging on PNU biopsies of obvious tumours showed a significant nonconcordance with final histopathology of RNU specimen (P = 0.02). Overall survival was also shorter in patients with CIS compared with those without; this showed strong statistical significance (P = 0.004). Conclusions. There is a high incidence of CIS in upper tract with significant underdetection and discordance rate between the histopathology of biopsy samples obtained by white light PNU and resected specimen of radical nephroureterectomy. The presence of concomitant CIS and high stage disease in the upper tract TCC carried a poor prognosis following radical nephroureterectomy.

Highlights from the first symposium on upper tract urothelial carcinoma

OBJECTIVES

Upper tract urothelial carcinoma (UTUC) is a rare disease in Western countries and garners little focused attention in urologic and oncologic circles. We report highlights from the first symposium on UTUC.

METHODS

All participants were asked to provide a summary of their presentation to be included as part of these proceedings. Submitted summaries were synthesized into this document. All contributors reviewed and provided input on the final draft.

RESULTS

Five highlights are included in this report, including landmark research that not only reveals the likely cause of Balkan endemic nephropathy and associated UTUC but also links it directly to UTUC in Taiwan. Because of the ubiquitous use of Aristolochia plants in these herbal remedies, a public health problem of considerable magnitude is anticipated in Asian countries. Gene expression signatures reveal some differential expression in bladder carcinoma, such as CLCA2 and GABRE. Few urinary markers have proven utility for the diagnosis and follow-up of UTUC, and no tissue or blood-based markers are currently undergoing clinical application. Novel endoscopic therapies provide some hope of improving tissue sampling, diagnosis, and kidney-sparing therapeutics, but the greatest potential lies in improving clinical (preoperative) risk stratification, which is critically limited in this disease. Biomarkers, currently untested, hold promise in identifying patients most likely to benefit from perioperative chemotherapy and at high risk from cisplatin-induced nephrotoxicity.

CONCLUSIONS

Despite its rarity in the West, UTUC is reaching potentially epidemic proportions in the East because of exposure to carcinogenic herbal remedies. Critical trials are needed to improve our understanding and treatment of UTUC. Because of the broad range of comorbid conditions in patients suffering from this disease, it is the consensus of the participants that future clinical trials should be practical in design and applicable to a broad range of patients, diverging from the current dogma of narrow patient selection criteria in clinical trials. Practical designs would maximize accrual for a still uncommon disease, and their findings would be applicable to a larger proportion of patients than current narrowly selected designs.

Which ureteral access sheath is compatible with your flexible ureteroscope?

PURPOSE

Our aim is to evaluate different ureteral access sheaths (UASs), which are available in the international market and their compatibility with different available flexible ureteroscopes (F-URSs) to help the urologist choose the proper ureteral access sheath for his or her endoscope before commencing the procedure.

MATERIALS AND METHODS

A total of 21 UASs and 12 F-URSs were evaluated. Measurements were obtained in French (F) units considering different characteristics for each UAS and each F-URS. Insertion test without friction between F-URS and UAS was considered as a successful test and was referred as (YES).

RESULTS

All UASs and F-URSs were successfully submitted to the insertion test. All F-URSs that were inserted into UASs without friction had an internal diameter of at least 12F. Different lengths of UAS did not influence the test outcome.

CONCLUSION

This study was able to establish a correlation table between different UASs and different flexible ureteroscopes. As of now, the 12/14F UAS is considered the universal UAS that accepts all F-URSs that are available in the endourology field. Nevertheless, we are expecting a significant change with the new standard size 10/12F UAS as well as huge advances in minimizing the size of different endoscopes.

Standardized ex vivo comparison of different upper urinary tract biopsy devices: impact on ureterorenoscopes and tissue quality

OBJECTIVES

To evaluate the influence of different biopsy forcipes on the deflection, irrigant flow, and optical characteristics of flexible ureterorenoscopes and to assess tissue quality for histopathologic evaluation in an ex vivo setting.

MATERIALS AND METHODS

The following five different biopsy forcipes were compared: Olympus (FB-56D-1; diameter 5Fr.), R. Wolf (829.601; 3Fr.), Karl Storz Medical (11275ZE; 3Fr.), Boston Scientific (Piranha; 505-160; 3 Fr.), and Cook BIGopsy (115CM; 2.4 Fr.). The devices were tested in 3 different ureterorenoscopes: Storz 11278 VU (Flex-X(2)), Storz 11278 V (Flex-X(C)), and Wolf Cobra (7326071/-6). Tissue samples were obtained from porcine upper urinary tracts.

RESULTS

Baseline irrigation flow rates with empty channels were significantly higher in the Wolf Cobra than in Storz ureterorenoscopes (30.5 vs. 23 and 21 ml/min). The BIGopsy forceps allowed for higher flow rates in both Storz ureterorenoscopes (2.2 and 1.3, respectively) when compared to the other devices (0.5 and 0.6 ml/min). The Storz and Wolf biopsy forcipes resulted in the highest impairment of the deflection angle. In all 3 ureterorenoscopes, flow rates and deflection angle were least impaired by the BIGopsy. However, BIGopsy compromised the field of view (20 % reduction vs. 12 % by others). The largest sample of renal pelvis and ureter biopsies was obtained with BIGopsy and Storz(®) forcipes, respectively. The extent of artifacts and denuded urothelium were comparable in all samples.

CONCLUSIONS

The various biopsy devices showed different impacts on irrigation flow, deflection, and field of view. The Cook BIGopsy best retains irrigation flow in single-channel flexible ureterorenoscopes and deflection. However, a smaller field of view may complicate handling and tissue acquisition.

Ureterorenoscopic biopsy and urinary cytology according to the 2004 WHO classification underestimate tumor grading in upper urinary tract urothelial carcinoma

OBJECTIVES

To determine accuracy of upper tract cytology and ureteroscopic biopsy according to the 2004 World Health Organization (WHO) classification in predicting the correct tumor grade in patients with urothelial cancer of the upper urinary tract (UUT-UC).

METHODS

Pathology reports of 77 nephroureterectomy specimens were retrospectively analyzed for tumor grade and compared with preoperatively gained cytology and ureteroscopic biopsy results. For analysis, the 2004 WHO classification was used.

RESULTS

Overall sensitivity of cytology and biopsy in diagnosis of UUT-UC was 64% and 74%, respectively. Accuracy of cytology and biopsy in predicting high grade cancer was 53% and 58%, respectively. Combination of cytology and biopsy could improve sensitivity (84%) and accuracy (68%), but even for this combination, 15% of high grade tumors were misinterpreted as low grade cancer.

CONCLUSION

Our results show only limited accuracy for preoperative cytology and ureterorenoscopically performed biopsies in the prediction of the correct tumor grading of an UUT-UC. Therefore, we suggest the use of additional diagnostic procedures before the decision for definitive surgical treatment in patients with UUT-UC is made.