Utility and Diagnostic Accuracy of Ureteroscopic Biopsy in Upper Tract Urothelial Carcinoma

Abstract

Context.-Ureteroscopic biopsy is the gold standard for the histopathologic diagnosis of urothelial carcinoma of the upper urinary tract.Objective.-To assess the accuracy of endoscopically obtained biopsy samples in diagnosing, grading, and staging urothelial carcinoma and correlate diagnostic findings to biopsy sample size.Design.-We retrospectively reviewed endoscopic biopsies of the ureter, renal pelvis, and ureteropelvic junction from 2008 to 2011. Biopsy diagnoses that were discordant with follow-up pathology and/or ureteroscopic impression were rereviewed and samples were immunohistochemically analyzed.Results.-Endoscopic biopsies (n ¼ 118) yielded a sensitivity of 85.4% for the ureter (n ¼ 79), 77.8% for the renal pelvis (n ¼ 37), and 100% for the ureteropelvic junction (n ¼ 2). A specificity of 100% for all locations and a diagnostic accuracy of 98.3% were identified. The median sample size was 0.3 cm for true positives, 0.3 cm for true negatives, and 0.2 cm for false negatives with no statistical significance. We found that 87.1% of tumors diagnosed on biopsy had concordant grade and 60.0% had concordant pT stage with follow-up surgical resections (n ¼ 43) and biopsies (n ¼ 24). Biopsy samples with concordant tumor grades (mean ¼ 0.6 cm) compared with follow-up resection were larger than biopsy samples with discordant grades (mean ¼ 0.3 cm) (P ¼ .04).Conclusions.-Though highly specific, endoscopic biopsy does provide a significant false-negative rate owing to both sampling and diagnostic errors when assessing the upper urinary tract for urothelial carcinoma. Tumor grading is accurate, particularly with larger tissue samples, but tumor staging is unreliable.

Percutaneous Image-guided Core Needle Biopsy for Upper Tract Urothelial Carcinoma

“…This is higher than approximately 83%-94% histologic diagnosis yield in endoscopic biopsy series for UTUC. [5][6][7] Notably, elevated BMI was also not associated with decreased success or diagnostic yield in our series. Both CT and US guided techniques had equal success with obtaining tissue for diagnosis, although this was after a radiologist chose the preferred guidance modality based on lesion characteristics and therefore might not be fully generalizable.…”

“…Ureteroscopic biopsy, the usual approach to obtain tissue in suspected UTUC, has many limitations and a 83%-94% sensitivity for the histologic diagnosis of UTUC. [5][6][7] On the other hand, grade concordance of ureteroscopic biopsy with RNU is generally lower, estimated around 70%. [5][6][7][8][9][10] This stems from limitations in the size of tissue fragments able to be ureteroscopically extracted.…”

Ureteroscopic Biopsy of Upper Tract Urothelial Carcinoma: Comparison of Basket and Forceps

“…Other series have shown that larger biopsy specimens tend to correlate well with the grade of the final specimen. 17 Although not specifically evaluated in this study, in our experience, we have found that the basket does not limit the deflection of the flexible ureteroscope as much as the forceps (Fig. 3).…”

Pathology of Upper Tract Urothelial Carcinoma with Emphasis on Staging

“…Muscularis propria is rarely present in upper tract biopsies, and some biopsies may be so superficialthat only epithelium is present, precluding assessment of invasion. In the study by Vashistha et al, they reported a pT stage concordance of 60% for biopsies in which a stage was designated (20). The ureter (59.3%) and renal pelvis (62.5%) had similar pT stage concordance for biopsies.…”