Cytological examination of voided urine (VU) or washings (barbotages) obtained from the upper urinary tract (UUT) is often a component of the diagnostic workup for UTUC. Tissue biopsies of UUT lesions can be challenging due to the increased difficulty of visualization and access of these lesions during ureteroscopy.
Sep 8, 2020In comparison with ureteroscopic biopsies, UUT cytology has shown comparable diagnostic performance, but improvements in detection rates of UTUC Pre-TPS Evaluation of UUT Diagnostic Rates of TPS Low-Grade Urothelial
Cytological examination of voided urine (VU) or washings (barbotages) obtained from the upper urinary tract (UUT) is often a component of the diagnostic workup for UTUC. Tissue biopsies of UUT lesions can be challenging due to the increased difficulty of visualization and access of these lesions during ureteroscopy.
Explanatory Note 1
In a barbotage/washing specimen that adequately samples a suspicious lesion, many abnormal cells should be seen in the specimen if the neoplasm is HGUC.
In instances where a distinct lesion cannot be seen on uroscopy and selective cytology is being used to localize HGUC identified on a prior voided urine specimen, a flat CIS or small papillary HGUC.
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Explanatory Note 2
When diagnosing HGUC in upper tract specimens, circumspection is recommended, favoring specificity over sensitivity.
In other words, the diagnosis of HGUC in upper tract specimens should be reserved for those cases with indisputable qualitative criteria (Fig. 7.6 a).
Due to the infrequency of diagnosing UTHGUC, review by a second pathologist is pru.
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General Criteria For HGUC
TPS cytomorphological criteria for HGUC is the same for upper and lower tract specimens (Figs. 7.1, 7.2, 7.3, 7.4, and 7.5), and a detailed discussion can be found in Chap. 6 [15,16,17,18,19].
A recent study using digital image analysis determined that UTHGUCs have higher N/C ratios, smaller cell circumference, smaller nuclei, and less cytoplasm co.
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Upper Tract HGUC in Instrumented Specimens
Only a few pre-TPS studies have assessed specific cytomorphologic features predictive of UTUC in UUT specimens [21].
Potts et al. [22] found that increased nuclear-to-cytoplasmic (N/C) ratio, anisonucleosis, and overlapping nuclei were distinguishing features for identifying UTHGUC.
Witte et al. [23] reviewed a cohort of renal pelvis washing specim.
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Upper Tract HGUC in Voided Urine Specimens
The criteria for diagnosing UTHGUC cells in VU specimens are the same criteria used to diagnose HGUC of the lower urinary tract, as the location of HGUC cannot be determined in VU specimens.
UTHGUC cells are more likely to be degenerated in VU due to increased transit times and thus are more likely to be diagnosed as atypical urothelial cells (AUC).
