Outcome analysis and negative predictive value of the "unsatisfactory/nondiagnostic" category of The Paris System for Reporting Urinary Cytology.

The Paris System (TPS) for Reporting Urinary Cytology (UCyto) was published in 2016, but to date, no study addressing the unsatisfactory (UNSAT) category has been published. We aimed to identify the negative predictive value (NPV) for UNSAT UCyto after the implementation of TPS at our institution. For the period from January 1, 2017, to December 31, 2019, we identified all cases with UNSAT diagnosis on UCyto specimens and available cytologic and/or surgical pathology follow-up within 6 months from the UNSAT diagnosis. Cases were deemed true negative (TN) if the follow-up was "negative for high-grade urothelial carcinoma" (NHGUC). Information regarding previous medical history, clinical indications, and specimen type were tabulated and analyzed. From 6348 UCyto specimens, there were 230 (3.6%) UNSAT diagnoses made on 209 patients (112 [53.6%] men and 97 [46.4%] women) with a median age of 64 years. Of these, 116 UCyto specimens from 106 patients, which had cytologic and/or surgical pathology follow-up within 6 months, were further studied. Most UNSAT UCyto specimens were bladder washing/barbotage (BW/BB), and the most common indication for UCyto was cancer surveillance. The main cause of UNSAT UCyto was low cellularity. There were 5 false-negative (FN) results for high-grade urothelial carcinoma (HGUC), which corresponds to an overall NPV of 84.4%. NPV was highest for patients with UCyto for hematuria, and for patients with BW/BB as UCyto specimen type. Our results show that UNSAT diagnoses have a lower NPV than that typical of NHGUC diagnoses, and should be managed accordingly. • In 2016, The Paris System (TPS) for Reporting Urinary Cytology (UCyto) was published and still there have not been any publications focusing on the outcome, risk of malignancy, or negative predictive value (NPV) of the unsatisfactory (UNSAT) category. We aimed to identtify the outcome and the NPV for UNSAT after the implementation of TPS at our institution. • The cases were deemed true negative (TN) if the 6 month follow up was negative. The urine specimen was considered "UNSAT" when it did not meet the adequacy criteria per TPS. • There were 230 (3.6%) UNSAT specimens from a total of 6348 UCyto specimens. Of these, 116 UCyto specimens from 106 patients, which had cytologic and/or surgical pathology follow-up within 6-months, were further studied. Only 50.7 % (106 of 209) of the patients had a follow-up. • An overall NPV of 84.4% was calculated for UNSAT UCyto. When this was compared with previous published worked for "negative" UCyto, it showed that the UNSAT UCyto according to TPS were lower for all indications and specimen types. • UNSAT UCyto is not equivalent to other UCyto categories and does not represent a "true negative" result. All other parameters, like history, clinical presentation, cystoscopy findings, and any prior UCyto or biopsy result, should be considered and patients managed accordingly. [ABSTRACT FROM AUTHOR]