Risk of malignancy assessment for the Paris System for reporting urinary cytology

Abstract

Background: The Paris System for reporting urinary cytology was introduced in 2013 and has a global impact. In our study, we assess the risk of malignancy (ROM) for each diagnostic category and our diagnostic accuracy in urinary cytology. Methods: We have conducted a prospective study during 2019, including only new cases of urothelial neoplasms, all of them with subsequent histology. The risk of malignancy for each category was calculated and the diagnostic accuracy parameters were estimated in correlation with histology. Results: The estimated risk of malignancy (ROM) for high-grade neoplasms was 0% for TPS1, 6.5% (2/31) for TPS2, 36% (9/25) for TPS3, 65% (13/20) for TPS4, 100% (18/18) for TPS5 and 16% (2/13) for TPS6. Accuracy parameters for high-grade urothelial carcinoma (HGUC) were evaluated in two ways, in the first considering TPS3 as a negative and in the second as a positive result and the values were: sensitivity 70% vs 90.9%, specificity 89.3% vs 65.2%, PPV 81.5% vs 63.5%, NPV 82% vs 91.5% and diagnostic accuracy 81.8% vs 75.4%. For low-grade urothelial neoplasm (LGUN) diagnosis, sensitivity was 42%, specificity 76%, PPV 71%, NPV 48.6% and diagnostic accuracy 56%. Conclusion: The risk of malignancy for the TPS categories has a clinically meaningful gradation and the effectiveness of urinary cytology is improved by the application of the Paris System.

The Paris system classification for urinary cytology in patients under bacillus Calmette‐Guerin treatment

“…The overall accuracy parameters prove that cytology is an efficient diagnostic tool for the group of BCG patients. Comparison of accuracy between the group of BCG patients and our previously published data of the group of patients without history of urothelial malignancy, 9 shown in Table 6, shows that cytology using the TPS classification is even more efficient in the group of BCG patients (91.7% vs. 81.8% or 93% vs. 75.4%), although sensitivity is substantially lower. This finding contradicts with the well-established perception of hampered cytology efficacy in the BCG-treated patients' group, [14][15][16][17][18][19][20][21][22] but it is in accordance with the recent study of Gupta et al 28 We consider that the most important issue is the presence of clinical information on any kind of previous history and/or treatment.…”

“…In 2013, at the International Congress of Cytology, the Paris system working group was organized by joint efforts of the International Academy of Cytology and the American Society of Cytopathology and in 2016 the Paris System for Reporting Urinary Cytology (TPS) was published 5,6 . This reporting system, validated in several studies, 7–10 presented strictly defined morphologic criteria for each diagnostic category and divided the reports into the following categories: inadequate urinary specimen (Inadequate‐TPS1), negative for high‐grade urothelial carcinoma (NHGUC‐TPS2), atypical urothelial cells (AUC‐TPS3), suspicious for high‐grade urothelial carcinoma (SHGUC‐TPS4), high‐grade urothelial carcinoma (HGUC‐TPS5), low‐grade urothelial neoplasia (LGUN‐TPS6) and other malignancies (TPS7).…”

“…Comparison of accuracy parameters between the group of BCG patients and the group of patients without clinical history9 Comparison of ROHM between the group of BCG patients and the group of patients without clinical history9 …”

Impact of bacillus Calmette‐Guerin intravesical therapy on the diagnostic efficacy of The Paris System for Reporting Urinary Cytology in patients with high‐grade bladder cancer

“…A cytologic study that included 110 cases with histopathologic correlation reported a sensitivity of 90.9% when atypical cytology cases were included compared with 70% when SHGUC and HGUC cases were included. 25 Sensitivity for HGUC in cohorts that did not receive BCG therapy ranges between 70.5% and 84%. 10,12 Therefore, it seems to be of utmost importance to consider differences in cutoff definitions, classification systems applied, and cohort characteristics when comparing the efficacy of urinary cytology between different studies.…”

“…Also, in cohorts that did not receive BCG therapy, urinary cytology seemed to be highly dependent on the cutoff used. A cytologic study that included 110 cases with histopathologic correlation reported a sensitivity of 90.9% when atypical cytology cases were included compared with 70% when SHGUC and HGUC cases were included 25 . Sensitivity for HGUC in cohorts that did not receive BCG therapy ranges between 70.5% and 84% 10,12 .…”