Abstract
Background: Urine cytology is a highly effective, straightforward, and cost-efficient diagnostic tool for identifying neoplastic and non-neoplastic changes in the bladder, ureter, and renal pelvis. The aim of this study is to demonstrate the high sensitivity and specificity of urine cytology in detecting a wide range of urothelial lesions, including metastatic involvement. Material and Methods: Urine cytology was performed on 9639 cases between 2000 and 2025. The samples, collected from patients, were processed at the Institute of Pathology. Cytological slides were prepared using cytocentrifugation and stained with May–Grünwald–Giemsa (MGG) and Papanicolaou stains. The cytological findings were classified according to WHO, 2004 compared with histological specimens. Additionally, selected cases underwent immunohistochemical and molecular analyses. All samples were anonymized and retrospectively analyzed following the guidelines and regulations of the local ethics committee. Results: Of the total cases, 7051 were classified as benign, 1269 as malignant, and 88 as normal findings. Insufficient material was obtained in 336 cases. No complications were reported during sample collection or processing. The concordance with histological findings for neoplastic lesions was over 96%, with a false-negative rate of 1.84%. The diagnostic methods demonstrated a sensitivity of 90.7% and a specificity of 96.64%. Among the 6956 cases analyzed, 3139 were women (45.13%) and 3817 were men (54.87%). Conclusions: The diagnostic value of urine cytology in representative material is relatively high in assessing both the presence or absence of malignancy and, when applicable, the tumor grade. This large 25-year single-center review demonstrates that urine cytology retains high sensitivity and specificity for the detection of urothelial malignancy, particularly high-grade disease. However, the atypical category remains a major diagnostic challenge and contributes substantially to false-positive results.