Background: Urothelial carcinoma (UC) is the most common malignancy of the urinary tract, accounting for nearly 90% of bladder cancers. Early diagnosis is crucial for reducing morbidity, preventing disease progression, and improving survival. Urinary cytology remains a valuable non-invasive diagnostic tool for detecting urothelial carcinoma, particularly high-grade lesions and carcinoma in situ. Despite advances in urinary biomarkers and molecular diagnostic techniques, conventional urinary cytology continues to play a significant role in routine clinical practice due to its simplicity, cost-effectiveness, and high specificity.

Objective: To evaluate the diagnostic utility of urinary cytology in detecting urothelial carcinoma and identify cytomorphological features associated with malignant urothelial cells.

Materials and Methods: A retrospective observational study was conducted on 220 urine specimens collected over five years from patients clinically suspected of having urothelial carcinoma. Conventional cytological smears were examined using Papanicolaou and May-Grünwald-Giemsa stains. Cytological findings were classified according to The Paris System for Reporting Urinary Cytology (TPS). Histopathological diagnosis from cystoscopic biopsy served as the gold standard. Diagnostic indices including sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall accuracy were calculated.

Results: Among 220 cases, histopathology confirmed urothelial carcinoma in 86 patients (39.1%). Urinary cytology correctly identified 74 malignant cases and 126 benign cases. Overall sensitivity was 86.0%, specificity 94.0%, PPV 90.2%, NPV 91.9%, and diagnostic accuracy 90.9%. High-grade urothelial carcinoma demonstrated significantly greater detection rates compared with low-grade lesions. Cytological predictors of malignancy included increased nuclear-to-cytoplasmic ratio, hyperchromasia, irregular nuclear membranes, coarse chromatin, prominent nucleoli, and cellular discohesion.

Conclusion: Urinary cytology remains a highly specific diagnostic modality for detecting high-grade urothelial carcinoma and serves as an important adjunct to cystoscopy. Standardized reporting using The Paris System enhances diagnostic reproducibility and clinical decision-making.