Tumour Behaviour of Low-Grade Papillary Urothelial Carcinoma: A Single-Centre Retrospective Study

Background and objective Carcinoma of the urinary bladder is the most common urological cancer, and it accounts for 3.9% of all cancer cases in men. Patients with the subset of noninvasive low-grade papillary urothelial carcinoma (LG-UrCa) are at higher risk for tumour recurrence. In this study, we aimed to analyse the histopathological features of LG-UrCa and to correlate those with recurrence potential as well as disease stage and grade progression. Materials and methods We conducted a retrospective study from January 2016 to December 2018. All cases with presenting biopsy initially reported as LG-UrCa were included in the study. All cases with initial biopsy reported as high-grade papillary urothelial carcinoma (HG-UrCa) were excluded from the study. We used the 2016 World Health Organization/International Society of Urological Pathology (WHO/ISUP) guidelines for the classification of papillary urothelial neoplasm. Results A total of 48 initially diagnosed cases of LG-UrCa were identified. Two out of 48 cases were reclassified as high-grade urothelial carcinoma and were excluded from the study. The mean age of patients at presentation was 56.7 years. The mean duration of follow-up was 19.8 months. The mean size of initial tumours was 3.4 cm. Tumour recurrence was encountered in 14 (30.4%) of 46 patients. Out of the four patients who had high-grade progression (8.7%), two also developed TNM stage progression. These two patients eventually underwent radical cystectomy. Patients with larger initial tumour sizes were found to have an increased tumour recurrence rate (p=0.009). Patients with multiple lesions at initial diagnosis had a significantly higher tumour recurrence rate than those with a single tumour (p=0.02). There was no significant difference with regard to intravesical Bacillus Calmette-Guerin (BCG) and tumour recurrence (p=0.065). None of the clinicopathological parameters were significantly associated with the grade and/or stage progression. Conclusion Based on our findings, patients with larger initial tumour size and tumour multiplicity at presentation had an increased tumour recurrence rate.

Automated summary

According to the findings, patients with larger initial tumor sizes and tumor multiplicity at presentation had an increased tumor recurrence rate.