Aims: The current study assessed the prognosis of papillary urothelial hyperplasia as its significance is uncertain due to limited studies on this topic.
Methods: 53 patients with papillary urothelial hyperplasia were identified from the files of the senior author.
Results: There were 40 males and 13 females with ages ranging from 46 to 101 years (median 74 years). The two most common reasons for performance of cystoscopy with biopsy was follow-up for a papillary urothelial neoplasm (24 cases) and haematuria (19 cases). The most common cystoscopic findings were papillary tumour (24 cases), papillary irregularity (10 cases), and irregular mucosa (9 cases). Prior to the diagnosis of papillary urothelial hyperplasia, 30 patients had a history of 43 prior neoplasms, 79% of which were low grade papillary urothelial neoplasms. After allowing for a minimum of 6 months of follow-up, 15 patients had 20 subsequent neoplasms, 67% which were low grade. Eleven of 30 (37%) patients with prior urothelial neoplasia subsequently developed bladder tumours compared to four of 23 (17%) patients without a prior history of bladder neoplasia. The 5 year actuarial risk of subsequently developing urothelial neoplasia following the diagnosis of papillary urothelial hyperplasia was 27.4% and 47.8% for patients without and with a prior history of papillary neoplasia, respectively (p = 0.18), with a combined risk of 38.6%. All together 35 of 53 (66%) had a history of prior, concurrent, or subsequent urothelial neoplasia.
Conclusions: Papillary urothelial hyperplasia appears to be a precursor lesion to papillary urothelial neoplasms, predominantly lower grade lesions, and follow-up is warranted.