UROTHELIAL NEOPLASMS IN PATIENTS 20 YEARS OR YOUNGER: A CLINICOPATHOLOGICAL ANALYSIS USING THE WORLD HEALTH ORGANIZATION 2004 BLADDER CONSENSUS CLASSIFICATION

Abstract

Urothelial neoplasms in patients younger than 20 years are rare, with conflicting data regarding clinical outcomes. We identified 23 patients 4 to 20 years old with urothelial neoplasms, reclassified the microscopic diagnoses using the 2004 WHO/International Society of Urologic Pathology grading classification and collected data on presentation, risk factors and outcomes. Pathological grading revealed 2 urothelial papillomas, 10 papillary urothelial neoplasms of low malignant potential (PUNLMPs), and 8 low grade and 3 high grade papillary urothelial cancers, all without invasion. Mean patient age was 13.2 years (range 4 to 20), 19 patients were male and 19 presented with gross hematuria. All lesions were solitary and measured 0.1 to 6 cm. One patient had a history of smoking and 1 had parents who smoked. Three patients (13%) had recurrences classified as either urothelial papilloma (1) or PUNLMP (2). All patients were alive with no evidence of disease after a mean followup of 4.5 years (range 6 months to 13 years). Urothelial neoplasms in individuals younger than 20 years more commonly occur in males and are predominantly low grade with a favorable clinical outcome. Before the current classification system the 10 patients with a diagnosis of PUNLMP would have been classified as having papillary carcinoma. Thus, the diagnostic category of PUNLMP allowed 43.5% of patients in this series to avoid being labeled with "cancer" at a young age.