Malignancy yield and clinical predictors in radiologically detected adult urachal anomalies: A retrospective cohort study

Abstract Objective To evaluate the occurrence of bladder malignancy or papillary urothelial neoplasm of low malignant potential (PUNLMP) detected at initial evaluation or during follow‐up among adults with radiologically reported urachal anomalies, and to explore clinical factors associated with neoplasia. Materials and methods We conducted a retrospective single‐centre cohort study. Adult patients with radiologically reported urachal anomalies between 2000 and 2024 were identified through institutional radiology information system and report archive and underwent detailed chart review. Patients with a prior history of bladder or upper urinary tract malignancy were excluded. Clinical presentation, imaging findings, cystoscopy, histopathology and outcomes were analysed. Clinical variables associated with malignancy were explored using Firth penalized logistic regression. Results A total of 245 patients were included: 92/245 (38%) had incidental/asymptomatic findings and 153/245 (62%) were symptomatic. Bladder malignancy/PUNLMP was detected in 14/245 patients (5.7%) overall, including 0/92 incidental/asymptomatic patients (0%) and 14/153 symptomatic patients (9.2%). Macroscopic haematuria was present in 12/14 patients with malignancy/PUNLMP and was associated with a higher frequency of neoplasia: 12/66 patients with haematuria (18%) versus 2/179 without haematuria (1%; p<0.001). In exploratory multivariable analysis, macroscopic haematuria remained associated with malignancy/PUNLMP (OR 5.29, 95% CI 1.10–39.5). Most detected tumours were of non‐urachal histology, and 8/14 (57%) were stage T2 or higher. Conclusions Incidentally detected urachal anomalies in adults were not associated with malignancy during follow‐up, suggesting that conservative management may be appropriate in asymptomatic patients. In contrast, symptomatic presentation, particularly macroscopic haematuria, warrants thorough urological evaluation due to its association with a substantially increased risk of bladder malignancy.