Unusual bladder masses in children.

Benign and malignant bladder masses in children are extremely rare pathologic lesions. The presentation can include gross hematuria, irritable or obstructive voiding symptoms, and urinary infection. We present 2 cases in which large bladder masses suspicious for malignancy were diagnosed as benign lesions. One patient presented with abdominal pain and frequency 2 weeks after a minor bicycle accident and had a bladder wall abscess with sterile urine. Another child presented with gross hematuria and was found to have a giant cystitis glandularis lesion with no precipitating event or infection. The evaluation and differential diagnosis are discussed, and a review of the literature is presented.