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Updated: Jul 19, 2025

Magnetic Resonance Imaging Assessment of Carcinogen-induced Murine Bladder Tumors
Published on: March 29, 2019
A Prospective Study of the Size, Number and Histopathology of New and Recurrent Bladder Tumors
1Department of Urology, Sahlgrenska University Hospital, Göteborg, Sweden.
Introduction:
We prospectively registered the grade, stage, number and size of bladder tumor recurrences as to our knowledge this has not yet been done. New tumors were included in the study for comparative purposes.
Methods:
All 581 transurethral resections, random biopsies and fulgurations for a suspected bladder tumor were prospectively registered during a 15-month period at a single institution. Tumor size was determined using the size of the resection loop or biopsy forceps as a reference.
Results:
Of all suspected new and recurrent bladder tumors 22% were benign or inflammatory lesions. A total of 167 patients with a new urothelial tumor and 214 recurrences in 166 patients were registered during the study period. Compared to new tumors, recurrences were more often noninvasive (88% vs 67%, p <0.001), more often 10 mm or less in diameter (63% vs 18%, p <0.001) and more often multifocal (55% vs 38%, p <0.01). New and recurrent tumors had a median size of 20 and 8 mm, respectively.
Conclusions:
The absolute majority of suspected bladder tumor recurrences are benign or low grade noninvasive malignant tumors and are less than 10 mm in diameter. This finding suggests that there is great potential for cost reductions when a significant proportion of patients with suspected recurrences after treatment of low grade tumors could undergo biopsy and fulguration using local anesthesia in the office instead of general anesthesia.

