Relevance of fresh frozen sections (FFS) for carcinoma in situ (CIS) detection in radical cystectomy for bladder cancer.

Abstract

667 Background: Radical cystectomy is the standard of care for muscle invasive bladder cancer after neoadjuvant chemotherapy. Complete resection is mandatory. To detect CIS in the ureter or urethra FFS are performed and sequential resections of the ureter or urethrectomy are performed in case of positive findings. In this retrospective analysis we highlight the frequency of CIS in FFS and locations of recurrences in patients with CIS in the final specimen. Methods: We retrospectively analyzed patients undergoing radical cystectomy between 2015 und 2024. CIS in the urethra and ureters was analyzed in FFS and final pathologic results. In patients with CIS in the final pathology recurrence patterns were analyzed. Results: In 369 patients CIS was detected in 17 (4,9%) patients. After sequential resection of the urethra or ureter a complete resection in FFS was demonstrated in 13 (3,5%) of the patients. In 4 patients (1,1%) persistent CIS and in another 4 (1,1%) patients CIS is described after negative FFS. In five and three patients CIS was located in the ureter and urethra. 5 patients had either BCG or HIVEC for local treatment. Within 2 years 4(50%) of the patients developed recurrent disease. In none local recurrence but retroperitoneal lymph nodes, hepatic, pulmonary and or bone metastases were detected. Conclusions: The detection of CIS in FFS is rare, time and cost consuming. The oncologic benefit is limited as in all cases distant metastases developed. According to our results the routine use of FFS to detect CIS must be questioned.