Presentation Authors: Aeen Asghar*, Daniel Parker, Thomas McGowan, Richard Greenberg, Marc Smaldone, David Chen, Rosalia Viterbo, Robert Uzzo, Evan Bloom, Daniel Geynisman, Eric Ross, Elizabeth Plimack, Philip Abbosh, Matthew Zibelman, Alexander Kutikov, Philadelphia, PA
Introduction: Concern for discordance between endoscopic evaluation and final pathology drives current clinical management of patients deemed appropriate candidates for radical cystectomy (RC). Yet some 30% of patients who undergo neoadjuvant chemotherapy (NAC) prior to RC do not harbor detectable malignancy within the bladder at the time of surgery. Our objective was to better understand reliability and shortcomings of cystoscopic evaluation in RC candidates utilizing a protocol where all patients undergoing RC at our institution first receive a Systematic Endoscopic Evaluation (SEE).
Methods: Patients undergoing RC for urothelial carcinoma (UC) at our institution are enrolled in a prospective, non-randomized, IRB-approved cohort study to evaluate reliability of SEE in predicting pT0 bladder cancer. SEE consists of rigid cystoscopy with targeted biopsy (and transurethral resection with loop after amendment) of visible tumor and/or tumor bed/scar, plus two additional random biopsies are performed immediately prior to RC. A standardized bladder map diagram is used to index cystoscopic findings. The endoscopic findings and transurethral biopsy results are then compared to the final pathologic cystectomy specimen. This ongoing trial is planned to end when 99 patients have been recruited or an early stopping point for futility is met.
Results: To date, 52 patients consented to the study, and 49 have received RC. SEE involved targeted biopsies in 35 and TUR resection, after protocol amendment, in fourteen. 31 (63%) underwent RC for MIBC, while 18 (37%) had high-risk NMIBC. 28 (57%) received NAC. Upon extirpation, pT0, pTis, pTa, pT1, pT2, pT3, and pT4 UC was found in 11 (22%), 9 (18%), 3 (6%), 3 (6%), 6 (12%), 10 (20%), 7 (14%), respectively. On SEE, 24 (49%) patients demonstrated no visual nor pathologic evidence of UC. Of these 24 cT0 patients, 10 patients had concordant pT0 findings, while 7 harbored undetected carcinoma in situ or pTa disease. Meanwhile, another 7 patients revealed evidence of residual â‰¥pT2 disease (pT2=2, pT3=3, pT4a=2), resulting in a false negative rate of 29% for cT0 SEE in detecting â‰¥pT2.
Conclusions: Our first of its kind prospective protocol reveals that SEE can miss nearly 30% of â‰¥pT2 urothelial pathology. These data provide unprecedented insights into limitations of accurate endoscopic diagnosis of pT0 disease and serve as a jumping off point for improvement of non-extirpative strategies for diagnosis of malignant submucosal bladder tissue.