Control computerized tomography in neoadjuvant chemotherapy for muscle invasive urinary bladder cancer has no value for treatment decisions and low correlation with nodal status. (2nd November 2021) - Tenninge, S.
Abstract: Background: Control computerized tomography (cCT) is routinely used in many cystectomy centres before the final treatment cycle in patients with muscle-invasive urinary bladder cancer (MIBC) undergoing neoadjuvant chemotherapy (NAC). This is for evaluating response or nonresponse to NAC treatment. In a real-world retrospective cohort, we intended to evaluate the frequency of changed individual treatment strategies following cCT and to investigate any discrepancies between cCT-results on nodal staging and final pN-stages. Methods: We performed a retrospective data-based, multicenter study of 242 MIBC-patients, staged cT2N0M0-cT4aN0M0, having undergone NAC and radical cystectomy (RC) between 2008 and 2019 at four Swedish cystectomy centres. Statistical analysis was performed using IBM SPSS statistics 26. Results: Overall, 139/242 patients were examined with cCT. Six patients were staged as progressive at cCT and 5/139 (3.6%) underwent a change of previously planned treatment strategy. 2/6 patients with suspected progression (33%) did not change strategy and underwent all preplanned NAC-cycles plus RC. Only 1/6 patients assigned as progressive at the cCT, showed progression in the postoperative pathology specimen. In total 133/139 patients were considered being without progress on cCT, yet 28/133 (21%) presented with nodal progression at postoperative pathology examinations. Only 1/29 patients with histopathologically verified nodal dissemination were detected with cCT, thus 28/29 (96.6%) with pN + were undetected. The sensitivity for cCT to predict pTNM was 17% CI [0%–64%] and the specificity was 78% CI [71%–86%]. Conclusions: CCT prior to the final treatment cycle of NAC in MIBC, leads to a low percentage of treatment strategy changes and cCT cannot accurately predict pN-status.