Computerized tomography before the final treatment cycle of neoadjuvant chemotherapy or induction chemotherapy in muscle-invasive urinary bladder cancer, cannot predict pathoanatomical outcomes and does not reflect prognosis—results of a single centre retrospective prognostic study

BACKGROUND: Evaluating the routine of using control computer tomography (cCT) for determining the response status of muscle-invasive bladder cancer (MIBC) prior to final cycle of neoadjuvant chemotherapy (NAC) or induction chemotherapy (IC), in terms of predicting histopathological pTNM-staging and pathoanatomical responses/non-responses. Secondly, predicting two and three-year overall survival (OS). METHODS: Seventy-seven patients with localized MIBC (cT2-4aN0M0) and 3 patients with minimal nodal dissemination (cN1-2), undergoing NAC or IC and radical cystectomy (RC), the years 2006–2014 at Norrland university hospital in Umeå, Sweden. Baseline pre-cystectomy CTs and cCTs prior to final chemotherapy-cycle, were reviewed and underwent attempted RECIST-criteria categorization, into five response/non-response related subgroups (n=71). The diagnostic accuracy of cCT in comparison with pTNM was assessed using sensitivity, specificity, positive- and negative likelihood ratios. OS for 2 and 3 years was calculated, both in relation to histopathological pTNM-stages in all patients (n=80) and for the patients with cCT-evaluated categories (n=71). Multivariable analysis for OS, was performed in correlation to pTNM-stages firstly, and to radiological staging secondly. RESULTS: The sensitivity of cCT to predict non-responders according to pTMN was 64% and specificity 36%. The positive likelihood ratio=1 and the negative likelihood ratio =1. CT-evaluations couldn’t accurately predict pTNM-stages in terms of response/non-response. No statistically significant results were found in correlating cCTs with two and three-year OS. CONCLUSIONS: cCT prior to planned final preoperative chemotherapy-cycle in MIBC patients undergoing NAC or IC, has a poor correlation with pTNM and cannot predict pathoanatomical responses. Prediction of OS based on cCTs is unfeasible.