## 5 Conclusions
(c) Statistical validation of the PLS-DA model by permutation testing (500 permutations; 2 components), Figure S4: Statistical validation of the PLS-DA model obtained for urinary volatile profile of (a) patients diagnosed with MIBC (stages \(\geq\) T2, \(n=10\)) and NMIBC (stage Ta/Tis, \(n=26\)), after variable selection (36 observations \(\times\) 486 variables), and (b) patients diagnosed with MIBC (stages \(\geq\)T2, \(n=10\)) and NMIBC (stage T1, \(n=17\)), after variable selection (27 observations \(\times\) 856 variables), by permutation testing (200 permutations; 2 components), Table S1: List of volatile compounds significantly altered in urine of BC patients compared to cancer-free controls and between different BC stages, including their retention time (RT), most abundant ions, NIST and experimental retention index (RI), R-match, CAS number and identification level, Table S2: Correlation coefficients and corresponding \(p\)-values computed between age and the set of metabolites found altered in urine of BC (\(n=53\)) compared to cancer-free controls (\(n=56\)), Table S3: List of five volatile metabolites found altered in urine of patients diagnosed with stage T1 (\(n=17\)) compared with stage Ta/Tis (\(n=26\)), Table S4: List of eight volatile metabolites found altered in urine of patients diagnosed with stages \(\geq\)T2 (n = 10) compared with stage Ta/Tis (\(n=26\)), Table S5: List of six volatile metabolites found altered in urine of patients diagnosed with stages \(\geq\)T2 (\(n=10\)) compared with stage T1 (\(n=17\)), Table S6: Pre-processing steps of GC-MS chromatograms of VOCs and VCCs performed in MZmine-2.52. **Author Contributions:** Conceptualization, P.G.d.P. and M.d.L.B. ; methodology, A.C., F.A. and A.R.L. ; software, J.P.; validation, J.P.; formal analysis, A.C. and J.P.; investigation, A.C. and J.P.; resources, P.G.d.P., M.d.L.B., C.J. and R.H.; data curation, J.P., A.C., C.C.-M. and M.C.M. ; writing--originaldraft preparation, J.P.; writing--review and editing, J.P. and P.G.d.P. ; visualization, A.C. and J.P.; supervision, P.G.d.P. and M.d.L.B. ; project administration, P.G.d.P. ; funding acquisition, P.G.d.P. All authors have read and agreed to the published version of the manuscript. This research was funded by FEDER-Fundo Europeu de Desenvolvimento Regional funds through the COMPETE 2020-Operacional Programme for Competitiveness and Internationalisation (POCI), by Portuguese funds through FCT-Fundacao para a Ciencia e a Tecnologia in the framework of the project POCI-01-0145-FEDER-030388-PTDC/SAU-SER/30388/2017. The study was conducted according to the guidelines of the Declaration of Helsinki and approved by the Ethics Committee of the Portuguese Oncology Institute of Porto (IPO Porto) (Ref. CESIPOFG-EPE:019/08). Informed Consent Statement: Informed consent was obtained from all subjects involved in the study. Data Availability Statement: Data available on request due to privacy restrictions. Acknowledgments: This work was also supported by the Applied Molecular Biosciences Unit-UCIBIO which is financed by national funds from FCT (UIDB/04378/2020). [PERSON] thanks FCT for her PhD fellowship (SFRH/BD/123012/2016). [PERSON] is the recipient of a fellowship from the project MindGAP, funded by the European Union (BM-1-GEBC-H2020-FETOPEN-2018-2020). Conflicts of Interest: The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.