## 5 Conclusions  
To our knowledge, this work is the first to evaluate the combination of FTIR imaging of tissue samples with chemometric methods for the discrimination of responders and non-responders patients to chemotherapy in MIBC. The development of this technique, alone or in combination with molecular biology, could guide the therapeutic strategy by targeting the indication for neoadjuvant chemotherapy to responders only.  
**Supplementary Materials:** The following are available online at [[https://www.mdpi.com/article/10.3390/](https://www.mdpi.com/article/10.3390/)]([https://www.mdpi.com/article/10.3390/](https://www.mdpi.com/article/10.3390/)) cancers14010021/s1, Figure S1: Whole dataset after the pre-processing step that includes reduction on the 800-1800 cm\({}^{-1}\) spectral range and EMSC. The spectrum in the dotted line corresponds to the target spectrum (exhibiting vibrations associated with the protein content, such as Amide I and Amide II bands but also paraffin signal around 1450 cm\({}^{-1}\)) and the grey area the maximal variations of intensity observed at each wavenumber. EMSC aims at neutralizing the variability of the paraffin signal, eliminating outlier spectra, and normalizing the data according to the target spectrum.  
**Author Contributions:** [PERSON] and V.G. performed the infrared acquisition and data processing of the samples, [PERSON], V.V. and O.P. performed study concept, design, and writing of the paper, [PERSON]-C.E., P.B. and S.L. performed review and revision of the paper, [PERSON] provided technical and material support, J.-F.C., I.B., D.C. and P.V. participated to the interpretation of the data. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This study was possible thanks to the financial support of INSERM via the ITMO Cancer and ITMO Technologies pour la Sante coordinated by AVIESAN (National Alliance for Life Sciences & Health), within the framework of the Cancer Plan (France).  
**Institutional Review Board Statement:** This retrospective study was led from samples of four different centers in France (Jean Godinot (Reims), Reims University Hospital, Institute Courlancy (Reims), and La Pitie Salpetriere University Hospital (Paris)) originating from patients treated between January 2012 and October 2016.). The samples were obtained from the tumor banks of these institutes in agreement with the head of the pathology departments concerned. The ethical approval number was waived due to the fact that the period of inclusion (October 2016) was before the application of the Jarde law in France.  
**Informed Consent Statement:** Patient consent was waived due to the fact that the period of inclusion (October 2016) was before the application of the Jarde law in France, relating to the protection of individuals within the framework of biomedical research projects. The booklet received by the patients when they entered a health establishment included an indication of no objection to the use of their samples for research purposes.  
**Data Availability Statement:** The datasets used and analyzed during the current study are available from the corresponding author on reasonable request.  
**Acknowledgments:** The authors warmly thank [PERSON] from the Hippocrate Pathology Center (Bezannes, France) for providing part of the tissue samples, and [PERSON] for data processing assistance.  
**Conflicts of Interest:** The authors declare no conflict of interest.