We thank the patients and their families. We thank the Clinical Research Unit (CRU) at the London Regional Cancer Program (LRCP) for their support in running the trial. We thank the staff at the CRCHUM animal facility and the Immunomonitoring core facility at the CRCHUM for their help with the experiments. We acknowledge the support of the Rosalind and Morris Goodman Cancer Institute Research Support, the Single Cell Imaging and Mass Cytometry Analysis Platform and the Histology Core facilities at McGill University. The clinical trial was funded by a grant from the Lotte and John Hecht Memorial Foundation awarded to S.M.V. and J.P.B., a grant from the Division of Medical Oncology at Western University awarded to J.G.L. and S.M.V. and a Canadian Cancer Society Impact grant supported by the Lotte and John Hecht Memorial Foundation awarded to B.R., S.M.V. and A.E. The laboratory of B.R. for ancillary analyses and biobanking was funded by Institute du Cancer de Montréal, Terry Fox Marathon of Hope clinician-scientist award. The laboratory of S.M.V. for ancillary analyses and biobanking was funded by a project grant from the Canadian Institute of Health Research (CIHR) (MOP no. 389137) and a LRCP Catalyst Grant Program, Keith Samitt Translational Research grant. Metagenomics sequencing was funded by ONCOBIOME, project number 825410 (Gut OncoMicrobiome Signatures associated with cancer incidence, prognosis and prediction of treatment response). B.R. received salary support from Fonds de Recherche du Quebec Santé. S.M.V. received salary support from the Ontario Institute of Cancer Research (OICR) and The London Health Sciences Foundation Helen and Andy Spriet funds. M.M. reports salary support from Seerave foundation. A.E. reports support from CIHR, Royal College of Physicians and Surgeons of Canada. Metabolomics studies were performed at the Medical Research Council (MRC)-National Institute of Health Research (NIHR) National Phenome Centre at Imperial College London; this center receives financial support from the MRC and NIHR (grant number MC_PC_12025). B.H.M. is the recipient of an NIHR Academic Clinical Lectureship (CL-2019-21-002). The Division of Digestive Diseases and MRC-NIHR National Phenome Centre at Imperial College London receive financial and infrastructure support from the NIHR Imperial Biomedical Research Centre based at Imperial College Healthcare NHS Trust and Imperial College London. B.D. acknowledges support from an NSERC Postdoctoral Fellowship Award (PDF-558010-2021). K.F.A. acknowledges support from an American Urological Association Research Scholar Award. Cytofluorimetric analyses in the laboratory of S.M.M.H. were funded through a project grant (PJT – 156295) from the CIHR. I.R.W. reports support from the Terry Fox Research Institute (grant 1084), CIHR (PJT-178341 grant), Canada Research Chairs Program, donations from K. J. Baggs and donations from the Rachel and Jason Schwartz Family Foundation. Financial support was also obtained from the Quebec Cancer Consortium and the Ministère de l’Économie et de l’Innovation du Québec through the Fonds d’accélération des collaborations en santé and the Victor Liu McGill Interdisciplinary Initiative in Infection and Immunity (MI4) initiative. This research was enabled, in part, by support provided by Calcul Québec (www.calculquebec.ca), SHARCNET (www.sharcnet.ca) and Compute Canada (www.computecanada.ca). L.D. was supported by RHU5 ANR-21-RHUS-0017 IMMUNOLIFE; EU-H2020, project no. 825410, project ONCOBIOME, Gut OncoMicrobiome Signatures associated with cancer incidence, prognosis and prediction of treatment response; and the SIGN’IT ARC Foundation.