title: Tumor infiltrating lymphocytes in gastrointestinal tumors: Controversies and future clinical implications.
abstract: Chronic inflammation following infections, autoimmune diseases or exposure to environmental irritants plays a crucial role in tumor development and influences the host immune response to neoplastic cells. The presence of an anti-tumor immune infiltrate is often associated with better outcomes in gastro-intestinal primary cancers, particularly in those with high microsatellite instability (MSI-H). Immunotherapeutic drugs inhibiting the PD-1 and PD-L1 pathway showed promising results in the treatment of these patients in the metastatic setting. The aim of this review is to resume the role tumor infiltrating lymphocytes (TILs) play in gastrointestinal tumors, underlining their potential value as a prognostic and predictive biomarker. TILs assessment could identify subsets of patients with high extent of TILs and better prognosis, that could be spared from adjuvant systemic treatments. Immune infiltration parameters might be additional predictors of a greater benefit from the immunotherapy with the immune checkpoint blockade.
authors.affiliation: Molecular Immunology Unit, Institut Jules Bordet and Université Libre de Bruxelles, Boulevard de Waterloo, 127 1000 Brussels, Belgium. Electronic address: czsolinas@gmail.com.
authors.forename: Cinzia
authors.initials: C
authors.lastname: Solinas
authors.affiliation: Medical Oncology, University of Cagliari, Policlinico Universitario ss 554 bivio Sestu km 4.5, Monserrato, CA, Italy. Electronic address: grazia.pusole@gmail.com.
authors.forename: Grazia
authors.initials: G
authors.lastname: Pusole
authors.affiliation: Medical Oncology, University of Cagliari, Policlinico Universitario ss 554 bivio Sestu km 4.5, Monserrato, CA, Italy. Electronic address: lau.demi@tiscali.it.
authors.forename: Laura
authors.initials: L
authors.lastname: Demurtas
authors.affiliation: Medical Oncology, University of Cagliari, Policlinico Universitario ss 554 bivio Sestu km 4.5, Monserrato, CA, Italy. Electronic address: marcopuzzoni@gmail.com.
authors.forename: Marco
authors.initials: M
authors.lastname: Puzzoni
authors.affiliation: Medical Oncology, University of Cagliari, Policlinico Universitario ss 554 bivio Sestu km 4.5, Monserrato, CA, Italy. Electronic address: roboa@hotmail.it.
authors.forename: Roberta
authors.initials: R
authors.lastname: Mascia
authors.affiliation: Medical Oncology, Skåne University Hospital, Lund, Sweden. Electronic address: Gilberto.Morgan@Skane.se.
authors.forename: Gilberto
authors.initials: G
authors.lastname: Morgan
authors.affiliation: Medical Oncology, UNIVPM, Ancona, Italy. Electronic address: riccardo.giampieri81@gmail.com.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Giampieri
authors.affiliation: Medical Oncology, University of Cagliari, Policlinico Universitario ss 554 bivio Sestu km 4.5, Monserrato, CA, Italy. Electronic address: marioscartozzi@gmail.com.
authors.forename: Mario
authors.initials: M
authors.lastname: Scartozzi
mesh_terms: D000818:Animals; D014408:Biomarkers, Tumor / Q000032:analysis; D005770:Gastrointestinal Neoplasms / Q000737:chemistry / Q000276:immunology* / Q000628:therapy; D006801:Humans; D007167:Immunotherapy; D016246:Lymphocytes, Tumor-Infiltrating / Q000276:immunology*; D011379:Prognosis
chemical_list: D014408:Biomarkers, Tumor
keywords: Gastrointestinal tumors; Immunotherapy; Microsatellite instability; Prognosis; Tumor infiltrating lymphocytes