Fecal microbiota transplantation and its repercussions in patients with melanoma refractory to anti-PD-1 therapy: scope review

Abstract

Introduction: despite being extremely effective in some cases, up to 70% of patients with melanoma do not respond to anti-PD-1/PD-L1 (primary resistance) and many of the responders eventually progress (secondary resistance). Extensive efforts are being made to overcome this resistance through new strategies, especially aimed at modulating the intestinal microbiota. Objective: to assess whether fecal microbiota transplantation (FMT), associated with immunotherapy, is beneficial in the clinical course of patients with refractory melanoma. Methods: this is a scope review, based on studies collected on the MEDLINE, ScienceDirect, The Cochrane Library, Embase and BMJ Journals; using the terms: “Antibodies, Monoclonal”; “Drug Resistance, Neoplasm”; “Fecal Microbiota Transplantation”; “Host Microbial Interactions”; “Immunotherapy”; “Melanoma”; and “Microbiota”. Clinical trials, in English, with relevant data on the subject and fully available were included. A cut-off period was not determined, due to the limited amount of evidence on the topic. Results: crossing the descriptors allowed the identification of 342 publications and, after applying the eligibility criteria, allowed the selection of 4 studies. From the analyses, it was observed that a considerable part of those studied overcame resistance to immune checkpoint inhibitors after FMT, with better response to treatment, less tumor growth and increased beneficial immune response. Conclusion: it is noted that FMT favors the response of melanoma to immunotherapy, translated into significant clinical benefit. However, further studies are necessary for the complete elucidation of the bacteria and the mechanisms involved, as well as for the translation of new evidence to oncological care practice.

Causal Relationship between the Gut Microbiota and Haematological Malignancies: A Two-Sample Mendelian Randomization Analysis

“…Faecal microbiota transplantation (FMT) involves transferring the gut microbiota from a healthy donor to the patient's gastrointestinal tract to restore the patient's gut microbial system. FMT has been shown to be effective in the treatment of various diseases, including ulcerative colitis [46], type 1 diabetes [47], hepatic encephalopathy [48], liver cancer [49], and refractory melanoma [50]. FMT in AML can delay leukaemia progression [40], and autologous FMT can effectively restore the gut microbiota in acute leukaemia patients receiving chemotherapy and broad-spectrum antibiotics [51].…”