Is gut microbiome a predictive marker to response to immune checkpoint inhibitors?
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Immune checkpoint inhibitors (ICI) are changing the treatment of solid and hematologic malignancies and becoming an integral part of the management of cancer patients. Ipilimumab, a CTLA-4 inhibitor, was associated with significant survival benefit in metastatic melanoma [1]. In addition, PD-1 and PD-L1 inhibitors such as nivolumab, pembrolizumab and atezolizumab showed remarkable clinical responses in multiple cancer types ranging from 20 to 30% when used in monotherapy. These agents are approved by the US FDA in the management of various tumor types such as metastatic melanoma, non-small-cell lung cancer (NSCLC), renal cell carcinoma, classical Hodgkin's lymphoma, urothelial bladder carcinoma and...