Refractory Immune Checkpoint Inhibitor-induced Colitis Improved by Fecal Microbiota Transplantation: A Case Report
Cong Dai, Wei-Xin Liu
Abstract
To the Editors, Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of metastatic malignancies1,2; ICIs target immune checkpoints such as cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4), programmed cell death 1 (PD-1), and programmed death-ligand 1 (PD-L1), thereby allowing T lymphocytes to kill cancer cells. Given their mechanisms of action, ICIs can trigger various organ-specific immune-related adverse events, including colitis.3,4 We successful used fecal microbiota transplantation (FMT) to treat a patient with severe ICI-induced colitis that was refractory to steroid and infliximab (IFX) therapy. A 64-year-old man, diagnosed with left lung squamous cell carcinoma in 2020 (Figure 1A) and treated with bevacizumab, paclitaxel, and cisplatin, presented 6 months later with recurrent stage 4, T2N1M1 metastatic disease involving the brain, spleen, adrenal glands, and pancreas (Figures 1B, C). Tislelizumab, an anti-PD-1 ICI, was started. Two months after starting tislelizumab, the patient...