Multiple high-grade and rare immune-related adverse events in a colon cancer patient with genomic and cytokine profiling.

Immune-related adverse events (irAEs) are a potential side effect of taking immunotherapy treatment for cancer. We report a case of a patient with a highly mutated form of metastatic colon cancer who developed five unique and severe irAEs while receiving immunotherapy. The patient developed inflammation of the lymph nodes, lungs, pituitary gland, thyroid and spinal cord. Genetic testing showed that the tumor was highly mutated (43 Muts/Mb). Analysis of cell signaling proteins called cytokines revealed that MMP-9 sharply increased before the onset of lymphadenitis and Ang-1 sharply increased after its resolution. Further research is needed to understand the relationship between highly mutated colon cancer and irAEs as well as the role of cytokines in predicting the onset and resolution of irAEs.