Immune checkpoint inhibitors, which boost the immune system’s response against tumor cells, have transformed treatment for many advanced cancers, but short-term clinical trials and small observational studies have linked the medications with various side effects, most commonly involving the skin. A more comprehensive, population-level analysis now provides a thorough look at the extent of these side effects and provides insights on which patients may be more likely to experience them. The research was led by investigators at Massachusetts General Hospital (MGH) and is published in the Journal of the American Academy of Dermatology.