New oncological approaches using immune checkpoint inhibitors aim to reinvigorate lymphocytes against the tumor. The prognosis of cancer has been significantly improved by these treatments, which nonetheless lead to a new spectrum of immune-related side effects. The most frequent are skin rash, colitis, thyroid dysfunction, hypophysitis, hepatitis and pneumonitis. Early detection of these toxicities is crucial to determine the etiology and to introduce a temporary immunosuppressive therapy, allowing resolution of toxicity in most of cases. A multidisciplinary team is essential for optimal management.