CRP and lung cancer: A multicenter retrospective study of 107 advanced lung cancer patients with checkpoint inhibitor-related pneumonitis (CIP) found elevated IL-6 and CRP levels at the time of ICI rechallenge were significantly associated with higher CIP recurrence rates (36), which suggests that patients with elevated IL-6 and CRP may be in an inflammatory state during rechallenge, making them more susceptible to CIP recurrence.