Abstract : In the last ten years, immune checkpoint inhibitors (ICI) have transformed the cancer treatment landscape. Due to their immunomodulating properties, the ICIs have a distinctive toxicity profile, resulting in autoimmune-like manifestations termed immune-related adverse events (irAEs). This irAE can range from a mild asymptomatic state to severe life-threatening conditions involving various organs, including endocrinopathies, which need clinical attention. The present case series, case one, represents the development of hypophysitis, though rare, with nivolumab, which is yet a crucial diagnosis. Cases two, three, four, and five highlight the varied spectrum of development of hypothyroidism, thereby underscoring the need for regular biochemical monitoring in patients on immunotherapy. Given the rapidly expanding indication for the use of ICIs, future research must assess the long-term effects of ICIs on thyroid function to understand thyroid irAEs better. Further research is mandated to analyze the disease causation mechanism and determine the reversibility once the drug is stopped.