Immune-related cholecystitis following combination therapy with nivolumab and ipilimumab in a patient with metastatic melanoma: a case report and literature review

Immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment but are associated with a range of immune-related adverse events (irAEs). While gastrointestinal irAEs are well-recognized, cholecystitis remains an exceedingly rare and poorly understood complication. We present a rare case of ir-cholecystitis in a patient with melanoma following combination therapy with nivolumab and ipilimumab. The patient developed acute gastrointestinal symptoms and fever shortly after the second dose, leading to hospitalization. Laboratory evaluation and imaging studies confirmed cholecystitis without gallstones, while given the timing, clinical context, and imaging findings, immune-related cholecystitis was suspected. Initial conservative management with intravenous hydration, antibiotics, and bowel rest was insufficient, necessitating corticosteroid therapy, which led to rapid clinical improvement. This case underscores the importance of considering rare irAEs, such as ir-cholecystitis, in patients receiving ICIs - even in the absence of classical symptoms. Due to the scarcity of reported cases and the absence of established treatment guidelines, management remains empirical. Our experience, together with a review of the available literature, supports the potential role of corticosteroids in refractory cases, though further research is needed to guide standardized therapeutic approaches.