Checkpoint Inhibitor in a Melanoma Patient With Polyendocrinopathy and Gangrenous Gallbladder With a Mass

Checkpoint inhibitors are introduced as a therapy for clinical use for various cancers, and clinicians are documenting new adverse effects. This is the first case report to the best of our knowledge of a patient on checkpoint inhibitor presenting with both polyendocrinopathy and gangrenous gallbladder disease with a mass negative for malignancy.71-year-old man presented four years after his initial diagnosis of stage IV, unresectable, non-ulcerated, acryl, lentiginous malignant melanoma. On presentation, he had gangrenous cholecystitis and was treated with laparoscopic cholecystectomy. Incidentally, the patient was diagnosed two years ago with hypothyroidism, hypophysitis, secondary adrenal insufficiency, and pneumonitis, each suspected to be secondary to treatment with pembrolizumab (Keytruda), a monoclonal anti-programmed cell death-1 antibody. He presented to the emergency department for a gallbladder attack and underwent successful laparoscopic cholecystectomy. The intra-operative finding on opening the specimen was an unusual looking exophytic mass but was negative for malignancy on pathology report and reported as gangrenous cholecystitis. His clinical condition before and after surgery was complicated by worsening comorbidities thought to be secondary to pembrolizumab therapy, which required acute care hospitalizations in the weeks before and after his presentation with cholecystitis. The patient had a few admissions from other co-morbidities post-surgery and was doing better. Immunotherapy with pembrolizumab may have secondary and tertiary effects with unusual presentations that are difficult to interpret for the primary oncology team and even tougher to do for community physicians who may subsequently encounter these patients. The relationship of this patient's comorbidities with immune-related adverse events was not apparent until record requests were conducted after surgery and are still not entirely clear after a literature review. More data is needed to guide decision algorithms and to predict which patients may experience these effects.