Background:
Immune checkpoint inhibitors have provided significant clinical benefits to many patients with advanced
cancer; however, severe immune-related adverse events (irAEs) have occurred. Detecting and treating irAEs early could improve patient prognoses. Therefore, clinicians and patients should understand that these irAEs exist, especially those that are rare and serious. Case Presentation: In this report, an 86-year-old male patient, diagnosed with metastatic
gastric cancer involving the peritoneum and retroperitoneal lymph nodes was treated with 5-cycle
pembrolizumab therapy (100 mg q 2 weeks), achieving a partial response. However, the patient developed Grade 3 cholestatic
hepatitis and delayed
pneumonia 10 days and 2 months after the final
pembrolizumab dose, respectively. After discontinuing the
pembrolizumab therapy and excluding
obstructive jaundice with imaging studies, the patient received
steroid therapy, with a gradual symptom improvement. However, the patient developed delayed
pneumonia with type 1
respiratory failure 1-month post-discharge. Several microbiologic tests were negative, and immune-associated
pneumonia was suspected, but we could not exclude an
opportunistic infection. The patient recovered with
steroids and
antibiotics and remained in partial remission 5 months after
pembrolizumab withdrawal. Conclusions: Cholestatic
hepatitis is a rarely reported toxicity of
immune checkpoint inhibitors, which should be suspected and addressed once
obstructive jaundice is ruled out. In addition, clinicians should be aware that irAEs can occur at any time in patients treated with
immune checkpoint inhibitors and that a timely diagnosis should be made.