Characteristics of appendicitis after immune checkpoint inhibitor therapy among cancer patients

Abstract

Immune checkpoint inhibitor (ICI) therapy has revolutionized cancer care but is associated with immune-related adverse events (irAEs). Recent case reports raised the concern that acute appendicitis may be an irAE. In this study, we sought to describe the disease course of post-ICI therapy appendicitis and its associated complications. MethodsAdult patients who had an International Classi cation of Diseases code for appendicitis within the rst 2 years after initiating ICI therapy from January 2010 to April 2021 and who had imaging evidence of appendicitis were studied retrospectively. Results13,991 patients were identi ed who had ICI exposure during the study period, 44 had codes for appendicitis, 10 of whom met the inclusion criteria. Their median age at the time of diagnosis was 59 years. The median time from ICI therapy initiation to appendicitis onset was 188 days. The most common presenting symptoms were abdominal pain (70%) and fever (40%).Abscesses were present in two patients, and a perforation was present in one. All 10 patients received broad-spectrum antibiotics. Five patients needed surgery or interventional radiology drainage. Nine patients had resolution of appendicitis symptoms after treatment. ConclusionPost-ICI therapy appendicitis is rare but presents similarly to and has similar complications rates as conventional appendicitis. Appendectomy remains the mainstay of treatment, but its use can be limited in cancer patients. The decision to continue ICI therapy remains at the discretion of the clinician. Further studies are needed to bring awareness to and advance the understanding of this clinical entity.

Intra-abdominal infections survival guide: a position statement by the Global Alliance For Infections In Surgery

“…Acquired conditions include human immunodeficiency virus/acquired immunodeficiency syndrome, patients with malignant liquid or solid tumors undergoing chemotherapy [142], solid-organ transplant (SOT) recipients, or patients with inflammatory or rheumatologic disease treated with immunomodulators [143]. Notably, immune checkpoint inhibitor therapy has been associated rarely with the development of acute appendicitis [144].…”

An updated review of gastrointestinal toxicity induced by PD-1 inhibitors: from mechanisms to management

“…The clinical manifestations (e.g., abdominal pain and fever) and imaging manifestations (e.g., appendiceal dilatation and wall thickening) of appendicitis after PD-1/PD-L1 inhibitors are similar to those of conventional appendicitis, so the current management strategies are largely similar ( 116 ). Despite the complexity of cancer patients, appendectomy remains the mainstay of treatment.…”