Immune Checkpoint Inhibitor-Related Sjögren's Syndrome: An Ocular Immune-Related Adverse Event

Area of Science:

• Oncology
• Immunology
• Ophthalmology

Background:

• Metastatic human papillomavirus (HPV)-positive oropharyngeal cancer is a significant clinical challenge.
• Immune checkpoint inhibitors, such as pembrolizumab (anti-programmed cell death protein 1 [PD-1]), are increasingly used for cancer immunotherapy.
• Immune-related adverse events (irAEs) are known complications of PD-1 inhibitor therapy.

Purpose of the Study:

• To report a case of Sjögren's syndrome presenting as an isolated ocular irAE in a patient receiving pembrolizumab.
• To highlight the importance of recognizing and managing ocular irAEs in patients undergoing cancer immunotherapy.
• To demonstrate the efficacy of topical treatment for Sjögren's syndrome in this context.

Main Methods:

• A case study of a 67-year-old male with metastatic HPV-positive oropharyngeal cancer treated with pembrolizumab.
• Ophthalmologic evaluation including fluorescein staining and Schirmer testing.
• Serological testing for autoimmune antibodies (antinuclear and anti-SSb/La).
• Treatment with topical fluorometholone 0.1% and diquafosol 3%.

Main Results:

• The patient developed bilateral ocular dryness (keratoconjunctivitis sicca) eight months after initiating pembrolizumab.
• Diagnosis of Sjögren's syndrome was confirmed by positive serological markers.
• Complete resolution of ocular symptoms was achieved within one year with topical treatment.
• Sustained ocular improvement and favorable oncologic response observed over 3.5 years without systemic autoimmune complications.

Conclusions:

• Sjögren's syndrome can manifest as an isolated ocular irAE during pembrolizumab therapy for HPV-positive oropharyngeal cancer.
• Prompt ophthalmologic evaluation and appropriate treatment are essential for managing ocular irAEs.
• Recognizing Sjögren's syndrome as a potential irAE can prevent diagnostic delays and ensure continued effective cancer immunotherapy.