[Lichen sclerosus induced by pembrolizumab]

Area of Science:

• Oncology
• Immunology
• Dermatology

Background:

• Pembrolizumab, a PD-1 inhibitor, treats various cancers but can trigger immune-related adverse events (irAEs).
• Immune checkpoint inhibitors (ICIs) have been linked to irAEs mimicking autoimmune conditions.
• Lichen sclerosus (LS) is a rare irAE associated with ICI therapy, predominantly observed in female patients.

Purpose of the Study:

• To report a case of lichen sclerosus (LS) in a lung cancer patient undergoing pembrolizumab treatment.
• To highlight the association between immune checkpoint inhibitors (ICIs) and the development of LS.
• To discuss management strategies and long-term implications for patients developing LS during ICI therapy.

Main Methods:

• Case report of a 44-year-old female patient with lung cancer.
• Review of literature on immune-related adverse events (irAEs) associated with pembrolizumab and other ICIs.
• Analysis of treatment outcomes for LS induced by immunotherapy.

Main Results:

• The patient developed lichen sclerosus (LS) during pembrolizumab treatment for lung cancer.
• High-potency topical corticosteroids were administered, resulting in favorable outcomes.
• Immunotherapy with pembrolizumab was continued without interruption.

Conclusions:

• Lichen sclerosus (LS) is a potential immune-related adverse event (irAE) associated with PD-1 inhibitors like pembrolizumab.
• Topical steroid therapy is an effective management strategy for ICI-induced LS, allowing continued immunotherapy.
• Patients with LS require vigilant monitoring for potential secondary malignancies, particularly squamous cell carcinoma.