Rare case of Lichen Planus in patient on Pembrolizumab reported

Punjab: A recent case study published in Indian Dermatology Online Journal described developing a rare immune-related adverse side effect in a patient receiving pembrolizumab.

The case in question is of a 54-year-old female who developed pembrolizumab-induced lichen planus while receiving pembrolizumab to manage lung metastasis from squamous cell carcinoma of the buccal mucosa. The lichen planus responded to acitretin, and pembrolizumab was continued safely.

Pembrolizumab is the first anti-programmed death protein-1 agent approved by the US FDA (Food and Drug Administration). It has shown efficacy in lung cancer, melanoma, and other advanced solid tumours and hematologic malignancies. Several dermatological side effects include psoriasis, lichenoid skin reactions, vitiligo, maculopapular rash, pruritus, and rarely life-threatening conditions like bullous pemphigoid, drug rash with eosinophilia, Stevens-Johnson syndrome, and systemic symptoms have been reported.

The 54-year-old female presented with violaceous papules over the feet and mucosal lesions after the start of treatment with pembrolizumab after pulmonary metastasis detection on PET-CT. The consecutive scans conducted every six months revealed a constant regression of the underlying metastatic lesion with immunotherapy.

Pembrolizumab was continued in the patient after the development of lichenoid rash, which increased in severity in the form of ulcerations over soles and oral erosions. Acitretin helped to achieve remission in lichen planus, thus allowing pembrolizumab to be continued safely.

"Although none of the Indian studies has reported lichenoid reactions or lichen planus as a cutaneous adverse drug reaction due to pembrolizumab, lichen planus pemphigoid following pembrolizumab and nivolumab have been reported otherwise," Aditi Bansal, Deep Hospital, Ludhiana, Punjab, India, and colleagues wrote in their case report.

Dr. Bansal and the team reported, "Remission in lichen planus was achieved with acitretin, and pembrolizumab was continued safely for six months. Unfortunately, the patient succumbed to infection with COVID-19 in January 2022 during the third wave in India, as she had developed COVID-19 pneumonia.

"All the immune checkpoint inhibitors can induce dermatological adverse events, and with their rising use to manage malignancies, greater awareness is required among dermatologists to diagnose, manage, and report more such cases," the team concluded.

Reference:

Bansal, Aditi; Singla, Ankur1; Paul, Davinder2; Kaur, Sukhjot1. Pembrolizumab-Induced Lichen Planus: A Rare Immune-Related Adverse Side Effect. Indian Dermatology Online Journal 14(3):p 391-394, May–Jun 2023. | DOI: 10.4103/idoj.idoj_377_22