Oral lichenoid lesions in association with immunotherapies: a report of two cases and a review of published work

BACKGROUND: A variety of drug-induced oral lichenoid lesions (OLLs) have been extensively reported in the literature, but the diagnosis and recognition of OLLs remain challenging for clinicians. To date, a wide range of drugs, including anti-inflammatory drugs, antihypertensives, antibiotics and others, have been suggested to cause OLLs with different presentations. To the best of our knowledge, immunotherapies are becoming increasingly preferred treatments for systemic diseases. At the same time, oral adverse events, including OLLs due to immunotherapies, are not widely appreciated. CASE PRESENTATION: We present two cases of OLLs in patients with ankylosing spondylitis and follicular lymphoma in whom different immunotherapies, including sulfasalazine and obinutuzumab, were used. The oral lesions presented reticular, atrophic, and ulcerated patterns. The patients' oral lesions improved after the administration of glucocorticoid therapy and the cessation of immunoregulatory treatment. CONCLUSION: This article describes two rare and representative cases related to OLLs induced by immunotherapies to update our knowledge of the drugs used by patients and improve the management, recognition and reporting of oral adverse events.