Tocilizumab-associated oral ulcerations: a case report and scoping review

Tocilizumab (TCZ) is an interleukin-6 receptor inhibitor used in the treatment of rheumatoid arthritis and other inflammatory disorders. Oral ulcerative events have been described as an infrequently reported and potentially underrecognized effect of TCZ, but their clinical characteristics, frequency, and relationship to treatment remain incompletely characterized. This study aimed to map and characterize the available clinical evidence on oral ulcerative events reported during TCZ treatment and to present a clinical case.

A scoping review was conducted and reported in accordance with PRISMA-ScR guidelines. Peer-reviewed studies reporting oral ulceration, stomatitis, aphthous ulceration, or related oral mucosal events in adults receiving TCZ were included. A clinical case of recurrent oral ulceration temporally associated with TCZ therapy was also described.

Seventeen studies were included, comprising six clinical trials, five observational studies, and six case-report publications. Oral events were variably reported as oral or mouth ulceration, stomatitis, aphthous ulceration, or mucosal ulceration. Detailed information regarding lesion morphology, anatomical distribution, time to onset, duration, and resolution was frequently unavailable, particularly in clinical trials and observational studies. Reported events represented distinct clinical patterns, including newly occurring treatment-emergent events, recurrence following rechallenge, and persistence, lack of therapeutic response, or worsening of pre-existing disease-related ulceration. In the present case, recurrent painful oral ulcerations appeared approximately 24 h after the first TCZ injection and recurred following subsequent doses. Their frequency and severity gradually decreased following multidisciplinary management and subsequent discontinuation of TCZ, with complete resolution reported at the latest follow-up, nine months after TCZ withdrawal.

Oral ulcerative events are infrequently reported during TCZ therapy and may be underrecognized; however, the available evidence is heterogeneous and does not establish a uniform clinical phenotype or a definitive causal relationship. Pre-existing disease-related ulceration should be distinguished from newly occurring treatment-emergent events. Careful assessment of temporal relationships, underlying disease, concomitant therapies, and alternative etiologies is important when evaluating oral ulceration in patients receiving TCZ.