Sterile Neutrophilic Pseudomembranous Conjunctivitis Associated with Tisotumab Vedotin: Clinical and Cytological Evidence from Two Cases

Background Tisotumab vedotin-tftv (TV), an antibody-drug conjugate (ADC), represents a significant advancement in cancer therapy but carries the potential to induce ocular surface toxicity. Having encountered ocular side effects with TV and obtained intriguing findings from histological examination, we discuss the pathophysiology and management approaches. Cases: Two female patients with advanced cervical cancer receiving TV therapy developed pseudomembranous conjunctivitis after 2 to 3 doses. Both cases presented with conjunctival hyperemia and pseudomembrane formation on the tarsal conjunctiva. One case additionally exhibited multiple epithelial erosions on the inferior conjunctiva. Cytology of the pseudomembrane showed neutrophilic infiltration but no detectable microorganisms. This suggested an immune-mediated erosion, such as a tissue factor-mediated reaction in the conjunctival epithelium. Complete remission was achieved within two weeks with topical corticosteroids (dexamethasone eye drops: 4–5 times daily) and lubricants. In both cases, after achieving grade 0 by extending the treatment interval, re-treatment was performed; however, ocular side effects recurred in Case 1. Four days of prophylactic steroid eye drops failed to prevent side effects, but intensifying steroid eye drops allowed inflammation to resolve without sequelae. However, intraocular pressure increased after the seventh dose. In Case 2, after side effects appeared, TV administration was resumed with extended intervals and reduced dosage; no conjunctivitis side effects were observed under the recommended prophylactic protocol. Both patients have now completed the seventh dose. Conclusions TV may cause pseudomembranous conjunctivitis with conjunctival erosion characterized by non-infectious neutrophilic infiltration, suggesting off-target cytotoxicity. Further case accumulation is necessary for the appropriate management of TV-induced ophthalmic side effects.