Tisotumab vedotin-associated Stevens-Johnson syndrome in a patient with recurrent vulvar cancer: Vulnerability and antibody drug conjugate toxicity considerations.

Background: Severe adverse events from novel cancer therapies are significant concerns, particularly in patients with recurrent disease who have limited treatment options and reduced reserve. We present a rare case of Stevens Johnson Syndrome (SJS) after initiation of tisotumab vedotin (TV) in an elderly patient with recurrent vulvar squamous cell carcinoma (SCC). Case: A 76-year-old female with recurrent poorly differentiated vulvar SCC presented with fever, painful rash, and altered mental status 11 days after starting TV. Medical history is notable for HIV (undetectable viral load on antiretroviral medication). Examination revealed a desquamating rash in the bilateral axillae and groin. She was admitted for urosepsis secondary to an obstructing right kidney stone. Two days later, her rash progressed with a positive Nikolsky sign and lesions found in the mouth, axillae, and back. Histopathology frozen section demonstrated SJS and her clinical picture was consistent with toxic epidermal necrolysis (TEN) with a mortality risk of > 90%. The patient and family elected comfort measures. She died on hospital day four. Conclusion: A phase III trial on patients with recurrent cervical cancer reported SJS in three patients (representing 1.2% of patients on TV), with one fatal outcome. Given that the median age was 51 and frailer patients were excluded, this trial may underestimate toxicity in a broader population. Multidisciplinary management is essential for frail patients with comorbidities receiving medications such as TV. Further research is necessary to improve outcomes of patients who suffer SJS/TEN and other serious adverse events after TV as its use expands.