A case report of total epidermal necrosis following mirvetuximab soravtansine extravasation.

Background: Mirvetuximab soravtansine (MIRV) is an antibody-drug conjugate (ADC) approved for the treatment of platinum-resistant ovarian cancer. We report the first known case of total epidermal necrosis secondary to MIRV extravasation, representing an unreported adverse event. Case: A 74-year-old woman with recurrent high-grade serous carcinoma of the peritoneum who developed extensive soft tissue injury following peripheral intravenous extravasation of MIRV. Despite immediate cessation of the MIRV infusion and conservative management, the patient developed progressive cutaneous toxicity, including full-thickness epidermal necrosis, requiring an 18-day hospitalization and wound care at a regional burn center. No surgical intervention was required. Management included topical therapies, reduced dressing changes, systemic antibiotics, and vitamin D3. Following discharge, a central venous access device was placed, and she completed subsequent MIRV cycles without further complications. Conclusion: This case underscores the potential for severe soft tissue injury from MIRV extravasation, despite its lack of vesicant labeling. Contributing factors may include the instability of its disulfide linker and the cytotoxicity of the DM4 payload. As MIRV and other ADCs become more widely used in clinical settings, establishing clear protocols for recognizing and managing extravasation is essential. Central venous access and standardized documentation may mitigate risk. Increased awareness and reporting are needed to inform clinical guidelines and ensure safe administration of ADC therapies.