Disease stabilization with pembrolizumab for metastatic acral melanoma in the setting of autoimmune bullous pemphigoid.
BACKGROUND
To date, patients with pre-existing autoimmune conditions have been excluded from immunotherapy trials out of concern for severe autoimmune exacerbations.


METHODS
We describe the first case of a patient with metastatic cKIT mutated acral melanoma, brain metastasis, and pre-existing severe autoimmune bullous pemphigoid (BP) with stable and asymptomatic disease 10 months after treatment with pembrolizumab. The patient experienced severe BP exacerbation after therapy with ipilimumab requiring systemic immune suppression, but nonetheless pembrolizumab was administered on further disease progression.


CONCLUSIONS
This case suggests that pembrolizumab may confer more benefit than risk even in patients with known severe autoimmune conditions who require intermittent systemic immunosuppression.
Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY USA.|Department of Dermatology, Columbia University College of Physicians and Surgeons, New York, NY USA.
Kristen M
KM
Beck
Department of Dermatology, Icahn School of Medicine at Mount Sinai, New York, NY USA.
Joanna
J
Dong
Department of Dermatology, Columbia University College of Physicians and Surgeons, New York, NY USA.
Larisa J
LJ
Geskin
Department of Dermatology, Columbia University College of Physicians and Surgeons, New York, NY USA.
Vincent P
VP
Beltrani
Department of Dermatology, Icahn School of Medicine at Mount Sinai, New York, NY USA.|Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, NY USA.
Richard G
RG
Phelps
Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY USA.
Richard D
RD
Carvajal
Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY USA.
Gary
G
Schwartz
Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY USA.
Yvonne M
YM
Saenger
Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY USA.
Robyn D
RD
Gartrell
Anti-PD1; Autoimmunity; Bullous pemphigoid; Immune-related adverse events [irAEs]; Immunotherapy; Metastatic Melanoma; Pembrolizumab