Pembrolizumab induced scleroderma

Systemic sclerosis (SSc) is a rare connective tissue disorder. It is a chronic multisystem disease characterized by vascular dysfunction and progressive fibrosis of tissue, with skin hardening and thickening (known as scleroderma) being the hallmark of the disease. It tends to affect females more than males and has a higher prevalence in African American population with earlier onset and more severe disease. While scleroderma can be a manifestation of conditions other than SSC, the presence of skin thickening of the fingers, extending proximally to metacarpophalangeal joints is sufficient to classify a patient as having SSc. SSc treatment is challenging given the heterogeneity of the disease, multiple organ involvement, different subtypes and poorly understood etiology and pathogenesis. Yet, systemic immunosuppressive therapy is often the treatment of choice. Here we present a 60-year-old white female who developed skin thickening of her fingers extending to the forearms and of her proximal thighs after being treated with pembrolizumab for metastatic non-small cell lung cancer. It was difficult to determine internal organ involvement given her history of metastatic lung cancer, but scleroderma specific autoantibodies were negative. Her symptoms improved after treatment with methotrexate and stopping pembrolizumab. This is one of the first case reports of scleroderma secondary to pembrolizumab.