Complete reversibility of pembrolizumab-induced eosinophilic fasciitis without corticosteroids: A case report

Checkpoint inhibitor immunotherapy has recently started to play a fundamental role in the management of metastatic melanoma. It is however accountable for many undesirable adverse effects involving many organ systems. Eosinophilic fasciitis is a rare immune-related adverse effect associated to checkpoint inhibitors such as pembrolizumab and nivolumab. We report the case of a 25-year-old male who received pembrolizumab as a second-line therapy for metastatic melanoma. Approximately 8 months after starting the treatment, the patient developed signs and symptoms of eosinophilic fasciitis, including edema of his hands and lower legs, as well as joint limitation. Pembrolizumab was discontinued after 15 cycles because of symptom progression. The patient experienced complete resolution of symptoms 4 months after cessation of pembrolizumab and without corticosteroids. This case illustrates the reversibility of this immune adverse effect by discontinuation of the treatment, speculating that corticotherapy may not be needed in all cases.