Poliosis Is Associated with Response to Checkpoint-Inhibitor Therapy: A Case Report of Two Patients with Multifocal Metastatic Melanoma

The advent of immune-checkpoint inhibitors (ICIs) led to significant improvements in the treatment of patients with advanced melanoma and resulted in durable tumor responses in a considerable number of advanced melanoma patients. Next to the immune-mediated anti-neoplastic effects, ICIs may cause various immune-related adverse events (irAEs), often requiring early discontinuation of therapy. By contrast, cutaneous irAE rarely enforce treatment discontinuation but may represent simple and robust predictive markers for treatment response. The relevance of irAEs as clinical markers for an improved response to immunotherapy is still debated. We report here on two patients with multifocal metastatic melanoma who developed the rare event of generalized poliosis during combined immunotherapy with ipilimumab plus nivolumab, followed by a near-complete and durable response. Our observations suggest that poliosis may be a useful and simple clinical indicator of anti-tumor immunity, clinical response and favorable survival outcome in advanced melanoma patients treated with ICI.