Complete Tumor Response of Tracheal Squamous Cell Carcinoma After Treatment With Pembrolizumab.

Persistent carcinoma of the trachea is an uncommon thoracic malignancy with limited treatment options. To our knowledge pembrolizumab, an immunotherapy targeting programmed death 1, has not been previously reported as an effective therapy for tracheal carcinoma. Here we describe a case of recurrent tracheal squamous cell carcinoma refractory to photodynamic therapy, radiotherapy, and cryotherapy. Programmed death ligand 1 was positive in 90% to 95% of tumor cells. A complete tumor response was observed after three months of treatment with pembrolizumab. No adverse events were reported at the 11-month follow-up. Based on our experience, pembrolizumab represents another viable treatment option for tracheal carcinoma.