Oropharyngeal metastasis of merkel cell carcinoma: Case report and review of the literature

Abstract

Merkel cell carcinoma (MCC) is an aggressive neuroendocrine tumor of the skin, most commonly affecting sun exposed areas of the head and neck in older patients. Surgery remains the mainstay of treatment followed by adjuvant radiation or chemoradiation therapy in appropriately selected patients. Though MCC is associated with high rates of locoregional recurrence and propensity for distant metastases, metastatic disease involving the oropharynx is exceedingly rare; the optimal therapeutic approach in this setting remains controversial. Herein, we report a rare case of metastatic MCC to the base of tongue presenting as acute oropharyngeal hemorrhage in an 86-year-old male without an identifiable primary lesion. Definitive airway management and treatment with tumor-directed radiation and concurrent pembrolizumab were successful in this case. Optimal diagnostic and treatment strategies are discussed in addition to a review of the literature for patients with metastatic MCC affecting the oropharynx. Further, the role of transoral robotic surgery (TORS), systemic chemotherapeutic regimens, and immunotherapy in this setting are highlighted.