Shoulder Metastasis: A Rare Nasopharyngeal Carcinoma Presentation.

BACKGROUND Nasopharyngeal carcinoma (NPC) is a rare malignant tumor that arises from the mucosal lining epithelium of the nasopharynx, most commonly at the lateral nasopharyngeal recess or fossa of Rosenmüller. According to global age-standardized incidence rates (ASIRs), in 2018 the incidence rate of nasopharyngeal carcinoma varied from 2.1 to 0.4 per 100 000 in Asia and Europe, respectively. The number of deaths exceeded 50 000. It is one of the few head and neck tumors prone to distant metastasis, most commonly to bones, lung, and liver. CASE REPORT In this case report, we present a rare case in which a 23-year-old male patient presented to our head and neck clinic. The patient presented initially to the orthopedic clinic with a right humeral mass lesion 10 cm with history of pain for the last 7 months. A Tru-Cut biopsy confirmed metastatic NPC. A nasopharyngeal biopsy further revealed his lesion to be an NPC undifferentiated type III. The patient was diagnosed with a T3 N2b M1 stage tumor and he was treated with chemoradiotherapy. CONCLUSIONS NPCs that present with a shoulder/humoral metastasis are very rare clinically. We are presenting this case to increase the awareness of the Otolaryngology - Head & Neck surgery, Orthopedic, and Oncology community of such a rare presentation.