Case Series: Merkel Cell Carcinoma of The Head And Neck in The Oral and Maxillofacial Department in University Hospital Limerick with A Literature Review

Introduction
Merkel cell carcinoma (MCC) is a rare, aggressive neuroendocrine skin cancer with increasing incidence and high mortality. Early recognition and management are essential. We present a series of MCC cases managed within the Oral and Maxillofacial Surgery Department at University Hospitals Limerick (UHL). These cases highlight MMC’s aggressive nature, treatment options, and prognosis.

Case Reports
Case 1: A 74-year-old man diagnosed with right cheek MCC with metastatic to the parotid gland. He underwent right superficial parotidectomy followed by chemo-radiotherapy.

Case 2: An 80-year-old man had a right temple MCC. PET imaging demonstrated metastasis to parotid. He was treated with superficial parotidectomy and neck dissection, but declined radiotherapy.

Case 3: A 69-year-old man with an left nasal ala MCC, underwent excision with local flap reconstruction. PET ruled out metastasis of the disease and he received adjuvant radiotherapy to the primary site.

Case 4: An 80-year-old man had an nasal bridge MCC. PET showed no metastasis, and he received adjuvant radiotherapy to the primary site only.

Discussion
MCC is an uncommon but highly aggressive cutaneous malignancy, most often arising on the head and neck. Risk factors include immunosuppression, with solid organ recipients carrying a 24-fold increased risk. Surgery is the mainstay of treatment, usually followed by adjuvant radiotherapy. Chemotherapy is reserved for advanced disease, while immunotherapy is an emerging and promising option.

Conclusion
MCC is rarely suspected clinically but is rapidly becoming more common. Imaging, particularly PET, should be considered where clinically indicated. Management typically involves surgery with adjuvant radiotherapy; chemotherapy and immunotherapy may be considered in metastatic or recurrent disease. Further studies surrounding knowledge of disease progression and management, should be carried out