Carcinoma of unknown primary origin (CUP) refers to metastatic neck lymphadenopathy without identification of the primary tumor lesion within five years. The primary tumor may have spontaneously regressed, been destroyed by the immune system, or progressed rapidly. CUP accounts for 2-3% of head and neck malignancies. Metastases most commonly occur in levels II and III of the neck and are usually squamous cell carcinoma. The five-year survival rate exceeds 50% regardless of management. Diagnosis involves clinical examination, imaging like CT/PET scans, and panendoscopy with biopsies of potential sites like the tonsils, base of tongue, and nasopharynx, which can identify the primary in over