頸部腫塊是門診病患相當常見的症狀，其發生可能是由於感染、癌症或其他原因。作診斷與處置時亦須將 頸部之各個構造，諸如淋巴結、甲狀腺、唾液腺一併考慮。本文章報告老年病患，其左頸部有一許久未消之腫 塊，經理學檢查、放射檢查、核醫檢查、切片檢查及正子造影檢查後，診斷為惡性腫瘤之頸部淋巴轉移，惟原 發腫瘤來源不明。由於口內並未發現可疑病灶，鼻咽癌為其中可能診斷，但鼻咽內視鏡、鼻咽切片檢查及血 清病毒檢查皆無法證實，故僅能維持此原發部位不明之惡性腫瘤合併頸部及遠端轉移之診斷。(J. Family Dent. 9(4): 24-29, 2015)

Neck mass is a common head and neck problem observed in patients visiting local clinics, and it can be caused by bacterial or viral infections, cancer, or other causes. Structures within the neck include the lymph nodes, thyroid gland, parathyroid glands, and salivary glands. We present a case report of a patient who had a left neck mass for several months. The patient was diagnosed with a metastatic malignant tumor after a physical examination, imaging examination, endoscopic examination, fine needle aspiration biopsy, and direct biopsy of the mass; however, the primary tumor site was uncertain. Although nasopharyngeal carcinoma was highly suspected during the imaging examination, the endoscopic examination did not confirm the diagnosis. An Epstein-Barr virus serological examination also revealed negative results; therefore, the primary lesion site remained unknown. (J. Family Dent. 9(4): 24-29, 2015)