关键词: 口底癌, 解剖, 侵袭, 淋巴结转移

Abstract: The invasion and metastasis of carcinoma of the floor of mouth（FMC） are closely related to its anatomical features. The floor of the mouth is located in the sublingual area，which is characterized by thin submucosa，multi-directional lymphatic flow and rich neurovascular innervation. The ducts of sublingual and submandibular glands directly open to the oral mucosa and keeps close anatomical relationship with surrounding tissues，organs and the multiple spaces in the maxillofacial region. The cancer of the floor of mouth has a high degree of malignancy， and surrounding organs invasion，peritoneal dissemination and lymphatic metastasis may occur in early FMC. Grasping the invasion and metastasis properties of FMC carcinoma from the perspective of anatomy will help to understand its clinical manifestations at different stage，to make proper treatment and to assess the prognosis of FMC.

Key words: carcinoma of the floor of mouth, anatomy, invasion, lymph node metastasis