Metastatic cancer to the floor of mouth: The lingual lymph nodes

Background. The upper level of a cervical lymphadenectomy is anatomically defined at its anterior extent by the lower border of the mandible and, in surgical practice, by the lingual nerve. A neck dissection completed below this level is generally considered adequate for removal of lymph nodes at risk for metastases from oral cavity cancer. Traditional discontinuous neck dissections do not provide for removal of floor of mouth tissue along with the primary and neck specimens. Methods. A case report presenting biopsies from a T2N2bM0 squamous cell carcinoma of the mobile tongue and adjacent floor of the mouth in a 73-year-old man. Results. Deep biopsy of a ventral tongue and floor of mouth squamous cell carcinoma revealed occult metastatic cancer to lymph nodes located in the superficial floor of mouth associated with the sublingual gland above the lingual nerve. This report identifies floor of mouth lymph nodes that can be involved with cancer and missed through the standard practice of discontinuous neck dissection. Conclusions. This finding offers evidence that, in certain cases, a traditional discontinuous neck dissection may not address all lymph nodes at risk in the treatment of oral cavity cancer. Further investigation into lymph node distribution within the oral cavity is warranted to reappraise the upper limits of cervical lymphadenectomy. (C) 2002 Wiley Periodicals, Inc.