Sentinel lymph node biopsy in N0 squamous cell carcinoma of the oral cavity and oropharynx.

OBJECTIVES To ascertain the feasibility of sentinel lymph node (SLN) localization by preoperative lymphoscintigraphy and intraoperative gamma probe radiolocalization and to determine the predictive value of the SLN for occult metastasis of the neck in N0 squamous cell carcinoma of the oral cavity and oropharynx. DESIGN A prospective study of 20 consecutive patients with N0 squamous cell carcinoma of the head and neck who underwent lymphoscintigraphy and SLN biopsy. INTERVENTIONS On the day before surgery, each patient who completed the study underwent a submucosal peritumoral injection of unfiltered technetium 99m sulfur colloid followed by lymphoscintigraphy. Focal areas of radioactivity were marked on the overlying skin. The following day, the patients underwent resection of the primary tumor, elevation of subplatysmal flaps, identification and removal of the SLNs as identified by gamma probe, and complete neck dissections. RESULTS Lymphoscintigraphy and gamma probe radiolocalization accurately identified 1 or more SLNs in all 20 patients. In 4 (20%) of the 20 patients, the SLN correctly identified metastatic disease. In no instance was the SLN negative when the lymphadenectomy specimen was positive. CONCLUSIONS In this study, the SLN had a negative predictive value of 100%. Sentinel lymph node biopsy is feasible and appears to accurately predict the presence of occult metastatic disease. Although further study is warranted, SLN biopsy could potentially guide head and neck oncologists to the patient with N0 disease who would benefit most from selective neck dissection and prevent the morbidity of unnecessary neck dissection.