Lymphoscintigraphic detection and fine needle aspiration of sentinel nodes in head and neck cancer patients

Objective : Investigation of the possibility to improve staging of head and neck cancer patients without palpable metastases (NO neck) by using a combination of lymphoscintigraphy and fine needle aspiration cytology of sentinel lymph nodes. Methods : Twenty-four patients with a squamous cell carcinoma of the oral cavity or oropharynx and a clinically NO neck as well as one patient with a N1 neck received 2-4 peritumoral injections with 15-60 MBq ^99mTc colloidal albumin, directly followed by dynamic lymphoscintigraphy. After visualization of the sentinel node(s) (SN) a handheld gammaprobe was used to mark its localization on the skin. Subsequent ultrasound guided fine needle aspiration (USgFNA) was performed of the SN as well as other suspected lymph nodes. The aspirate residue was counted for radio-activity to confirm the aspiration of the true SN. Nine patients underwent an elective neck dissection. The other patients underwent transoral excision and regular USgFNA cytology of the neck during follow-up. Results : In 22 out of 25 patients 1-2 SNs were visible, 1 patients showed 4 SNs. Confirmation of the aspirated SN was possible. USgFNAC was possible in 22 out of 23 patients, one SN was considered too small for aspiration. In 18 patients the SN was cytologically negative. One patient had a false negative SN. In 4 patients the SN revealed tumor positive. In case of a neck dissection the SN correctly reflected the lymph node status of the neck. Conclusion : Lymphoscintigraphic detection and USgFNA of the SN is a workable technique and is feasible in patients with a clinically negative neck. Currently the sensitivity of this technique, combined with molecular assessment of the aspirate, using E48 RT-PCR is assessed in a large group of patients.