Number and location of radiolabeled, intraoperatively identified sentinel nodes in 48 head and neck cancer patients with clinically staged N0 and N1 neck.

The value of sentinel node (SN) biopsy for squamous cell carcinoma of the head and neck (HNSCC) has not been determined yet. A critical evaluation of this concept seems to be mandatory with regard to the increasing acceptance of SN biopsy in other tumor entities. Against the background of the results of 48 previously untreated patients, a reproducible technique for SN biopsy in the head and neck level, which has been adjusted to the special topographic conditions of this anatomic region, is presented. Methods included intraoperative SN biopsy, which was performed in 48 previously untreated patients suffering from squamous cell carcinoma (2x lower lip, 8x oral cavity, 20x oropharynx, 15x larynx, 3x hypopharynx). Using ultrasound imaging, 43 patients were staged as N0 necks, and 5 patients were staged as N1 necks. Fine-needle aspiration cytology (FNAC) was performed in cases of doubt. Surgery on the neck was carried out according to the suspected stage of lymphogenic spread once the SN1 as well as one or two further hot nodes (SN2, SN3) had been identified. Numbers and distribution of the intraoperatively excised nodes SN1-3 were documented according to their relation to the tumor location. Post-operatively, the histologic results of the intraoperatively excised nodes SN1-3 were compared to the histologies of the neck dissection specimen. Results showed that in all 48 patients, a SN1 could be identified intraoperatively. In 20 cases an additional SN2 and in 6 cases a SN3 was diagnosed. In carcinomas of the lower lip and oral cavity, the SN1 was found in 4 cases in level I (2x lower lip, 2x floor of the mouth) and in 6 cases in level II (6x lateral tongue). In carcinomas of the oropharynx, the respective nodes were found in 17 of 20 cases in level II (carcinomas of the tonsil) and in 3 cases in level III (carcinomas of the base of the tongue). In supraglottic carcinomas the SN1 was identified in 8 of 10 cases in level II and in 2/5 patients with glottic carcinomas, while in 3/5 glottic carcinomas as well as in all hypopharyngeal carcinomas, the SN1 was found in level III. In relation to the predictiveness of the detected SN, it has to be remarked that in 38 patients a SN1 free of tumor was representative for the regional lymph node status (pN0). An isolated metastasis (pN1) was diagnosed in the SN (9x SN1, 1x SN2) in 10 patients. In conclusion, the results of a SN biopsy modified to a strictly intraoperative method of detection are encouraging. Critical indications showed that a thorough and standardized technical performance of the injection as well as a mandatory, so far unchanged, neck dissection form the basis for the development of a SN concept for SCCs of the upper aerodigestive tract. The value of the SN concept, however, currently remains unclear for patients suffering from HNSCC.