Purpose: Data from literature show a mean incidence of occult metastases of 33% in early OCSCC. The gold standard for most authors is a selective neck dissection and a routine pathological examination. 60-70% of unnecessary neck dissections with associated morbidity, can be avoided by using SNB. The aim of this study is to present the results of one of the major Italian centres for the SNB procedure, reserving neck dissection only for proven positive lymphatic metastases.
Methods: From July 2004 to March 2015, 48 patients with transorally resectable cT1-T2N0 oral SCC were submitted to a lymphoscintigraphic examination one-three hours before surgery and a radio-guided SNB (same day protocol). Patients with a negative SNB were checked every 3 months by ultrasound examination. The minimum follow-up was 5 years.
Results: Sentinel nodes were found in all cases, with 71% localized in the ipsilateral neck only in levels I-II. Metastases were found in 15 out of 48 cases (31.2%), on levels I, II and III. Further metastatic nodes were found in 6 cases in the neck dissection specimen. In the cohort of 33 patients with SNB negative at 5 years, no-one had a recurrence on the ipsilateral neck.
Conclusion: This study confirms the accuracy of SNB in predicting the presence of occult metastases, sparing the need for unnecessary neck dissection in 70% of cases. The same day protocol is designed to detect sentinel nodes, which are almost always on neck level I-II, thereby limiting the number of nodes examined and the extension of the surgical approach.
Keywords: Lymphoscintigraphy; Neck dissection; Oral cavity squamous cell carcinoma (OCSCC); Radioguided biopsy; Sentinel node (SN); Sentinel node biopsy (SNB).