Page 43 - Sentinel lymph node biopsy in oral cavity cancer - Inne J. den Toom

nodes in the neck dissection specimen.34 Gurney et al. reported that the number and distribution of positive additional nodes in the neck, especially if outside the SLN basin, have an adverse impact on outcome.28 Groups based on tumour deposit had not been made but they suggest that the presence of a single positive SLNB does not imply a poor prognosis. This may potentially lead to more specified management plans for different prognostic groups as already implemented with a validated nomogram in 2 breast cancer.35 It may be that with SLNB tumour deposit can reliably be predicted, selecting the patients who truly benefit from an additional ND. Our preliminary data suggest that a wait-and-scan policy may be sufficient not only for patients with a negative SLNB, but also for patients with micrometastasis or ITC in the SLNB. However, to confirm this theory larger numbers of patients with longer follow-up are needed. DFS (92%) and OS (85%) using SLNB after negative USgFNAC in this study were comparable with our wait and scan (USgFNAC) strategy as previously reported (94% and 82%, respectively). OS seems to be better for patients undergoing a ND because of a positive SLNB as compared to patients undergoing a delayed ND in a wait and scan strategy (88% and 64%, respectively).17,35 Patients with nodal metastases had poorer outcome in overall survival analysis (Figure 1). Broglie et al. was the first who demonstrated worse outcome in patients with higher metastatic tumour load in SN, after stratification according to Hermanek et al.34,36 We also found lower overall survival rates in patients with higher metastatic tumour load in SNs (Figure 2). However, due to the low number of patients in some groups and the small number of events, statistical significance was not always reached. In the present study in floor of mouth tumours a lower identification rate and poorer accuracy as compared to other oral cavity subsites were found, although not statistically significant as in the studies of Ross et al. and Alkureishi et al.20,23 Despite the difficulty of pre- and peroperative localization and harvesting of SLNs in floor of mouth carcinomas due to the close proximity to the nodal basins and the primary tumour site, SLNB seems still reliable. In only 29% of the patients hotspots were identified in early lymphatic mapping probably due to slower lymphatic drainage in the floor of mouth. We believe that late lymphoscintigraphic imaging should be considered for these tumours to minimize the risk of false-negative results.37 The late visualisation of a hotspot on lymphoscintigraphy in floor of mouth tumours may also 41