Koos Boeve

93 Lymphatic drainage patterns of oral maxillary tumors Sentinel lymph node locations All SLNBs were performed without complications and all cervical located sentinel lymph nodes were intra-operatively identified and removed. In 10 patients, the sentinel lymph nodes were visible on lymphoscintigraphy at cervical level I, II or III. In Figure 1, the locations are given of these cervical sentinel lymph nodes on lymphoscintigraphy at the side planned for SLNB. Only in 2 patients a parapharyngeal sentinel lymph nodes was visible in addition to other sentinel lymph nodes at cervical level II (Figure 2). In patient #2, the sentinel lymph node was located retromaxillary at the ipsilateral side, and in patient #7 the sentinel lymph node was located retropharyngeally at the contralateral side. In the other 9 patients no parapharyngeal sentinel lymph node was detected (Table 2). During surgery, 19 lymph nodes with a high radioactive signal on the γ-probe were harvested at the marked positions on the skin (Table 2). In patients 1, 3, 6, 7 and 9, additional non-radioactive harvested lymph nodes were separated from the SLNs using the γ-probe. The SLNB was performed bilaterally in 2 patients. Two patients had a SLNB at the ipsilateral side and in 6 patients, the SLNB was performed at the contralateral side in the neck compared to the tumor side (Table 2). In patient #11, no sentinel lymph node was visible at the lymphoscintigraphy after injection of 100 MBq 99m Tc-nanocolloid. The tumors ranged in pathological T classification fromT1 to T4. Figure 1. Positions of sentinel lymph nodes (SLNs) on the lymphoscintigraphy separated for the ipsilateral and contralateral sides compared to the tumor. Numbers in the red stars correspond with the patients in the tables and each star is one hot spot on the lymphoscintigraphy. More contralateral SLNs were imaged because only the SLNs on the side that was planned for the sentinel lymph node biopsy are shown (see also Table 2). Patient #11 had no detectable SLNs at the lymphoscintigraphy.