Koos Boeve

90 Chapter 5 MATERIAL AND METHODS Patient selection All consecutive patients diagnosed with oral maxillary cancer at the Department of Oral & Maxillofacial Surgery of the University Medical Center Groningen between December 01, 2012 and April 22, 2016, were included in the analysis if they had a primary oral tumor located at the hard palate or alveolar bone. Patient characteristics are given in Table 1. Information regarding patient characteristics, clinical and pathological tumor characteristics and diagnostic imaging data was collected retrospectively. All patients were treated according to the Dutch National guidelines for oral cavity cancer [21]. Because SLNB is part of this guideline, no approval was required from the hospital research ethics board according to the Dutch ethical regulations [22]. Table 1. Patient and tumor characteristics Patient # Sex Age at treatment Tumor morphology Location Tumor cTN pTN 1 Female 75 OSCC Upper gum right side T1N0 T2N2b 2 Female 64 OSCC Upper gum left side T1N0 T1N0 3 Female 90 OSCC Upper gum right side T4aN0 T4aN0 4 Female 73 OSCC Hard palate right side, close to midline T4aN0 T4aN0 5 Female 60 OSCC Upper gum left side, close to midline T4N2b/c T4N0 6 Male 77 OSCC Upper gum left side, close to midline T4N0 T4N0 7 Female 54 Melanoma Hard palate right side, close to midline T4N1 T4N2b 8 Male 70 OSCC Upper gum left side, close to midline T4aN0 T4aN2b 9 Female 88 OSCC Hard palate left side, close to midline T2N0 T2N0 10 Female 65 OSCC Upper gum, midline and right side T1N0 T2N0 11 Male 66 OSCC Upper gum right side T4N0 T2Nx* Abbreviations: cTN; clinical TN classification, pTN; pathological TN classification, OSCC; oral squamous cell carcinoma. * Patient #11 had no detectable SLNs at the lymphoscintigraphy