Letter to the editor: "Is preoperative ultrasonography accurate in measuring tumor thickness and predicting the incidence of cervical metastasis in oral cancer?". - Lodder WL; Hauptmann M; Teertstra HJ; van den Brekel MW; Balm AJ; Lodder, W L; Hauptmann, M; Teertstra, H J; van den Brekel, M W M; Balm, A J M (Oral Oncology, 2010)