In the Journal of Clinical Periodontology vol. 36, issue 6, of June 2009: 488-492, an original paper was published called: �Metastatic tumours to the oral cavity: a survival study with a special focus on gingival metastasis� by Seoane J, Van der Waal RIF, Cameselle-Teijeiro J, Anton I, Tardio A, Alcazar Otero JJ, Varela Centelles P, Diz P, a team that includes authors from several prestigious higher education institutions located in Spain and Holland.