Merkel CellsCarcinoma, Merkel CellMerkel cell polyomavirusPolyomavirus InfectionsSkin NeoplasmsPolyomavirusKeratin-20Tumor Virus InfectionsVibrissaeAntigens, Viral, TumorMechanoreceptorsLingual FrenumSkinFacial NeoplasmsDNA NucleotidylexotransferaseAntigens, Polyomavirus TransformingQuinacrineNerve EndingsApudomaEnkephalin, MethionineDNA, ViralKeratin-8TouchHair FollicleNeuroendocrine Secretory Protein 7B2Blood Buffy CoatSynaptophysinImmunohistochemistry