Using immunohistochemical labelling, 100% of the included patients were positive for Cytokeratin 7, 87.1% for Neuron Specific Enolase, 64.5% for Synaptrophysin, 58.1% for Chromogranin, 48.4% for Carcinoembryonic Antigen, 41.9% for Thyroid Transcription Factor-1.