The immunohistochemistry (IHC) analyses showed that tumor cells were positive for thyroid transcription factor-1 (TTF-1) and neuroendocrine markers, including chromogranin A (Figure 2B), synaptophysin (Figure 2C), INSM1 (insulinoma-associated protein 1), and CD56 (Figure 2D). This evidence concerns the gene NKX2-1 and neoplasm.