PRPF8 and metastatic neoplasm: As illustrated in Fig. 2, these five genes showed similar association profile between their increased expression and incidental diagnosis, reaching statistical significance for NOVA1, PRPF8 and SRSF9. In addition, NOVA1 expression levels were lower when positive malignancy was confirmed after fine needle aspiration, while SRSF9 expression was higher in metastatic disease.