Pituitary tumour transforming gene (PTTG) expression correlates with the proliferative activity and recurrence status of pituitary adenomas: a clinical and immunohistochemical study

Abstract

PTTG is expressed in approximately 90% of pituitary tumours of different histotypes but with a high variability from one case to another. As expected, PTTG expression parallels that of Ki-67 and both are correlated to a more aggressive behaviour. However, a 2.9% Ki-67 cut-off proved to be the most reliable biological marker for predicting the recurrence potential of these tumours, when an adequate postsurgical follow-up is considered.