PTTG overexpression in non-functioning pituitary adenomas: Correlation with invasiveness, female gender and younger age

Abstract Background Non-functioning pituitary adenomas (NFPA) are prevalent pituitary neoplasms. Because they do not present with hormonal hypersecretion, there is no marker that indicates regrowth or recurrence, as in other adenomas. Objectives Evaluate the immunohistochemical expression of PTTG, CD105 and Ki-67 and their relationships with age, gender, invasiveness, hormonal expression and regrowth or recurrence in the follow-up of NFPA operated and not submitted to radiotherapy. Methods Included 56 patients submitted to transsphenoidal surgery. Clinical data were obtained from medical records. The invasion degree was obtained by Hardy's classification. Results Mean age 55 ± 13.6 years, 62.5% men and 68% invasive. Lesion persistence was present in 62.2% and regrowth in 35.7%. The recurrence-free survival rate was 94.5%, 75.4% and 69.1% (1, 2 and 3 years). No patient presented recurrence. The PTTG was positive in 55.3%, with statistically significant relationship with invasiveness, age and female gender, without relation to regrowth. The microvascular density showed statistically significant relationship with male gender, negative correlation with PTTG ( r  = −0.434, p  = 0.001), and no relation with invasiveness and regrowth. The Ki-67 showed statistically significant relationship with age, tendency towards regrowth ( p  = 0.054) and, with no relation to invasiveness. Conclusions It is suggested that PTTG can be used as a prognostic marker in NFPA.