Nonfunctioning giant pituitary adenomas: Invasiveness and recurrence

Abstract

Background:We report our surgical series of 35 patients with giant nonfunctioning pituitary adenomas (GNFPA). We analyzed the rule of Ki-67 antigen expression in predicting recurrence.Methods:Thirty-five patients were operated between 2000 and 2010. Suprassellar extension of the tumors were classified according to Hardy and Mohr based on magnetic resonance (MR) studies. Pituitary endocrine function and MR scans were assessed preoperatively and at 1, 6, and 12 months postoperatively. Immunohistochemical studies were based in regard to the expression of the proliferative Ki-67 index and the hormonal receptor for luteinizing hormone, follicle stimulating hormone, growth hormone, thyroid stimulating hormone, adrenocorticotropic hormone, and prolactin. Tumors specimens were obtained from 35 patients with GNFPA. Endoscopic transsphenoidal surgery was the approach of choice.Results:Thirty-five patients were submitted to 49 surgeries, 44 (89.8%) were transsphenoidal and 5 (10.2%) were transcranial. The most frequent preoperative complaints were visual acuity impairment and visual field defect in 25 (71.2%) and 23 (65.7%) cases, respectively. Improvement of visual acuitiy and visual field deficit after surgery was seen in 20 (80%) and 17 (73.9%) patients, respectively. Endocrinological deficits were encountered in 20 patients (57.1%). After surgery, 18 patients (51.4%) required hormonal replacement. Three patients had visual symptoms related to pituitary apoplexy and recovered after surgery. The Ki-67 labeling index (LI) ranged from <1% to 4.8%. The rate of recurrence in tumors with Ki-67 <3% was 7.7% (2 patients), Ki-67 >3% was present in 5 patients and the recurrence committed 3 patients.Conclusion:In our series, regardless the improvement of visual function and compressing symptoms, 5 patients with expression of Ki-67 LI more than 3% experienced a recurrence.

Markery Proliferacji I Inwazyjności W Guzach Przysadki Wydzielających Hormon Wzrostu

“…The role of Ki-67 as a marker of recurrence in pituitary tumours is not established. In small and non-homogenous patient groups with non-functioning PAs and somatotropinomas, expression of Ki-67 was not related to tumour recurrence nor to local invasion [23,24]. Magagna-Poveda et al [39] confirmed earlier studies that only the MIB-1 proliferation index was related to tumour recurrence.…”

“…The percentage of adenomas with positive immunostaining for Ki-67 in the study group was over 77% as compared to 88% or 100% as reported by other authors [23,24]. In our study somatotropinomas presented generally with Ki-67 index < 3%, and high variation (range …”

“…In a group of predominantly non-functioning adenomas, Ki-67 indices ranged from 1% to 4.8% [24] and from 1.4% to 5.2% in somatotropinomas [25]. TOPO 2A-positive immunostaining in our somatotropinomas was higher than that in patients with different types of PAs [11,13], where values of the TOPO 2A index ranged from 0% to 3.5%, with a median value of about 0.7% [13,26], against our median LI of 1.5%.…”

Surgical outcomes of the endoscopic endonasal transsphenoidal approach for large and giant pituitary adenomas: institutional experience with special attention to approach-related complications

“…during this time period. The primary objective was maximum decompression of the optic apparatus, the pituitary gland and surrounding brain structures 12 . Patients were positioned with their heads secured by a Mayfield head holder.…”

“…Traditionally, these tumors have been handled by the transcranial route, alone or in combination with the transsphenoidal resection 7,9,11,12 . Some recent reports have described the usefulness of the endoscopic endonasal route in the their management, even though its safety and effectiveness of treating large and giant pituitary adenomas is yet to be established in the literature 6,8,10,11,13,14,15,16 .…”