Impact of age on postsurgical outcomes of nonfunctioning pituitary adenomas.

PURPOSE: The management of pituitary adenomas in the elderly has become a relevant clinical issue, in relationship with improved life expectancy and spreading use of imaging techniques. In this single-center and retrospective study, we investigated the impact of age on peri- and postsurgical outcomes in patients undergoing transnasal sphenoidal (TNS) surgery for pituitary adenomas. METHODS: One-hundred-sixty-nine patients (62% males) undergoing endoscopic transphenoidal (TNS) surgery for nonfunctioning pituitary adenomas (NFPAs) were enrolled. Patients were subdivided into three groups according to age tertiles: ≤56 (group 1), 57-69 (group 2), and ≥70 (group 3) years. Postsurgical and endocrinological outcomes were evaluated and compared among the three age groups. RESULTS: 37/169 patients (21.9%) developed at least one perisurgical complication, without significant association with the patients' age (P = 0.838), Charlson co-morbidity score (P = 0.326), and American Society of Anesthesiologist score (P = 0.616). In the multivariate regression analysis, the adenoma size resulted the only determinant of perisurgical complication (odds ratio [OR] 1.07, 95% confidence interval [C.I.] 1.00-1.13; P = 0.044). The development and the recovery of at least one pituitary hormone deficiency were observed in 12.2% and 14.2% of patients, respectively. The risk of developing new pituitary hormone deficiencies was correlated with cavernous sinus invasion as evaluated by magnetic resonance imaging (hazard ratio [HR] 4.19, 95% C.I. 1.39-12.66; P = 0.010), whereas the probability to normalize at least one pituitary hormone deficiency was significantly correlated with younger age of patients (HR 0.27, 95% CI 0.12-0.61; P = 0.002). CONCLUSIONS: The results of this study reinforce the concept that endoscopic TNS surgery is a safe therapeutic option in the elderly patients with NFPA, even in presence of comorbidities and high anesthetic risk.

Filamin A (FLNA) plays an essential role in somatostatin receptor 2 (SST2) signaling and stabilization after agonist stimulation in human and rat somatotroph tumor cells.

Somatostatin receptor type 2 (SST2) is the main pharmacological target of medical therapy for GH-secreting pituitary tumors, but molecular mechanisms regulating its expression and signaling are largely unknown. The aim of this study was to investigate the role of cytoskeleton protein filamin A (FLNA) in SST2 expression and signaling in somatotroph tumor cells. We found a highly variable expression of FLNA in human GH-secreting tumors, without a correlation with SST2 levels. FLNA silencing in human tumoral cells did not affect SST2 expression and localization but abolished the SST2-induced reduction of cyclin D1 (-37% ± 15% in control cells, P < .05 vs basal) and caspase-3/7 activation (+63% ± 31% in control cells, P < .05 vs basal). Overexpression of a FLNA dominant-negative mutant that specifically prevents SST2-FLNA binding reduced SST2 expression after prolonged agonist exposure (-55% ± 5%, P < .01 vs untreated cells) in GH3 cells. Moreover, SST2-induced apoptotic effect (77% ± 54% increase of caspase activity, P < .05 vs basal) and SST2-mediated ERK1/2 inhibition (48% ± 17% reduction of ERK1/2 phosphorylation, P < .01 vs basal) were abrogated in cells overexpressing another FLNA mutant that prevents FLNA interaction with partner proteins but not with SST2, suggesting a scaffold function of FLNA in somatotrophs. In conclusion, these data demonstrate that FLNA is involved in SST2 stabilization and signaling in tumoral somatotrophs, playing both a structural and functional role.

Cyclic adenosine 3'-5'-monophosphate (cAMP) exerts proliferative and anti-proliferative effects in pituitary cells of different types by activating both cAMP-dependent protein kinase A (PKA) and exchange proteins directly activated by cAMP (Epac).

In the pituitary the activation of cyclic adenosine 3'-5'-monophosphate (cAMP) dependent pathways generates proliferative signals in somatotrophs, whereas in pituitary cells of other lineages its effect remains uncertain. Moreover, the specific role of the two main cAMP effectors, protein kinase A (PKA) and exchange proteins directly activated by cAMP (Epac), has not been defined. Aim of this study was to investigate the effect of cAMP on pituitary adenomatous cells proliferation and to identify PKA and Epac differential involvement. We found that cAMP increased DNA synthesis and cyclin D1 expression in somatotropinomas, whereas it reduced both parameters in prolactinomas and nonfunctioning adenomas, these effects being replicated in corresponding cell lines. Moreover, the divergent cAMP effects were mimicked by Epac and PKA analogs, which activated Rap1 and CREB, respectively. In conclusion, we demonstrated that cAMP exerted opposite effects on different pituitary cell types proliferation, these effects being mediated by both Epac and PKA.

Transnasal 3D endoscopic skull base surgery: questionnaire-based analysis of the learning curve in 52 procedures.

In the past decade, surgical treatment of skull base pathologies has greatly advanced through the advent of the endoscope and later of the high definition endoscope. Recently a new type of three dimensional (3D) scope has been introduced to permit the surgeon a real stereoscopic vision of the operating field and to overcome the limitations of the 2D endoscopic set up. As with all new technologies a formalized adaptation period is essential for the surgeon to secure steady outcomes and low complications. To determine the subjective difficulties that one may encounter during this sensitive period we therefore devised and analyzed a questionnaire that evaluated the first ten procedures with the 3D device of junior and senior ENT and neurosurgeons. 52 consecutive patients were treated with purely 3D transnasal endoscopy for skull base pathologies. Sensation of strain or dizziness, difficulties in anatomical orientation and difficulties in performing the surgical gesture were assessed for each surgeon. The learning curve and difficulties of junior and senior surgeons are discussed and strategies to overcome the initial problems are devised. Our results confirm that after only few procedures, the advantages of the 3D endoscopic system including better visualization and depth perception are able to outweigh the inconveniences that go hand in hand with the learning of a new skill set.