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Although most pituitary neuroendocrine tumors (PitNETs)/pituitary adenomas remain intrasellar, a significant proportion of tumors show parasellar invasive growth and 6% to 8% infiltrate the bone structures, thus affecting the prognosis. There is an unmet need to identify novel markers that can predict the parasellar growth of PitNETs. Furthermore, mechanisms that regulate bone invasiveness of PitNETs and factors related to tumor vascularization are largely unknown. We used genome-wide mRNA analysis in a cohort of 77 patients with PitNETs of different types to explore the differences in gene expression patterns between invasive and noninvasive tumors with respect to the parasellar growth and regarding the rare phenomenon of bone invasiveness. Additionally, we studied the genes correlated to the contrast enhancement quotient, a novel radiological parameter of tumor vascularization. Most of the genes differentially expressed related to the parasellar growth were genes involved in tumor invasiveness. Differentially expressed genes associated with bone invasiveness are involved in NF-κB pathway and antitumoral immune response. Lack of clear clustering regarding the parasellar and bone invasiveness may be explained by the influence of the cell lineage-related genes in this heterogeneous cohort of PitNETs. Our transcriptomics analysis revealed differences in the molecular fingerprints between invasive, including bone invasive, and noninvasive PitNETs, although without clear clustering. The contrast enhancement quotient emerged as a radiological parameter of tumor vascularization, correlating with several angiogenesis-related genes. Several of the top genes related to the PitNET invasiveness and vascularization have potential prognostic and therapeutic application requiring further research. [ABSTRACT FROM AUTHOR]

Objective: Data on pre- and postoperative pituitary function in nonfunctioning pituitary adenomas (NFPA) are not consistent. We aimed to investigate pituitary function before and up to 5 years after transsphenoidal surgery with emphasis on the hypothalamic-pituitary-adrenal axis (HPA). Design and methods: Data from the Swedish Pituitary Register was used to analyze anterior pituitary function in 838 patients with NFPA diagnosed between 1991 and 2014. Patients who were reoperated or had received radiotherapy were excluded. Results: Preoperative ACTH, TSH, LH/FSH, and GH deficiencies were reported in 31% (236/755), 39% (300/769), 51% (378/742), and 28% (170/604) of the patients, respectively. Preoperative median tumor volume was 5.0 (2.4-9.0) cm³. Among patients with preoperative, 1 year and 5 years postoperative data on the HPA axis (n = 428), 125 (29%) were ACTH-deficient preoperatively. One year postoperatively, 26% (32/125) of them had recovered ACTH function while 23% (70/303) patients had developed new ACTH deficiency. Thus, 1 year postoperatively, 163 (38%) patients were ACTH-deficient (P < .001 vs. preoperatively). No further increase was seen 5 years postoperatively (36%, P = .096). At 1 year postoperatively, recoveries in the TSH and LH/FSH axes were reported in 14% (33/241) and 15% (46/310), respectively, and new deficiencies in 22% (88/403) and 29% (83/288), respectively. Conclusions: Adrenocorticotrophic hormone deficiency increased significantly at 1 year postoperatively. Even though not significant, some patients recovered from or developed new deficiency between 1 and 5 years postoperatively. This pattern was seen in all axes. Our study emphasizes that continuous individual evaluations are needed during longer follow-up of patients operated for NFPA. [ABSTRACT FROM AUTHOR]

Context: Aggressive pituitary tumors (APTs) are characterized by unusually rapid growth and lack of response to standard treatment. About 1% to 2% develop metastases being classified as pituitary carcinomas (PCs). For unknown reasons, the corticotroph tumors are overrepresented among APTs and PCs. Mutations in the alpha thalassemia/mental retardation syndrome X-linked (ATRX) gene, regulating chromatin remodeling and telomere maintenance, have been implicated in the development of several cancer types, including neuroendocrine tumors.Objective: To study ATRX protein expression and mutational status of the ATRX gene in APTs and PCs.Design: We investigated ATRX protein expression by using immunohistochemistry in 30 APTs and 18 PCs, mostly of Pit-1 and T-Pit cell lineage. In tumors lacking ATRX immunolabeling, mutational status of the ATRX gene was explored.Results: Nine of the 48 tumors (19%) demonstrated lack of ATRX immunolabelling with a higher proportion in patients with PCs (5/18; 28%) than in those with APTs (4/30;13%). Lack of ATRX was most common in the corticotroph tumors, 7/22 (32%), versus tumors of the Pit-1 lineage, 2/24 (8%). Loss-of-function ATRX mutations were found in all 9 ATRX immunonegative cases: nonsense mutations (n = 4), frameshift deletions (n = 4), and large deletions affecting 22-28 of the 36 exons (n = 3). More than 1 ATRX gene defect was identified in 2 PCs.Conclusion: ATRX mutations occur in a subset of APTs and are more common in corticotroph tumors. The findings provide a rationale for performing ATRX immunohistochemistry to identify patients at risk of developing aggressive and potentially metastatic pituitary tumors. [ABSTRACT FROM AUTHOR]