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Michael Buchfelder - One of the best experts on this subject based on the ideXlab platform.
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intraoperative high field mri for transsphenoidal reoperations of Nonfunctioning Pituitary Adenoma
Journal of Neurosurgery, 2014Co-Authors: Sven Berkmann, Christopher Nimsky, Rudolf Fahlbusch, Sven Schlaffer, Michael BuchfelderAbstract:Object The loss of anatomical landmarks, frequently invasive tumor growth, and tissue changes make transsphenoidal reoperation of Nonfunctioning Pituitary Adenomas (NFAs) challenging. The use of intraoperative MRI (iMRI) may lead to improved results. The goal of this retrospective study was to evaluate the impact of iMRI on transsphenoidal reoperations for NFA. Methods Between September 2002 and July 2012, 109 patients underwent reoperations in which 111 transsphenoidal procedures were performed and are represented in this study. A 1.5-T Magnetom Sonata Maestro Class scanner (Siemens) was used for iMRI. Follow-up iMRI scans were acquired if gross-total resection (GTR) was suspected or if no further removal seemed possible. Results Surgery was performed for tumor persistence and regrowth in 26 (23%) and 85 (77%) patients, respectively. On the initial iMRI scans, GTR was confirmed in 19 (17%) patients. Remnants were located as follows: 65 in the cavernous sinus (71%), 35 in the suprasellar space (38%), 9 in...
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follow up and long term outcome of Nonfunctioning Pituitary Adenoma operated by transsphenoidal surgery with intraoperative high field magnetic resonance imaging
Acta Neurochirurgica, 2014Co-Authors: Sven Berkmann, Christopher Nimsky, Rudolf Fahlbusch, Sven Schlaffer, Michael BuchfelderAbstract:Background Intraoperative MRI (iMRI) increases gross total resection (GTR) rates in transsphenoidal surgery; however, long-term follow-up data is lacking. The objective is to assess the outcome of patients with Nonfunctioning Pituitary Adenomas (NFA) at a mean follow-up of > 5 years.
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follow up and long term outcome of Nonfunctioning Pituitary Adenoma operated by transsphenoidal surgery with intraoperative high field magnetic resonance imaging
Acta Neurochirurgica, 2014Co-Authors: Sven Berkmann, Christopher Nimsky, Rudolf Fahlbusch, Sven Schlaffer, Michael BuchfelderAbstract:Intraoperative MRI (iMRI) increases gross total resection (GTR) rates in transsphenoidal surgery; however, long-term follow-up data is lacking. The objective is to assess the outcome of patients with Nonfunctioning Pituitary Adenomas (NFA) at a mean follow-up of > 5 years. Patients with NFA operated in a single institution with resection control by a 1.5 T intraoperative magnetic resonance imaging (iMRI) scanner and no previous Pituitary surgery were included. Microscopical transsphenoidal approaches with optional endoscopy were used. The iMRI was chosen for spacious suprasellar or retrosellar and/or invasive tumours. IMRI-scans were made if GTR or if nonresectable remnants were presumed. The patients had a full neuroradiological, endocrinological and ophthalmological follow-up at the institution. Eighty-five patients (67 % male;55 ± 14 years) with a follow-up of 5.6 ± 1.9 years were included. The initial GTR rate on iMRI was 44 %. In 83 %, further resections were possible, resulting in a final GTR rate of 66 %. In invasive tumours, the GTR rate was increased by 29 %. The detection of remnants by iMRI had high sensitivity and specificity (100 %), as opposed to endoscopy (21 %;78 %). During follow-up, four (7 %) tumours recurred and 14 (64 %) remnants grew. The recurrence and regrowth rate were 0.013 and 0.114 patients/years, respectively. Seventy-nine percent of the growing remnants were seen < 5 years postoperatively. The use of iMRI for transsphenoidal resection leads to low recurrence rates. Even in case of invasive tumours, distinctly more patients show long tumour-free follow-ups. Tumour remnants detected by iMRI are at high risk to grow within 5 years after surgery.
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tumor shrinkage after transsphenoidal surgery for Nonfunctioning Pituitary Adenoma
Journal of Neurosurgery, 2013Co-Authors: Sven Berkmann, Sven Schlaffer, Michael BuchfelderAbstract:Object Volume reduction of Nonfunctioning Pituitary Adenomas has been described, for example, after radiotherapy and Pituitary tumor apoplexy. Even when considerable remnants remain after surgery, spontaneous shrinkage and relief of mass lesion symptoms can sometimes occur. The aim of this study was to assess shrinkage of tumor residues after transsphenoidal surgery and to identify predictors of tumor shrinkage. Methods A total of 140 patients with postoperative remnants of Nonfunctioning Pituitary Adenomas treated at the Department of Neurosurgery, University Hospital Erlangen, Erlangen, Germany, were included in this study. All patients underwent transsphenoidal procedures with guidance by 1.5-T intraoperative MRI. The intraoperative images of remnants were compared with images taken at 3 months and at 1 year after surgery. The possible predictors analyzed were age; sex; preoperative and intraoperative tumor dimensions; tumor growth pattern; endocrinological, ophthalmological, and histological character...
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the somatostatin analogue octreotide confers sensitivity to rapamycin treatment on Pituitary tumor cells
Cancer Research, 2010Co-Authors: V Cerovac, Jose Monteseringarcia, Hadara Rubinfeld, Michael Buchfelder, Marco Losa, Tullio Florio, Marcelo Paezpereda, Gunter K Stalla, Marily TheodoropoulouAbstract:Rapamycin and its analogues have significant antiproliferative action against a variety of tumors. However, sensitivity to rapamycin is reduced by Akt activation that results from the ablative effects of rapamycin on a p70 S6K-induced negative feedback loop that blunts phosphoinositide 3-kinase (PI3K)-mediated support for Akt activity. Thus, sensitivity to rapamycin might be increased by imposing an upstream blockade to the PI3K/Akt pathway. Here, we investigated this model using the somatostatin analogue octreotide as a tool to decrease levels of activated Ser(473)-phosphorylated Akt (pAkt-Ser(473)) in Pituitary tumor cells that express somatostatin receptors. Octreotide increased levels of phosphorylated insulin receptor substrate-1 that were suppressed by rapamycin, subsequently decreasing levels of pAkt-Ser(473) through effects on phosphotyrosine phosphatase SHP-1. Octreotide potentiated the antiproliferative effects of rapamycin in immortalized Pituitary tumor cells or human Nonfunctioning Pituitary Adenoma cells in primary cell culture, sensitizing tumor cells even to low rapamycin concentrations. Combined treatment of octreotide and rapamycin triggered G(1) cell cycle arrest, decreasing E2F transcriptional activity and cyclin E levels by increasing levels of p27/Kip1. These findings show that adjuvant treatment with a somatostatin analogue can sensitize Pituitary tumor cells to the antiproliferative effects of rapamycin.
Sven Berkmann - One of the best experts on this subject based on the ideXlab platform.
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sellar toxoplasmosis and Nonfunctioning Pituitary Adenoma
World Neurosurgery, 2015Co-Authors: Sven Berkmann, Ingeborg Fischer, Beat Sonderegger, Stefan Fischli, Javier FandinoAbstract:Background Sellar toxoplasmosis is associated with congenital infections or immunodeficiency. The finding of Toxoplasma bradycysts in a Pituitary Adenoma is very unusual. Case Description An otherwise healthy 27-year-old woman presented with secondary amenorrhea and moderately elevated prolactin levels. A macroprolactinoma was suspected on magnetic resonance imaging, and cabergoline was initiated. Although dopamine levels decreased, the tumor did not show significant shrinkage; after 2 years, transsphenoidal resection was indicated to clarify the diagnosis and to cure hyperprolactinemia. Histology showed an inactive Pituitary Adenoma and Toxoplasma bradycysts. Seropositivity for Toxoplasma gondii, but neither immunodeficiency nor intracerebral spread, was found. During a postoperative follow-up period of 15 months, the patient did not show any recurrence. Conclusions Sellar toxoplasmosis in conjunction with Pituitary Adenoma is extremely rare. Nonfunctioning lesions should be suspected in cases of sellar masses and moderate hyperprolactinemia.
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intraoperative high field mri for transsphenoidal reoperations of Nonfunctioning Pituitary Adenoma
Journal of Neurosurgery, 2014Co-Authors: Sven Berkmann, Christopher Nimsky, Rudolf Fahlbusch, Sven Schlaffer, Michael BuchfelderAbstract:Object The loss of anatomical landmarks, frequently invasive tumor growth, and tissue changes make transsphenoidal reoperation of Nonfunctioning Pituitary Adenomas (NFAs) challenging. The use of intraoperative MRI (iMRI) may lead to improved results. The goal of this retrospective study was to evaluate the impact of iMRI on transsphenoidal reoperations for NFA. Methods Between September 2002 and July 2012, 109 patients underwent reoperations in which 111 transsphenoidal procedures were performed and are represented in this study. A 1.5-T Magnetom Sonata Maestro Class scanner (Siemens) was used for iMRI. Follow-up iMRI scans were acquired if gross-total resection (GTR) was suspected or if no further removal seemed possible. Results Surgery was performed for tumor persistence and regrowth in 26 (23%) and 85 (77%) patients, respectively. On the initial iMRI scans, GTR was confirmed in 19 (17%) patients. Remnants were located as follows: 65 in the cavernous sinus (71%), 35 in the suprasellar space (38%), 9 in...
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follow up and long term outcome of Nonfunctioning Pituitary Adenoma operated by transsphenoidal surgery with intraoperative high field magnetic resonance imaging
Acta Neurochirurgica, 2014Co-Authors: Sven Berkmann, Christopher Nimsky, Rudolf Fahlbusch, Sven Schlaffer, Michael BuchfelderAbstract:Background Intraoperative MRI (iMRI) increases gross total resection (GTR) rates in transsphenoidal surgery; however, long-term follow-up data is lacking. The objective is to assess the outcome of patients with Nonfunctioning Pituitary Adenomas (NFA) at a mean follow-up of > 5 years.
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follow up and long term outcome of Nonfunctioning Pituitary Adenoma operated by transsphenoidal surgery with intraoperative high field magnetic resonance imaging
Acta Neurochirurgica, 2014Co-Authors: Sven Berkmann, Christopher Nimsky, Rudolf Fahlbusch, Sven Schlaffer, Michael BuchfelderAbstract:Intraoperative MRI (iMRI) increases gross total resection (GTR) rates in transsphenoidal surgery; however, long-term follow-up data is lacking. The objective is to assess the outcome of patients with Nonfunctioning Pituitary Adenomas (NFA) at a mean follow-up of > 5 years. Patients with NFA operated in a single institution with resection control by a 1.5 T intraoperative magnetic resonance imaging (iMRI) scanner and no previous Pituitary surgery were included. Microscopical transsphenoidal approaches with optional endoscopy were used. The iMRI was chosen for spacious suprasellar or retrosellar and/or invasive tumours. IMRI-scans were made if GTR or if nonresectable remnants were presumed. The patients had a full neuroradiological, endocrinological and ophthalmological follow-up at the institution. Eighty-five patients (67 % male;55 ± 14 years) with a follow-up of 5.6 ± 1.9 years were included. The initial GTR rate on iMRI was 44 %. In 83 %, further resections were possible, resulting in a final GTR rate of 66 %. In invasive tumours, the GTR rate was increased by 29 %. The detection of remnants by iMRI had high sensitivity and specificity (100 %), as opposed to endoscopy (21 %;78 %). During follow-up, four (7 %) tumours recurred and 14 (64 %) remnants grew. The recurrence and regrowth rate were 0.013 and 0.114 patients/years, respectively. Seventy-nine percent of the growing remnants were seen < 5 years postoperatively. The use of iMRI for transsphenoidal resection leads to low recurrence rates. Even in case of invasive tumours, distinctly more patients show long tumour-free follow-ups. Tumour remnants detected by iMRI are at high risk to grow within 5 years after surgery.
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tumor shrinkage after transsphenoidal surgery for Nonfunctioning Pituitary Adenoma
Journal of Neurosurgery, 2013Co-Authors: Sven Berkmann, Sven Schlaffer, Michael BuchfelderAbstract:Object Volume reduction of Nonfunctioning Pituitary Adenomas has been described, for example, after radiotherapy and Pituitary tumor apoplexy. Even when considerable remnants remain after surgery, spontaneous shrinkage and relief of mass lesion symptoms can sometimes occur. The aim of this study was to assess shrinkage of tumor residues after transsphenoidal surgery and to identify predictors of tumor shrinkage. Methods A total of 140 patients with postoperative remnants of Nonfunctioning Pituitary Adenomas treated at the Department of Neurosurgery, University Hospital Erlangen, Erlangen, Germany, were included in this study. All patients underwent transsphenoidal procedures with guidance by 1.5-T intraoperative MRI. The intraoperative images of remnants were compared with images taken at 3 months and at 1 year after surgery. The possible predictors analyzed were age; sex; preoperative and intraoperative tumor dimensions; tumor growth pattern; endocrinological, ophthalmological, and histological character...
Jason P Sheehan - One of the best experts on this subject based on the ideXlab platform.
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congress of neurological surgeons systematic review and evidence based guidelines on the management of patients with Nonfunctioning Pituitary Adenomas executive summary
Neurosurgery, 2016Co-Authors: Manish K Aghi, Garni Barkhoudarian, Jason P Sheehan, Clark C Chen, Maria Fleseriu, Steven A Newman, Joshua Lucas, Christopher Farrell, Ian F DunnAbstract:BACKGROUND: Nonfunctioning Pituitary Adenomas (NFPAs) are the most frequent Pituitary tumors. OBJECTIVE: To create evidence-based guidelines for the initial management of NFPAs. METHODS: A multidisciplinary task force composed of physician volunteers and evidence-based medicine-trained methodologists conducted a systematic review of the literature relevant to the management of NFPAs. To ascertain the class of evidence for the posttreatment follow-ups, the task force used the Clinical Assessment evidence-based classification. RESULTS: Seven topics of importance were chosen for detailed evaluation. The topics addressed include preoperative evaluation, primary treatment, treatment options for residual tumors after surgery, and postoperative patient management. For preoperative patient evaluation, the guideline task force focused on preoperative imaging, preoperative laboratory evaluation, and preoperative ophthalmologic evaluation. For primary treatment, this guideline addresses surgical resection, medical therapy, radiation therapy, the natural history of untreated tumors, surgical methodologies, such as endoscopy, microscopy, or craniotomy, and intraoperative adjuncts like neuronavigation, cerebrospinal fluid diversion, or intraoperative imaging. For residual tumor treatment, the guideline task force evaluated radiation vs observation. Additional topics addressed in this guideline regarding postoperative patient management include the frequency of postoperative imaging, postoperative endocrine evaluation, and postoperative ophthalmologic evaluation. CONCLUSION: Although there is clearly a need for more randomized trials generating higher levels of evidence to help guide physicians managing NFPAs, the existing evidence provided valuable data upon which the guidelines described in the 7 articles generated from this effort are based. The full guidelines document can be located at https://www.cns.org/guidelines/guidelines-management-patients-non-functioning-Pituitary-Adenomas. ABBREVIATION: NFPA, Nonfunctioning Pituitary Adenoma.
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long term outcomes after gamma knife radiosurgery for patients with a Nonfunctioning Pituitary Adenoma
Neurosurgery, 2011Co-Authors: Rupa Gopalan, David Schlesinger, Mary Lee Vance, Edward R Laws, Jason P SheehanAbstract:BACKGROUND Nonfunctioning Pituitary Adenomas recur after microsurgery. Gamma Knife radiosurgery (GKRS) has been used to treat recurrent Adenomas. OBJECTIVE To evaluate the long-term rates of tumor control and development of hypopituitarism in patients with Nonfunctioning Pituitary Adenomas after GKRS. METHODS Forty-eight patients with a Nonfunctioning Pituitary Adenoma treated between 1991 and 2004 at the University of Virginia were studied. All patients had more than 4 years of clinical and imaging follow-up. RESULTS All patients underwent follow-up imaging and endocrine evaluations, with a duration ranging from 50 to 215 months (median, 80.5 months) and 57 to 201 months (median, 95 months), respectively. New hormone deficiency after GKRS occurred in 19 of 48 patients (39%). Corticotropin/cortisol deficiency developed in 8% of patients, thyroid hormone deficiency in 20.8%, gonadotropin deficiency in 4.2%, growth hormone/insulin-like growth factor 1 in 16.7%, and diabetes insipidus in 2%. Panhypopituitarism including diabetes insipidus developed in 1 patient. Overall, control of tumor volume was 83%. Tumor volume decreased in 36 patients (75%), increased in 8 patients (17%), and was unchanged in 4 patients (8%). Tumor volumes greater than 5 mL at the time of GKRS were associated with a significantly greater rate of growth (P = .003) compared with an Adenoma with a volume of 5 mL or less. CONCLUSION GKRS resulted in a high and durable rate of tumor control in patients with a Nonfunctioning Pituitary Adenoma. A higher preoperative tumor volume was associated with an increased rate of tumor growth.
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Radiosurgery for Nonfunctioning Pituitary Adenoma
Journal of Neurosurgery Publishing Group (JNSPG), 2003Co-Authors: Jason P Sheehan, Douglas Kondziolka, John Flickinger, L. Dade LunsfordAbstract:Object Nonfunctioning Pituitary Adenomas comprise approximately 30% of all Pituitary tumors. The purpose of this retrospective study was to evaluate the efficacy and role of gamma knife surgery (GKS) in the treatment of these lesions. Methods The authors conducted a review of cases in which GKS was performed at the University of Pittsburgh between 1987 and 2001. Forty-six patients with Nonfunctioning Pituitary Adenomas and with at least 6 months of follow-up data were identified. In 41 of these patients some form of prior treatment such as transsphenoidal resection, craniotomy and resection, or conventional radiation therapy had been conducted. Five patients were deemed ineligible for microsurgery, and GKS served as the primary treatment modality. Endocrinological, ophthalmological, and radiological responses were evaluated. The mean radiation dose to the margin was 16 Gy. In all patients with microAdenomas and 91% of those with macroAdenomas tumor control was demonstrated after radiosurgery. Gamma knife surgery had essentially equal efficacy in terms of achieving tumor control in cases of Adenomas with cavernous sinus invasion and suprasellar extension. No new endocrinopathies were noted following radiosurgery. In two patients, however, tumor growth and decline in visual function occurred. Conclusions Gamma knife surgery is safe and effective in treating Nonfunctioning Pituitary Adenomas. Radiosurgery may serve as a primary treatment modality in some or as a salvage treatment in others. Treatment must be tailored to meet the patient's symptoms, overall health, and tumor morphometry.
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radiosurgery for residual or recurrent Nonfunctioning Pituitary Adenoma
Journal of Neurosurgery, 2002Co-Authors: Jason P Sheehan, Douglas Kondziolka, John C Flickinger, Dade L LunsfordAbstract:Object. Nonfunctioning Pituitary Adenomas comprise approximately 30% of all Pituitary tumors. The purpose of this retrospective study is to evaluate the efficacy and role of gamma knife radiosurgery (GKS) in the management of residual or recurrent Nonfunctioning Pituitary Adenomas. Methods. A review was conducted of the data obtained in 42 patients who underwent adjuvant GKS at the University of Pittsburgh between 1987 and 2001. Prior treatments included transsphenoidal resection, craniotomy and resection, or conventional radiotherapy. Endocrinological, ophthalmological, and radiological responses were evaluated. The duration of follow-up review varied from 6 to 102 months (mean 31.2 months). Fifteen patients were observed for more than 40 months. The mean radiation dose to the tumor margin was 16 Gy. Conformal radiosurgery planning was used to restrict the dose to the optic nerve and chiasm. Tumor control after GKS was achieved in 100% of patients with microAdenomas and 97% of patients with macroAdenomas...
Marco Losa - One of the best experts on this subject based on the ideXlab platform.
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growth hormone therapy does not increase the risk of craniopharyngioma and Nonfunctioning Pituitary Adenoma recurrence
The Journal of Clinical Endocrinology and Metabolism, 2020Co-Authors: Marco Losa, Laura Castellino, Angela Pagnano, Alessandro Rossini, Pietro Mortini, Roberto LanziAbstract:CONTEXT Recombinant human growth hormone (rhGH) replacement therapy is often prescribed in patients with Nonfunctioning Pituitary Adenoma (NFPA) or craniopharyngioma. OBJECTIVE To study whether rhGH therapy in patients with adult growth hormone deficiency (AGHD) increases the risk of Pituitary tumor recurrence. DESIGN Retrospective, observational study. SETTING Tertiary care center. PATIENTS We studied 283 consecutive patients with AGHD due to NFPA or craniopharyngioma between 1995 and 2018. INTERVENTION rhGH treatment at standard doses was initiated in 123 patients (43.5%). The remaining 160 patients served as controls. MAIN OUTCOME MEASURE Risk of tumor recurrence in rhGH-treated and control patients. RESULTS In univariate analysis, recurrence of the Pituitary tumor was less frequent in rhGH-treated patients (19.5%) than in controls (29.7%; hazard ratio [HR] 0.53, 95% confidence interval [CI] 0.32-0.86; P = .01). Multivariate Cox analysis demonstrated that the risk of tumor recurrence was associated with detection of residual disease at the baseline magnetic resonance imaging (HR 9.17; 95% CI, 4.88-17.22; P < .001) and not having performed radiotherapy (HR 16.97; 95% CI, 7.55-38.16; P < .001), while rhGH treatment was no longer associated with a lower risk of recurrence (HR 0.82; 95% CI, 0.47-1.44; P = .50). CONCLUSIONS We found no association between rhGH replacement and the risk of tumor recurrence in patients with AGHD caused by NFPA or craniopharyngioma. These data add to the mounting evidence that rhGH therapy has a neutral effect on the recurrence of Pituitary tumors. PRECIS Replacement therapy with rhGH is prescribed to patients with adult growth hormone deficiency. Our study found no increased risk of Pituitary tumor recurrence.
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safety of transsphenoidal microsurgical approach in patients with an acth secreting Pituitary Adenoma
Endocrine, 2017Co-Authors: Carmine Antonio Donofrio, Marco Losa, Marco Gemma, Lodoviga Giudice, Lina Raffaella Barzaghi, Pietro MortiniAbstract:Purpose Patients affected by Cushing’s disease often have important comorbidities directly linked to hypercortisolism that might enhance the operative risk. We report the safety of transsphenoidal surgery in patients affected by Cushing’s disease as compared with patients with Nonfunctioning Pituitary Adenoma.
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the somatostatin analogue octreotide confers sensitivity to rapamycin treatment on Pituitary tumor cells
Cancer Research, 2010Co-Authors: V Cerovac, Jose Monteseringarcia, Hadara Rubinfeld, Michael Buchfelder, Marco Losa, Tullio Florio, Marcelo Paezpereda, Gunter K Stalla, Marily TheodoropoulouAbstract:Rapamycin and its analogues have significant antiproliferative action against a variety of tumors. However, sensitivity to rapamycin is reduced by Akt activation that results from the ablative effects of rapamycin on a p70 S6K-induced negative feedback loop that blunts phosphoinositide 3-kinase (PI3K)-mediated support for Akt activity. Thus, sensitivity to rapamycin might be increased by imposing an upstream blockade to the PI3K/Akt pathway. Here, we investigated this model using the somatostatin analogue octreotide as a tool to decrease levels of activated Ser(473)-phosphorylated Akt (pAkt-Ser(473)) in Pituitary tumor cells that express somatostatin receptors. Octreotide increased levels of phosphorylated insulin receptor substrate-1 that were suppressed by rapamycin, subsequently decreasing levels of pAkt-Ser(473) through effects on phosphotyrosine phosphatase SHP-1. Octreotide potentiated the antiproliferative effects of rapamycin in immortalized Pituitary tumor cells or human Nonfunctioning Pituitary Adenoma cells in primary cell culture, sensitizing tumor cells even to low rapamycin concentrations. Combined treatment of octreotide and rapamycin triggered G(1) cell cycle arrest, decreasing E2F transcriptional activity and cyclin E levels by increasing levels of p27/Kip1. These findings show that adjuvant treatment with a somatostatin analogue can sensitize Pituitary tumor cells to the antiproliferative effects of rapamycin.
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early results of surgery in patients with Nonfunctioning Pituitary Adenoma and analysis of the risk of tumor recurrence
Journal of Neurosurgery, 2008Co-Authors: Marco Losa, Pietro Mortini, Raffaella Barzaghi, Paolo Ribotto, Maria Rosa Terreni, Stefania Bianchi Marzoli, Sandra Pieralli, M GiovanelliAbstract:Object Nonfunctioning Pituitary Adenomas (NFPAs) are benign tumors of the Pituitary gland that typically cause visual and/or hormonal dysfunction. Surgery is the treatment of choice, but patients remain at risk for tumor recurrence for several years afterwards. The authors evaluate the early results of surgery and the long-term risk of tumor recurrence in patients with NFPAs. Methods Between 1990 and 2005, 491 previously untreated patients with NFPA underwent surgery at the Universita Vita-Salute. Determinations of recurrence or growth of the residual tumor tissue during the follow-up period were based on neuroradiological criteria. Results Residual tumor after surgery was detected in 173 patients (36.4%). Multivariate analysis showed that invasion of the cavernous sinus, maximum tumor diameter, and absence of tumor apoplexy were associated with an unfavorable surgical outcome. At least 2 sets of follow-up neuroimaging studies were obtained in 436 patients (median follow-up 53 months). Tumors recurred in ...
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gamma knife surgery for treatment of residual Nonfunctioning Pituitary Adenomas after surgical debulking
Journal of Neurosurgery, 2004Co-Authors: Marco Losa, Pietro Mortini, Micol Valle, Alberto Franzin, Camillo Ferrari Da Passano, Marco Cenzato, Stefania Bianchi, Piero Picozzi, M GiovanelliAbstract:Object. Radiation therapy diminishes the risk of recurrence of incompletely removed Nonfunctioning Pituitary Adenoma (NPA). The authors evaluated the efficacy and safety of gamma knife surgery (GKS) in patients with residual NPA following surgical debulking of the tumor. Methods. Fifty-four patients, 26 men and 28 women, ranging in age from 29 to 72 years underwent gamma knife treatment. Baseline and follow-up studies involved magnetic resonance imaging, hormone evaluation, and neuroophthalmological examination 6 and 12 months after GKS and at yearly intervals thereafter. The mean follow up after GKS was 41.1 � 3.1 months. Two of 52 patients undergoing follow up had a recurrence 40 and 49 months after GKS. In both of these patients the treated lesion had reduced in size, but a new lesion appeared in the contralateral side of the sella turcica. The recurrence-free interval at 5 years was 88.2% (95% confidence interval 72.6‐100%). Tumor volume decreased from a baseline value of 2.3 � 0.2 to 1.7 � 0.2 cm 3 at the last follow up (p � 0.001). Twenty-two patients (42.3%) had a 20% or greater reduction in tumor volume. The administered radiation dose had been significantly higher in patients who experienced tumor reduction. Visual function and motility did not deteriorate in any patient. New cases of hypogonadism, hypothyroidism, and hypoadrenalism occurred in 12.5, 8.6, and 2.3%, respectively, of assessable patients at risk. Conclusions. Gamma knife surgery was effective in controlling the growth of residual NPA after previously performed maximal surgical debulking. The major advantage of GKS compared with fractionated radiotherapy seems to be a lower risk of side effects, especially a lower risk of hypopituitarism.
Sven Schlaffer - One of the best experts on this subject based on the ideXlab platform.
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intraoperative high field mri for transsphenoidal reoperations of Nonfunctioning Pituitary Adenoma
Journal of Neurosurgery, 2014Co-Authors: Sven Berkmann, Christopher Nimsky, Rudolf Fahlbusch, Sven Schlaffer, Michael BuchfelderAbstract:Object The loss of anatomical landmarks, frequently invasive tumor growth, and tissue changes make transsphenoidal reoperation of Nonfunctioning Pituitary Adenomas (NFAs) challenging. The use of intraoperative MRI (iMRI) may lead to improved results. The goal of this retrospective study was to evaluate the impact of iMRI on transsphenoidal reoperations for NFA. Methods Between September 2002 and July 2012, 109 patients underwent reoperations in which 111 transsphenoidal procedures were performed and are represented in this study. A 1.5-T Magnetom Sonata Maestro Class scanner (Siemens) was used for iMRI. Follow-up iMRI scans were acquired if gross-total resection (GTR) was suspected or if no further removal seemed possible. Results Surgery was performed for tumor persistence and regrowth in 26 (23%) and 85 (77%) patients, respectively. On the initial iMRI scans, GTR was confirmed in 19 (17%) patients. Remnants were located as follows: 65 in the cavernous sinus (71%), 35 in the suprasellar space (38%), 9 in...
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follow up and long term outcome of Nonfunctioning Pituitary Adenoma operated by transsphenoidal surgery with intraoperative high field magnetic resonance imaging
Acta Neurochirurgica, 2014Co-Authors: Sven Berkmann, Christopher Nimsky, Rudolf Fahlbusch, Sven Schlaffer, Michael BuchfelderAbstract:Background Intraoperative MRI (iMRI) increases gross total resection (GTR) rates in transsphenoidal surgery; however, long-term follow-up data is lacking. The objective is to assess the outcome of patients with Nonfunctioning Pituitary Adenomas (NFA) at a mean follow-up of > 5 years.
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follow up and long term outcome of Nonfunctioning Pituitary Adenoma operated by transsphenoidal surgery with intraoperative high field magnetic resonance imaging
Acta Neurochirurgica, 2014Co-Authors: Sven Berkmann, Christopher Nimsky, Rudolf Fahlbusch, Sven Schlaffer, Michael BuchfelderAbstract:Intraoperative MRI (iMRI) increases gross total resection (GTR) rates in transsphenoidal surgery; however, long-term follow-up data is lacking. The objective is to assess the outcome of patients with Nonfunctioning Pituitary Adenomas (NFA) at a mean follow-up of > 5 years. Patients with NFA operated in a single institution with resection control by a 1.5 T intraoperative magnetic resonance imaging (iMRI) scanner and no previous Pituitary surgery were included. Microscopical transsphenoidal approaches with optional endoscopy were used. The iMRI was chosen for spacious suprasellar or retrosellar and/or invasive tumours. IMRI-scans were made if GTR or if nonresectable remnants were presumed. The patients had a full neuroradiological, endocrinological and ophthalmological follow-up at the institution. Eighty-five patients (67 % male;55 ± 14 years) with a follow-up of 5.6 ± 1.9 years were included. The initial GTR rate on iMRI was 44 %. In 83 %, further resections were possible, resulting in a final GTR rate of 66 %. In invasive tumours, the GTR rate was increased by 29 %. The detection of remnants by iMRI had high sensitivity and specificity (100 %), as opposed to endoscopy (21 %;78 %). During follow-up, four (7 %) tumours recurred and 14 (64 %) remnants grew. The recurrence and regrowth rate were 0.013 and 0.114 patients/years, respectively. Seventy-nine percent of the growing remnants were seen < 5 years postoperatively. The use of iMRI for transsphenoidal resection leads to low recurrence rates. Even in case of invasive tumours, distinctly more patients show long tumour-free follow-ups. Tumour remnants detected by iMRI are at high risk to grow within 5 years after surgery.
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tumor shrinkage after transsphenoidal surgery for Nonfunctioning Pituitary Adenoma
Journal of Neurosurgery, 2013Co-Authors: Sven Berkmann, Sven Schlaffer, Michael BuchfelderAbstract:Object Volume reduction of Nonfunctioning Pituitary Adenomas has been described, for example, after radiotherapy and Pituitary tumor apoplexy. Even when considerable remnants remain after surgery, spontaneous shrinkage and relief of mass lesion symptoms can sometimes occur. The aim of this study was to assess shrinkage of tumor residues after transsphenoidal surgery and to identify predictors of tumor shrinkage. Methods A total of 140 patients with postoperative remnants of Nonfunctioning Pituitary Adenomas treated at the Department of Neurosurgery, University Hospital Erlangen, Erlangen, Germany, were included in this study. All patients underwent transsphenoidal procedures with guidance by 1.5-T intraoperative MRI. The intraoperative images of remnants were compared with images taken at 3 months and at 1 year after surgery. The possible predictors analyzed were age; sex; preoperative and intraoperative tumor dimensions; tumor growth pattern; endocrinological, ophthalmological, and histological character...