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Featured researches published by T. Schreiner.


European Journal of Endocrinology | 2007

Gamma knife stereotactic radiosurgery for acromegaly

Einar Osland Vik-Mo; Marianne Øksnes; Paal-Henning Pedersen; Tore Wentzel-Larsen; Eyvind Rødahl; Frits Thorsen; T. Schreiner; Sylvi Aanderud; Morten Lund-Johansen

BACKGROUND Gamma knife radiosurgery (GKR) is an adjuvant treatment for acromegaly if surgery fails to normalize GH hypersecretion. OBJECTIVE To examine the effect of GKR on tumor growth and hypersecretion, and to characterize the adverse effect of this treatment. DESIGN Cross-sectional follow-up study. First, retrospective data pre- and post-GKR were collected. PATIENTS then underwent a predefined survey including radiological, endocrinological, ophthalmological, and neurosurgical evaluation. SETTING Norwegian National Center for gamma knife treatment. PATIENTS Sixty-one patients treated with GKR for acromegaly. Out of 55, 53 living patients underwent a detailed survey. The mean follow-up was 5.5 years. No patient was lost to follow-up. RESULTS Tumor growth was stopped in all patients. At 3, 5, and 10 years after GKR, 45, 58, and 86% of patients had normal IGF-I levels. Consecutive hormone value analysis showed that patients receiving GH-suppressive medication had a more rapid decline in hypersecretion than those who did not receive such medication. Evaluated by survey baseline values alone, non-elevated IGF-I and GH levels below 5 mIU/l were found in 38%. GH-suppressive medication was terminated in 16 out of 40 patients following GKR. Nine out of 53 surveyed patients (17%) had normal IGF-I and GH nadir below 2.6 mIU/l at glucose tolerance tests, while not on hormone-suppressive medication. Two patients developed minor visual field defects. Eight patients started hormone substitution therapy during the follow-up period. CONCLUSION GKR is an effective adjuvant treatment for residual acromegaly, carrying few side effects.


European Journal of Endocrinology | 2014

Non-pheochromocytoma (PCC)/paraganglioma (PGL) tumors in patients with succinate dehydrogenase-related PCC-PGL syndromes: A clinicopathological and molecular analysis

Thomas G. Papathomas; José Gaal; Eleonora P. M. Corssmit; Lindsey Oudijk; Esther Korpershoek; Ketil Heimdal; Jean-Pierre Bayley; Hans Morreau; Marieke F. van Dooren; Konstantinos Papaspyrou; T. Schreiner; Torsten Hansen; Per Arne Andresen; D F Restuccia; Ingrid van Kessel; Geert J.L.H. van Leenders; Johan M. Kros; Leendert Looijenga; Leo J. Hofland; Wolf J. Mann; Francien H. van Nederveen; Ozgur Mete; Sylvia L. Asa; Ronald R. de Krijger; Winand N. M. Dinjens

OBJECTIVE Although the succinate dehydrogenase (SDH)-related tumor spectrum has been recently expanded, there are only rare reports of non-pheochromocytoma/paraganglioma tumors in SDHx-mutated patients. Therefore, questions still remain unresolved concerning the aforementioned tumors with regard to their pathogenesis, clinicopathological phenotype, and even causal relatedness to SDHx mutations. Absence of SDHB expression in tumors derived from tissues susceptible to SDH deficiency is not fully elucidated. DESIGN AND METHODS Three unrelated SDHD patients, two with pituitary adenoma (PA) and one with papillary thyroid carcinoma (PTC), and three SDHB patients affected by renal cell carcinomas (RCCs) were identified from four European centers. SDHA/SDHB immunohistochemistry (IHC), SDHx mutation analysis, and loss of heterozygosity analysis of the involved SDHx gene were performed on all tumors. A cohort of 348 tumors of unknown SDHx mutational status, including renal tumors, PTCs, PAs, neuroblastic tumors, seminomas, and adenomatoid tumors, was investigated by SDHB IHC. RESULTS Of the six index patients, all RCCs and one PA displayed SDHB immunonegativity in contrast to the other PA and PTC. All immunonegative tumors demonstrated loss of the WT allele, indicating bi-allelic inactivation of the germline mutated gene. Of 348 tumors, one clear cell RCC exhibited partial loss of SDHB expression. CONCLUSIONS These findings strengthen the etiological association of SDHx genes with pituitary neoplasia and provide evidence against a link between PTC and SDHx mutations. Somatic deletions seem to constitute the second hit in SDHB-related renal neoplasia, while SDHx alterations do not appear to be primary drivers in sporadic tumorigenesis from tissues affected by SDH deficiency.


The Journal of Sexual Medicine | 2014

Cross‐Sex Hormone Therapy in Trans Persons Is Safe and Effective at Short‐Time Follow‐Up: Results from the European Network for the Investigation of Gender Incongruence

Katrien Wierckx; Eva Van Caenegem; T. Schreiner; Ira Haraldsen; Alessandra D. Fisher; Kaatje Toye; Jean-Marc Kaufman; Guy T'Sjoen

INTRODUCTION Data on the effects of cross-sex hormone therapy (CHT) are limited due to the low prevalence of gender dysphoria, small number of subjects treated at each center, lack of prospective studies, and wide variations in treatment modalities. AIM The aim of this study is to report the short-term effects of CHT on hormonal and clinical changes, side effects, and adverse events in trans men (female-to-male gender dysphoric persons) and trans women (male-to-female gender dysphoric persons). METHODS This was a multicenter 1-year prospective study in 53 trans men and 53 trans women. Trans men received injections of testosterone undecanoate every 3 months. Trans women younger than 45 years received 50 mg cyproterone acetate (CA) and 4 mg estradiol valerate daily, whereas those older than 45 years received 50 mg CA daily together with 100 μg/24 hours transdermal 17-β estradiol. MAIN OUTCOME MEASURES Sex steroids, prolactin, liver enzymes, lipids, hematocrit, blood pressure, anthropometrics, Ferriman and Gallwey score, and global acne grading scale were measured. Side effects, adverse events, and desired clinical changes were examined. RESULTS No deaths or severe adverse events were observed. Two trans men developed erythrocytosis, and two had transient elevation of the liver enzymes. Trans men reported an increase in sexual desire, voice instability, and clitoral pain (all P ≤ 0.01). Testosterone therapy increased acne scores, facial and body hair, and prevalence of androgenetic alopecia. Waist-hip ratio, muscle mass, triglycerides, total cholesterol (C), and LDL-C increased, whereas total body fat mass and HDL-C decreased. Three trans women experienced transient elevation of liver enzymes. A significant increase in breast tenderness, hot flashes, emotionality, and low sex drive was observed (all P ≤ 0.02). Fasting insulin, total body fat mass, and prolactin levels increased, and waist-hip ratio, lean mass, total C, and LDL-C decreased. CONCLUSIONS Current treatment modalities were effective and carried a low risk for side effects and adverse events at short-time follow-up.


Growth Hormone & Igf Research | 2010

Body composition, endocrine and metabolic profiles in adults with Prader-Willi syndrome

Rasmus Sode-Carlsen; Stense Farholt; Kai Fr. Rabben; Jens Bollerslev; T. Schreiner; Anne Grethe Jurik; Jens Sandahl Christiansen; Charlotte Höybye

OBJECTIVE Prader-Willi syndrome (PWS) is a complex genetic disease associated with hypothalamic-pituitary dysfunction and severe obesity. The aim of the present study was to describe the relationships between body composition, metabolic and hormonal profiles in PWS adults. METHOD Forty six adults with genetically verified PWS, 25 women and 21 men, median age 28 years were studied. Body composition was evaluated by standard anthropometric procedures and with computed tomography (CT) of the abdomen and at the mid-femur level. CT of abdomen was compared to 22 healthy, unmatched adults. Circulating lipids were measured and oral glucose tolerance test (OGTT) and hormonal screening including GH secretory capacity (GHRH/arginine test) was carried out. RESULTS Median body mass index (BMI) was 27.2 kg/m(2), with women being more obese than men. Sixteen patients had dyslipidaemia, 10 impaired glucose tolerance and seven had diabetes. Fifty percent were hypogonadal and six fulfilled BMI related criteria for growth hormone deficiency (GHD). Visceral to subcutaneous abdominal fat ratio was reduced in PWS. Visceral abdominal fat fraction correlated with both subcutaneous fat, BMI and peak GH-response. Thigh muscle volume was about half of the thigh fat volume. Beneficial effects of sex-steroid replacement on body composition were not observed. CONCLUSIONS Body fat was primarily located subcutaneously and metabolic consequences of obesity limited. The abnormal body composition similar to that in non-PWS GHD adults increases the interest of GH treatment in the prevention of obesity in adults with PWS.


The Journal of Clinical Endocrinology and Metabolism | 2010

One Year of Growth Hormone Treatment in Adults with Prader-Willi Syndrome Improves Body Composition: Results from a Randomized, Placebo-Controlled Study

Rasmus Sode-Carlsen; Stense Farholt; Kai Fr. Rabben; Jens Bollerslev; T. Schreiner; Anne Grethe Jurik; Jens Sandahl Christiansen; Charlotte Höybye

CONTEXT Prader-Willi syndrome (PWS) is a multisymptomatic disease that shares many similarities with the GH deficiency syndrome, including altered body composition with more body fat than lean body mass. OBJECTIVE Our objective was to investigate the effect of GH on body composition in adults with PWS. DESIGN AND PATIENTS Forty-six adults with PWS were randomized to GH or placebo treatment for 12 months in a double-blind trial. MAIN OUTCOME MEASURES We evaluated change in regional body composition of the abdomen and thigh as measured by computed tomography and change in total body composition as measured by dual-energy x-ray absorptiometry. RESULTS Forty patients completed the study. Baseline median IGF-I sd score was -0.4. GH treatment increased IGF-I by 125 μg/liter (1.51 sd score), and based upon computed tomography, body composition improved with a decrease in visceral fat mass of 22.9 ml (P = 0.004), abdominal sc fat mass 70.9 ml (P = 0.003), and thigh fat mass 21.3 ml (P = 0.013), whereas thigh muscle mass increased 6.0 ml (P = 0.005). By dual-energy x-ray absorptiometry, lean body mass improved 2.25 kg (P = 0.005), and total fat mass decreased 4.20 kg (P < 0.001). No major side effects were seen. CONCLUSION Unrelated to the GH-IGF-I levels at baseline, our results showed that long-term treatment with GH effectively improved body composition and represents a safe, potential treatment option, relieving some of the negative consequences of PWS.


Clinical Endocrinology | 2011

Six-month preoperative octreotide treatment in unselected, de novo patients with acromegaly: effect on biochemistry, tumour volume, and postoperative cure.

Sven M. Carlsen; Johan Svartberg; T. Schreiner; Sylvi Aanderud; Øivind Johannesen; Svein Skeie; Morten Lund-Johansen; Stine Lyngvi Fougner; Jens Bollerslev

Objective  Treatment with somatostatin analogues is the primary medical treatment of acromegaly. Controversies still exist whether acute octreotide effect predicts long‐term biochemical effects, tumour regression or surgical cure. This prospective study investigates effect of 6‐month treatment with octreotide long‐acting repeatable (LAR) on insulin‐like growth factor‐1 (IGF‐1) and growth hormone (GH) levels, pituitary function, tumour regression and postoperative cure in de novo acromegalic patients.


European Journal of Endocrinology | 2014

Body composition, bone turnover, and bone mass in trans men during testosterone treatment: 1-year follow-up data from a prospective case-controlled study (ENIGI).

E. Van Caenegem; Katrien Wierckx; Youri Taes; T. Schreiner; Sara Vandewalle; Kaatje Toye; Bruno Lapauw; J.-M. Kaufman; G. T'Sjoen

PURPOSE To assess the evolution of body composition and bone metabolism in trans men during the first year of cross-sex hormonal therapy. METHODS In a prospective controlled study, we included 23 trans men (female-to-male trans persons) and 23 age-matched control women. In both groups, we examined grip strength (hand dynamometer), biochemical markers of bone turnover (C-terminal telopeptides of type 1 collagen (CTX) and procollagen 1 aminoterminal propeptide (P1NP)), total body fat and lean mass, and areal bone mineral density (aBMD) by dual-X-ray absorptiometry (DXA) and fat and muscle area at the forearm and calf, bone geometry, and volumetric bone mineral density (vBMD) by peripheral quantitative computed tomography (pQCT), before treatment and after 1 year of treatment with undecanoate (1000 mg i.m./12 weeks). RESULTS Before hormonal treatment, trans men had similar bone and body composition compared with control women. Testosterone treatment induced in trans men a gain in muscle mass (+10.4%) and strength and loss of fat mass (-9.7%) (all P<0.001) and increased the levels of P1NP and CTX (both P<0.01). Areal and volumetric bone parameters remained largely unchanged apart from a small increase in trabecular vBMD at the distal radius and in BMD at the total hip in trans men (P=0.036 and P=0.001 respectively). None of these changes were observed in the control group. CONCLUSIONS Short-term testosterone treatment in trans men increased muscle mass and bone turnover. The latter may rather reflect an anabolic effect of testosterone treatment rather than bone loss.


European Journal of Endocrinology | 2008

Gamma knife stereotactic radiosurgery of Nelson syndrome

Einar Osland Vik-Mo; Marianne Øksnes; Paal-Henning Pedersen; Tore Wentzel-Larsen; Eyvind Rødahl; Frits Thorsen; T. Schreiner; Sylvi Aanderud; Morten Lund-Johansen

OBJECTIVE Gamma knife radiosurgery (GKR) can be used as primary or adjuvant therapy for the treatment of an ACTH-producing pituitary tumor after bilateral adrenalectomy, called Nelson syndrome (NS). We have examined the effect of GKR on tumor growth and ACTH-hypersecretion, and characterized the adverse events of this treatment in patients with NS. DESIGN Cross-sectional follow-up study. First, retrospective data pre- and post-GKR were collected. Patients then underwent a predefined survey including radiological, endocrinological, ophthalmological, and neurosurgical evaluation. SUBJECTS Ten patients treated with GKR for NS after previous bilateral adrenalectomy. The mean follow-up was 7 years. No patient was lost to follow-up. RESULTS Tumor growth was stopped in all patients. The ACTH levels declined in eight patients, and normalized in one patient. There was a significant drop in ACTH levels, with a half-time of 2.8 years. No patient developed visual field defects or any other cranial nerve dysfunction as a result of treatment. Four patients started hormone substitution therapy during the follow-up period. The substitution therapy of three pituitary axes present at GKR treatment could be stopped during the same period. One patient developed a glioblastoma in the left parieto-occipital region 14 years after GKR, far from the field of treatment. As the radiation level was below 1Gy to this area, it is unlikely that the GKR treatment itself induced the malignant tumor. CONCLUSION In patients with NS, GKR is an effective adjuvant treatment, carrying relatively few adverse effects. Although the risk of developing a secondary neoplasia after GKR is present, it is probably extremely low.


Growth Hormone & Igf Research | 2012

Growth hormone treatment for two years is safe and effective in adults with Prader-Willi syndrome.

Rasmus Sode-Carlsen; Stense Farholt; Kai Fr. Rabben; Jens Bollerslev; T. Schreiner; Anne Grethe Jurik; Jan Frystyk; Jens Sandahl Christiansen; Charlotte Höybye

OBJECTIVE Prader-Willi syndrome (PWS) shares similarities with the growth hormone (GH) deficiency syndrome in regards to reduced lean body mass and increased fat mass and several short-term trials with GH treatment have demonstrated beneficial effects on body composition. The aim of the present study was to evaluate the effects and safety of two years of GH therapy in adults with PWS. DESIGN Forty-three adults (24 women) with genetically verified PWS were included. Blood samples, body composition as measured by computed tomography (CT) and dual-energy x-ray absorptiometry (DXA) were performed at baseline and during two years of continued GH treatment. RESULTS Thirty-nine patients completed treatment for two years. The GH dosage averaged 0.61 mg/day (range 0.2-1.6). Based upon CT, body composition improved at two years; thigh muscle volume increased 6.7 mL (3.7 to 9.7; P<0.001) whereas abdominal subcutaneous fat volume decreased by 53.3 mL (13.8 to 92.9; P=0.01). By DXA, lean body mass improved 2.8 kg (1.9 to 3.6; P<0.001), whereas fat mass decreased by 3.0 kg (1.1 to 4.8; P=0.003). Lung function as evaluated by peak expiratory flow increased 12% (p<0.001) - indicating improved muscle function. Adverse effects were few. Fifteen out of 39 patients had diabetes (DM; n=4) or impaired glucose tolerance (IGT; n=11) prior to GH treatment. Among the 11 patients with IGT, three reverted to normal glucose tolerance, while three progressed to overt DM at two years of GH treatment. CONCLUSION The known beneficial effects of GH treatment upon body composition in PWS are maintained during two years continuous treatment. With appropriate control, GH is a safe treatment option in adults with PWS.


Acta Neurochirurgica | 2011

Intra-operative MRI facilitates tumour resection during trans-sphenoidal surgery for pituitary adenomas

Jon Ramm-Pettersen; Jon Berg-Johnsen; Per Kristian Hol; Sumit Roy; Jens Bollerslev; T. Schreiner; Eirik Helseth

BackgroundDuring trans-sphenoidal microsurgical resection of pituitary adenomas, the extent of resection may be difficult to assess, especially when extensive suprasellar and parasellar growth has occurred. In this prospective study, we investigated whether intra-operative magnetic resonance imaging (iMRI) can facilitate tumour resection.MethodsTwenty patients with macroadenomas, (16 non-functioning, three growth-hormone secreting and one pharmaco-resistant prolactinoma) were selected for surgery in the iMRI. The mean tumour diameter was 27 mm (range 11–41). The mean parasellar grade, according to the Knosp classification, was 2.3. Pre-operative coronal and sagittal T1-weighted and T2-weighted images were obtained. The trans-sphenoidal tumour resection was performed at the edge of the tunnel of a Signa SP 0.5-Tesla MRI. The surgeon aimed at a radical tumour resection that was followed by a peri-operative MRI scan. When a residual tumour was visualised and deemed resectable, an extended resection was performed, followed by another MRI scan. This procedure was repeated until the imaging results were satisfactory. In all patients, we were able to obtain images to assess the extent of resection and to classify the resection as either total or subtotal.ResultsAfter primary resection, eight out of 20 cases were classified as total resections. A second resection was performed in 11 of 12 cases classified as subtotal resections, and in four of these, total resection was achieved. A third resection was performed in three of the remaining seven cases with subtotal resections, but we did not achieve total resection in any of these cases. Therefore, the use of iMRI increased the number of patients with total resection from 8/20 (40%) to 12/20 (60%). The only observed complication was a transient spinal fluid leakage.ConclusionIntra-operative MRI during trans-sphenoidal microsurgery is useful in selected patients for a safe and more complete resection.

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Ira Haraldsen

Oslo University Hospital

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Katrien Wierckx

Ghent University Hospital

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Maartje Klaver

VU University Medical Center

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Guy T'Sjoen

Ghent University Hospital

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Charlotte Höybye

Karolinska University Hospital

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Kaatje Toye

Ghent University Hospital

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Chantal Wiepjes

VU University Medical Center

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