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Objective: To investigate the changes in semen quality and bioavailable testosterone concentrations in acromegalic male patients according to their disease activity and compare them with patients with non-functional pituitary adenoma (NFA) and healthy controls (HC)., Methods: Twenty-four acromegalic patients with active disease, 22 acromegalic patients in remission, 10 HCs, and 10 patients with NFA were included., Results: Total and calculated bioavailable testosterone concentrations were lower in patients with pituitary disease. Patients with acromegaly had more severely impaired total testosterone levels and semen parameters in comparison to HCs and patients with NFA. The degree of impairment was more prominent in acromegalic patients with active disease than acromegalic patients in remission. Acromegalic patients in remission had residual impairments in both semen quality and testosterone concentrations. Patients with NFA had the lowest concentrations of calculated bioavailable testosterone, followed by acromegalic patients with active disease and acromegalic patients in remission. Increasing growth hormone (GH) levels were found to be associated with both more severely impaired semen quality and androgen concentrations., Conclusion: Growth hormone hypersecretion can disturb reproductive biology and thereof semen quality. The reduction in semen quality and androgen levels may not fully recover upon disease control. Clinicians should be aware of the increased risk of impaired semen parameters and reduced total/bioavailable levels in acromegalic patients, especially in the setting of active disease., (© 2021. Italian Society of Endocrinology (SIE).)

Background: Regarding the inconclusive results of previous investigations, this study aimed to determine the association between pathology, as a possible predictor, with remission outcomes, to know the role of pathology in the personalized decision making in acromegaly patients., Methods: A retrospective cohort study was performed on the consecutive surgeries for growth hormone (GH) producing pituitary adenomas from February 2015 to January 2021. Seventy-one patients were assessed for granulation patterns and prolactin co-expression as dual staining adenomas. The role of pathology and some other predictors on surgical remission was evaluated using logistic regression models., Results: Among 71 included patients, 34 (47.9%) patients had densely granulated (DG), 14 (19.7%) had sparsely granulated (SG), 23 (32.4%) had dual staining pituitary adenomas. The remission rate was about 62.5% in the patients with SG and DG adenomas named single staining and 52.2% in dual staining groups. Postoperative remission was 1.53-folds higher in the single staining adenomas than dual staining-one (non-significant). The remission rate was doubled in DG group compared to two other groups (non-significant). By adjusting different predictors, cavernous sinus invasion and one-day postoperative GH levels decreased remission rate by 91% (95% CI: 0.01-0.67; p = 0.015) and 64% (95% CI: 0.19-0.69; p < 0.001), respectively. Responses to the medications were not significantly different among three groups., Conclusion: Various pathological subtypes of pituitary adenomas do not appear to have a predictive role in estimating remission outcomes. Cavernous sinus invasion followed by one-day postoperative GH is the strongest parameter to predict biochemical remission., (© 2021. The Author(s).)

Background: Acromegaly is a rare, chronic disorder that mostly results from growth hormone (GH)-secreting pituitary adenoma. Transsphenoidal surgery is the first-line treatment of this adenoma. This study aimed to identify factors associated with remission outcome in patients with GH-secreting pituitary adenomas following transsphenoidal surgery., Methods: Patients with GH-secreting pituitary adenomas who underwent transsphenoidal surgery for tumor removal at Songklanagarind Hospital between January 2003 and December 2019 were retrospectively reviewed. The primary outcome was the remission of disease at the last follow-up using 2000 and 2010 consensus criteria. Using logistic regression analysis, various factors were analyzed for association with disease remission outcome., Results: This study included 51 patients. The remission rate of GH-secreting pituitary microadenomas and macroadenomas following transsphenoidal surgery were 100% and 43.75%, respectively. Multivariate analysis showed that preoperative insulin-like growth factor 1 index ≥2.5 and Knosp classification grade 3-4 were significantly associated with nonremission outcome (P < 0.001 and P = 0.012, respectively). Patients with both of these factors had poor outcomes and never achieved remission after treatment, while patients with neither of these factors had high remission rates (87.5%) following surgery. Four of 6 (66.7%) patients who underwent repeat surgery gained remission., Conclusions: Preoperative insulin-like growth factor 1 index ≥2.5 and Knosp classification grade 3-4 were important prognostic factors that determined remission outcome after treatment. Patients who have both of these poor prognostic factors should be aggressively treated with surgery, medication, and probably radiation to optimally control the disease., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Objective: In this study, we considered to assess the presence of estrogen receptors (ER) and the expression of estrogen receptor genes (ESR) in the surgical tissue samples of acromegaly patients and the control group patients with nonfunctioning adenoma and their association with disease activity. We also aimed to determine the significance of ER positivity in acromegaly patients and to find out whether it carries a potential to be used as a predictor of prognosis and therapy regimen in the future., Design: This study was conducted on a total of 67 patients over 18 years of age. The study group consisted of 34 patients with acromegaly and 33 patients with nonfunctioning pituitary adenoma. The pre- and post-operative basal pituitary hormone levels and magnetic resonance images (MRI) of all patients, as well as their remission status of all acromegaly patients were evaluated. Immunohistochemical (IHC) staining procedures for ER-α were performed on surgical tissue samples. Real-time quantitative polymerase chain reaction (RT-qPCR) method was used to determine the levels of ESR1 and ESR2 gene expressions., Results: We found that IHC staining for ER-α was positive in 31.3% and 45.5% of the patients with acromegaly and nonfunctioning adenoma respectively. There was no statistically significant difference of ER-α positivity, ER-α immunoreactivity score and ESR1/ESR2 gene expression levels among the study groups (p > .05). Nevertheless, the expression of ESR1 gene was found to be 0.26 times more, and the ESR2 gene to be 0.11 times less in the acromegaly group compared to those of the nonfunctioning adenoma group. Additionally, we detected the positivity of ER-α only in acromegaly patients who were in remission. An inverse association was found between the pre-operative insulin-like growth factor-1 (IGF-1) levels and the expressions of ESR1/ESR2 gene in acromegaly patients. So these results indicated that the high ESR1 and ESR2 gene expressions in acromegaly patients are associated to the decrease of pre-operative IGF-1 values. Also an inverse association was found between the pre-operative adenoma volume and ESR1 Ct values, means that increase in ESR1 gene expression is associated to the decrease of adenoma volume., Conclusions: The current results may suggest the use of these parameters as useful prognostic markers because all ER-positive acromegaly patients were in remission and the high ESR1 and ESR2 gene expressions in acromegaly patients is associated to the decrease of pre-operative IGF-1 values. Our results need to be supported by further studies., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Growth hormone (GH) exerts a diverse set of effects across many tissues including fat, muscle, bone, kidney, heart, and liver. GH is also a diabetogenic hormone in that it inhibits the actions of insulin. Acromegaly, a condition traditionally characterized by increased levels of growth hormone secretion as a result of pituitary adenoma, results in increased tissue growth, lipolysis, and can result in patients with hyperglycemia and hyperinsulinemia. While current treatment modalities have greatly improved prognoses for most patients, a significant number present clinical symptoms of acromegaly with elevated levels of IGF-1 in the absence of increased GH levels, a phenomenon known as micromegaly. This condition presents a challenge to most currently used treatments since the high circulating IGF-1 levels are independent of elevated levels of GH. It has been previously shown that advanced glycation end products (AGE) can stimulate IGF-1 secretion by human monocytes in vitro, demonstrating a possible mechanism for increased IGF-1 levels. To further investigate AGE/GH/IGF-1 interaction, we have reanalyzed a publicly available RNAseq dataset from subcutaneous adipose tissue of patients with acromegaly. S100A1, a member of the calgranulin family of proteins and ligand of the AGE receptor, was shown to be significantly upregulated in patients with acromegaly. These findings identify an important consideration that may help explain the counterintuitive nature of micromegaly, while simultaneously providing new insight into the role of GH in diabetic, inflammatory, and immune pathologies., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Pituitary diseases such as acromegaly and Cushing's disease require surgical or medical therapy. In some functioning pituitary tumors, a spontaneous remission of hormonal hypersecretion is observed, mainly associated to apoplexy or pituitary infarction. We report the evolution of two female patients older than 70 years at the time of diagnosis, with multiple comorbidities. In case 1, acromegaly was diagnosed at 74 years of age. Sellar CT scan showed a 10-mm adenoma. During her follow-up, IGF1 levels remained normal. Nine years later, a magnetic resonance (MR) showed a 7-mm adenoma. In case 2, clinical and biochemical diagnosis of Cushing's disease was done being 71 years old. Sellar MR showed a 6-mm adenoma. Three years later, urinary cortisol normalized with no changes in adenoma at MR. Seven years later, she remains without clinical or biochemical signs of hypercortisolism. In both cases, no signs of hemorrhage were observed at MR.

Background: This study was designed to present initial results on clinical presentation, therapeutic modalities, and outcome information of patients with pituitary tumors registered in Iran Pituitary Tumor Registry (IPTR)., Methods: We collected data from a web-based electronic medical records of patients with various pituitary tumors referred to four tertiary care centers in the country. Retrospective analysis was performed on demographic, clinical, and therapeutic information of 298 patients including 51 clinically nonfunctioning adenoma (CNFA), 85 acromegaly, 135 prolactinoma, and 27 Cushing's disease (CD)., Results: From October 2014 to July 2016, 298 people with the diagnosis of pituitary tumor were registered. Prolactinoma was the most prevalent tumor (45.3%), followed by Acromegaly (28.6%), CNFPA (17.1%), and CD (9%). Female dominance was seen among patients with prolactinoma and CD, while the majority of patients with CNFPA were male and acromegaly was equally distributed between men and women. Hypogonadal symptoms were almost always seen in all types of pituitary groups. Surgery alone was the most common therapeutic modality used in cases of acromegaly, CNFPA, and CD. However, medical therapy alone was frequently applied for cases of prolactinoma. Finally, biochemical cure was achieved in most cases of prolactinoma and CD, but only in 36.5% of acromegalics. Moreover, 80% of patients suffering from CNFPA showed no residual tumor in their imaging., Conclusion: In conclusion, this comprehensive tumor registry enables early identification, selection of best therapeutic approaches, and evaluation of long-term treatment outcomes. Furthermore, this registry can be used to improve surveillance protocols., (2017 The Author(s). This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.)

Pituitary adenoma apoplexy is a well-known clinical syndrome induced by insulin infusion, cardiac surgery, trauma, and hypothalamic releasing factors. Pituitary apoplexy can cause secondary cerebral infarct and internal carotid artery occlusion. With blockade of tumor perfusion, apoplexy triggers a sudden onset of headache, visual impairment, cranial nerve palsy, disturbances of consciousness, eyelid ptosis, and hemiparesis. However, pituitary adenoma cells with high metabolic demand cannot survive with deficient blood supply and glucose concentrations. Moreover, a number of case reports have shown that spontaneous remission of syndromes, such as acromegaly, may be caused by pituitary adenoma after apoplexy. Therefore, understanding mechanism that underlies the balance between pituitary adenoma apoplexy and subsequent spontaneous remission of syndromes may suggest new approaches for treatment of pituitary adenoma apoplexy.

Secreting pituitary adenomas that cause acromegaly and Cushing's disease, as well as prolactinomas and thyrotroph adenomas, are uncommon, usually benign, slow-growing tumours. The rarity of these conditions means that their diagnosis is not familiar to most non-specialist physicians. Consequently, pituitary adenomas may be overlooked and remain untreated, and affected individuals may develop serious comorbidities that reduce their quality of life and life expectancy. Because many signs and symptoms of pituitary adenomas overlap with those of other, more common disorders, general practitioners and non-endocrinology specialists need to be aware of the "red flags" suggestive of these conditions. A long duration of active disease in patients with secreting pituitary adenomas is associated with an increased risk of comorbidities and reduced quality of life. Appropriate treatment can lead to disease remission, and, although some symptoms may persist in some patients, treatment usually reduces the incidence and severity of comorbidities and improves quality of life. Therefore, correct, early diagnosis and characterization of a pituitary adenoma is crucial for patients, to trigger timely, appropriate treatment and to optimize outcome. This article provides an overview of the epidemiology of hormonal syndromes associated with pituitary adenomas, discusses the difficulties of and considerations for their diagnosis, and reviews the comorbidities that may develop, but can be prevented, by accurate diagnosis and appropriate treatment. We hope this review will help general practitioners and non-endocrinology specialists to suspect secreting pituitary adenomas and refer patients to an endocrinologist for confirmation of the diagnosis and treatment.

Objective: The glomerular filtration rate (GFR) is increased in patients with active acromegaly. The aim of this study is to elucidate whether renal function deteriorates in patients with acromegaly and whether this deterioration is reversible after surgical remission., Design/methods: A case-control study of 48 acromegalic patients who were surgically cured (cases) and 48 patients with nonfunctioning pituitary adenomas (NFomas, controls) was conducted. We performed clinical and biochemical examinations before surgery and 3months post-surgery. The GFR of each patient was estimated (estimated GFR, eGFR) using their serum creatinine, age, sex, and body surface area, and postoperative changes in the eGFR were assessed., Results: The preoperative eGFR was significantly higher in patients with acromegaly than in those with NFoma (99.8 vs 75.1mL/min respectively, P<0.01). In acromegalic patients, surgical remission was accompanied by a significant decline in the eGFR (from 99.8 to 86.2mL/min, P<0.01). Conversely, in patients with NFoma, the postoperative eGFR did not change significantly (from 75.1 to 81.9mL/min, P=0.12). Among the acromegalic patients, the postoperative decreases in the eGFR were more prominent in patients with a preoperatively high or normal vs low eGFR., Conclusions: Our data demonstrated a significant post-surgical eGFR decrease in patients with acromegaly, but not in patients with NFomas. This change in the eGFR was reversible in acromegalic patients with a high/normal preoperative eGFR, but not in those with a low preoperative eGFR. This suggests that the reversible pathophysiological change in some patients is functional but not organic., (© 2016 European Society of Endocrinology.)

Purpose: To compare hypothalamus-pituitary-adrenal (HPA) axis integrity at diagnosis and recovery after transsphenoidal surgery (TSS), in acromegaly patients, compared with tumor size matched non-functioning adenoma (NFA) patients., Methods: A retrospective 7-year evaluation of acromegaly patients, who underwent TSS with 52 weeks follow-up at a single institution, was undertaken. 50 acromegaly with complete follow-up data at all points and 50 NFA patients were matched for tumor size; HPA axis was similarly assessed pre-operatively and at 6, 12 and 52 weeks post-operatively. Recovery of HPA axis and gender specific prevalence of adrenal insufficiency (AI), were analyzed in both groups. We also studied AI in acromegaly patients requiring medical therapy post-operatively vs those in remission after surgery., Results: AI remained less prevalent in acromegaly vs NFA (acromegaly, p = 0.01; NFA, p = 0.15) at 52 weeks after surgery, although the prevalence of AI decreased in both groups from baseline by 52 weeks. Additionally, recovery from baseline AI was significantly greater by 52 weeks in acromegaly patients over NFA patients (p = 0.001). Recovery of HPA axis in acromegaly patients remained significant (p = 0.03) despite the need for medical therapy. AI at baseline was proportionately more prevalent in acromegalic males at baseline (p = 0.002) but no gender difference was apparent at 52 weeks (p = 0.35). Conversely, in NFA patients, no gender difference was apparent pre-operatively (p = 0.49), but AI was more prevalent in males at 52 weeks (p = 0.001)., Conclusion: In the longest comparative study to date using a standard assessment modality, HPA axis recovery was more frequent in acromegaly compared to NFA patients, independent of tumor size, cavernous sinus invasion (CSI), and body mass index (BMI). HPA axis integrity must be carefully and periodically monitored in acromegaly patients during short- and long-term follow-up to prevent overtreatment with glucocorticoids.

In this double case report, we present two special cases of pituitary apoplexy. First, we describe a patient with growth hormone deficiency despite clinical suspicion of acromegaly. Imaging showed evidence of a recent pituitary apoplexy, which might have caused spontaneous remission of the acromegaly before presentation at our outpatient clinic. Second, we describe a patient who presented with spontaneous remission of Cushing's disease after pituitary apoplexy, followed by a spontaneous remission of a relapse of the Cushing's disease due to a second pituitary apoplexy. These cases show that patients in spontaneous remission of hormonally active pituitary adenomas should be suspected of a pituitary apoplexy. Furthermore, even after spontaneous remission following pituitary apoplexy, careful long-term follow-up of these patients is mandatory, as relapses of hormonal hypersecretion can occur.

Background: Previous studies report impaired health-related quality of life (HRQoL) in patients with functional pituitary adenomas (FPA). We assessed HRQoL in FPA patients having undergone surgery at our University Central Hospital between 2000 and 2010, with combined adjuvant treatment given to achieve strict hormonal control., Design: A cross-sectional study including a large control population., Patients and Methods: HRQoL was assessed by the 15D in 100 FPA patients (acromegaly n = 47, Cushing's disease n = 21, prolactinoma n = 26, TSH-adenoma n = 2, gonadotropinoma n = 4), operated on a mean 7·4 (range 2·1-13·0) years earlier. An age- and gender-standardized sample of the general population (n = 4924) served as controls. HRQoL determinants were assessed by independent samples t-test and multiple regression analysis., Results: Hormonal remission rate was 90·9% and 43·9% of the patients received replacement therapy. The mean 15D scores were similar in patients and controls (0·917 vs 0·922, P = 0·568). On single dimensions, patients were worse off regarding speech and sexual activity (both P < 0·05) and better off regarding discomfort and symptoms (P < 0·05). Age (P = 0·001), co-morbidities (P = 0·009), Cushing's disease (P = 0·034), and thyroxine dose (P = 0·002) predicted impaired HRQoL, but not hypopituitarism, hydrocortisone replacement, radiotherapy, or time after surgery., Conclusions: It is possible to achieve near-normal HRQoL in surgically treated FPA patients given adjuvant treatment to achieve strict hormonal remission. However, in addition to age and co-morbidities, Cushing's disease and need for thyroxine replacement therapy predict impaired HRQoL., (© 2014 John Wiley & Sons Ltd.)

Pituitary tumors are the third most common primary intracranial neoplasm. Pathologic proliferation of the somatotrophs results as overproduction of growth hormone presenting as acromegaly. In pituitary adenomas typical visual field (VF) defect is bitemporal hemianopsia but tumor size and optic chiasmal position may cause variable VF defects and VF examination may remain normal. We retrospectively reviewed the medical records of 23 acromegalic patients with pituitary adenomas who received VF tests in the Department of Ophthalmology and Endocrinology, Ondokuz Mayis University Hospital, between 2000 and 2012. Pituitary tumor volume was calculated after performing measurements of tumor diameter in three orthogonal planes using Cavalieri's principle. VF test was performed with a Humphrey field analyzer 750 using a 4-mm² Goldmann size III stimulus. The mean age of the 23 patients (11 male/12 female) was 50.4 ± 11.9 years. 15 patients (65.2 %) had normal VF, two patients (9 %) had quadrantanopsia, three patients (13 %) had hemianopsia and three patients (13 %) had three quadrantanopsia. Among the patients with normal VF, four patients had a suprasellar mass that was elevating the chiasm and spreading along the optic tracts. We also observed VF defects typical of a chiasmal compression even though no suprasellar extension was detected in a few cases. Tumor volume of the patients with VF defects was significantly larger than tumor volume of patients with normal VF (p = 0.02). Tumor volume is an important parameter in VF defects. Advanced neuroimaging assesments should always be complemented in patients even with normal VF.

Patients with active untreated acromegaly show mild to moderate neurocognitive disorders that are associated to chronic exposure to growth hormone (GH) and insulin-like growth factor (IGF-I) hypersecretion. However, it is unknown whether these disorders improve after controlling GH/IGF-I hypersecretion. The aim of this study was to compare neurocognitive functions of patients who successfully underwent GH-secreting adenoma transsphenoidal surgery (cured patients) with patients with naive acromegaly. In addition, we wanted to determine the impact of different clinical and biochemical variables on neurocognitive status in patients with active disease and after long-term cure. A battery of six standardized neuropsychological tests assessed attention, memory and executive functioning. In addition, a quantitative electroencephalography with Low-Resolution Electromagnetic Tomography (LORETA) solution was performed to obtain information about the neurophysiological state of the patients. Neurocognitive data was compared to that of a healthy control group. Multiple linear regression analysis was also conducted using clinical and hormonal parameters to obtain a set of independent predictors of neurocognitive state before and after cure. Both groups of patients scored significantly poorer than the healthy controls on memory tests, especially those assessing visual and verbal recall. Patients with cured acromegaly did not obtain better cognitive measures than naïve patients. Furthermore memory deficits were associated with decreased beta activity in left medial temporal cortex in both groups of patients. Regression analysis showed longer duration of untreated acromegaly was associated with more severe neurocognitive complications, regardless of the diagnostic group, whereas GH levels at the time of assessment was related to neurocognitive outcome only in naïve patients. Longer duration of post-operative biochemical remission of acromegaly was associated with better neurocognitive state. Overall, this data suggests that the effects of chronic exposure to GH/IGF-I hypersecretion could have long-term effects on brain functions.

To study the currently available data of recurrence rates of functioning and nonfunctioning pituitary adenomas following surgical cure and to analyze associated predisposing factors, which are not well established. A systematic literature search was conducted using Medline, Embase, Web of Science and the Cochran Library for studies reporting data on recurrence of pituitary adenoma after surgery, in nonfunctioning adenoma (NF), prolactinoma (PRL) acromegaly (ACRO) and Cushing's disease (CUSH). Of 557 initially retrieved potential relevant studies 143 were selected. Recurrence in NFA was defined as reappearance of tumor on MRI or CT. Increase of hormone levels above normal limits as set by the authors after initial remission was used to indicate recurrence in the functioning tumor types. Remission percentage was lowest in NFA compared with other tumor types (P < 0.001). Surgery-related hypopituitarism was more frequent in CUSH than in the other tumors (P < 0.001). Recurrence, expressed as percentage of the cured population or as ratio of recurrence and total patient years of follow-up was highest in PRL (P < 0.001). The remission percentage did not improve over 3 decades of publications, but there was a modest decrease in recurrence rate (P = 0.04). Recurrences peaked between 1 and 5 years after surgery. Most of the studies with a sufficient number of recurrences did not apply multivariate statistics, and mentioned at best associated factors. Age, gender, tumor size and invasion were generally unrelated to recurrence. For functioning adenomas a low postoperative hormone concentration was a prognostically favorable factor. In NFA no specific factor predicted recurrence. Recurrence rate differs between pituitary adenomas, being highest in patients with prolactinoma, with the highest incidence of recurrence between 1 and 5 years after surgery in all adenomas. Patients with NFA have a lower chance of remission than patients with functioning adenomas. The postoperative basal hormone level is the most important predictor for recurrence in functioning adenomas, while in NFA no single convincing factor could be identified.

Context: The long-term prevalence of adrenal insufficiency after transsphenoidal surgery for GH-secreting pituitary adenomas is unknown. However, recently a single study reported a high prevalence of adrenal insufficiency in acromegalic patients after surgical and/or medical treatment without postoperative radiotherapy., Objective: The objective of the study was to assess the prevalence and incidence rates of adrenal insufficiency in consecutive patients during long-term follow-up after successful transsphenoidal surgery for acromegaly., Design: In 91 consecutive patients in remission after transsphenoidal surgery only, we retrospectively reviewed insulin tolerance tests, CRH stimulation tests, metyrapone tests, and ACTH stimulation tests used to assess corticotrope function., Results: Early postoperatively, insufficient adrenal function was observed in 16 patients (18%), which was transient in eight and irreversible in eight other patients in the first year of postoperative follow-up. Therefore, after the first year, the prevalence of adrenal insufficiency was 9%. Late, new-onset adrenal insufficiency developed in only three patients 13, 18, and 24 yr after surgery. The incidence rate of late adrenal insufficiency after successful surgery was 2/1000 person-years. After long-term follow-up, a median of 8.1 (1-31 yr), the prevalence of secondary adrenal insufficiency was 12% in patients in remission after surgery for acromegaly., Conclusion: The prevalence of adrenal insufficiency 1 yr after surgery was 9%, whereas during prolonged follow-up, the incidence rate of adrenal insufficiency was only 2/1000 person-years in patients in remission after surgery. Therefore, development of late-onset adrenal insufficiency is a very infrequent complication in patients with acromegaly in remission after transsphenoidal surgery only.

GH-producing pituitary adenomas frequently co-produce other certain anterior pituitary hormones, such as prolactin (PRL). In contrast, GH-producing adenomas which express all of corticotropin-releasing factor (CRF), urocorin1 (Ucn1) and urocortin3 (Ucn3) have not been reported. A 39-year-old woman was admitted for evaluation of the pituitary tumor. The diagnosis of acromegaly was confirmed by elevated serum GH and IGF-I levels, and the absence of GH suppression by oral glucose tolerance test. ACTH response to desmopressin (DDAVP) was observed (plasma ACTH levels increased from 13.9 to 50.4 pg/ml at 90 min). Although it is known that ACTH response to DDAVP is considerably useful for the diagnosis of ACTH-dependent Cushing's syndrome, the diagnosis of Cushing's disease was not supported by the criteria. The patient underwent transsphenoidal resection of the pituitary tumor. Immunohistological examination confirmed a GH- and PRL-producing adenoma, whereas ACTH was negative. ACTH response to DDAVP disappeared after tumor removal. To determine the cause of preoperative ACTH response to DDAVP, we examined expression of CRF family peptides and vasopressin V1b receptor in the pituitary adenoma by immunohistochemistry. Immunohistochemistry revealed positive immunostaining for CRF, Ucn1, Ucn3 and vasopressin V1b receptor in the adenoma. These observations raised the possibility that DDAVP caused an ACTH response, perhaps via the paracrine effects of tumor-derived CRF and Ucn1. When ACTH response to DDAVP is observed in patients with pituitary tumor, not only the direct effect of DDAVP on ACTH secretion, but also a possible involvement of CRF and/or urocortins expressed in the pituitary adenoma, should be considered.

Introduction: Insulin-like growth factor-1 (IGF-1) promotes the survival of neurons, mediates neuritic growth, and in 1 clinical trial human recombinant IGF-1 delayed the progression of functional impairment and decline of health-related quality of life in patients with amyotrophic lateral sclerosis (ALS)., Case Report: We describe a case of a 65-year-old woman with a 2-year history of symptoms and signs of acromegaly because of a pituitary microadenoma. The patient posed a challenging diagnostic dilemma because of the presence of dysarthria, which was initially considered as the consequence of acromegaly. After octreotide long-acting release (LAR) treatment, the patient underwent uneventful pituitary surgery. Although postoperative evaluation indicated a cure of acromegaly, progressive bulbar symptoms developed, which were followed by upper limb weakness and muscle atrophy. Neurologic investigations confirmed the diagnosis of ALS and riluzole therapy was given. One year after surgery growth-hormone deficiency was diagnosed, but a trial with human recombinant growth hormone failed to produce any significant improvement. Two years after surgery the patient died of a sudden respiratory arrest. Histopathologic examination of the brain and spinal cord confirmed the diagnosis of ALS., Conclusions: This is the first report showing a rapid progression of ALS after a surgical cure of coexisting acromegaly presumably because of cessation of high endogenous IGF-I levels.

Background: Growth hormone (GH) producing adenomas, frequently express several hormones. This condition could confer them a higher proliferative capacity. Ki-67 is a nuclear protein antigen that is a marker for proliferative activity., Aim: To measure the immunohistochemical hormone expression in pituitary adenomas, excised from patients with acromegaly. To determine if the plurihormonal condition of these adenomas is associated with a higher proliferative capacity, assessed through the expression of Ki-67., Material and Methods: Forty one paraffin embedded surgical samples of pituitary adenomas from patients with acromegalia were studied. Immunohistochemistry for GH, prolactin (PRL), follicle stimulating hormone (FSH), luteinizing hormone (LH), thyroid stimulating hormone (TSH), adrenocorticotropin (ACTH) and for the expression of Ki-67 was carried out., Results: All samples were positive for GH. Twenty seven had positive staining for PRL, 12 had positive staining for glycoproteic hormones and 11 for PRL and one or more glycoproteic hormones. Mean staining for Ki-67 was Z.6+/-3.3%. There were no differences in the expression of this marker between mono or plurihormonal tumors. The expression was neither associated with extrasellar extension., Conclusions: Half of GH producing pituitary adenomas are plurihormonal. There are no differences in the expression of Ki-67 between mono and plurihormonal adenomas.

Objective: To determine whether the somatostatin receptor subtype (SSTR) expression profile correlates with hormonal and tumor volume responses to postsurgical octreotide long acting repeatable (OCT LAR) treatment., Design and Methods: Quantitative real-time RT-PCR was used to evaluate the absolute mRNA copy numbers for all five SSTR subtypes in 22 somatotropinomas. Response to OCT LAR was studied by hormone levels (GH and IGF-I) and tumor volume (sella turcica magnetic resonance imaging)., Results: SSTR5 was present at the highest level followed by SSTR2, SSTR3, SSTR1, and SSTR4 (2327 (1046-5555), 2098 (194-23 954), 97 (0-460), 14 (0-29 480), and 0 (0-652) copies respectively). Positive correlations were found between SSTR2 levels and the percentage decrease of GH and IGF-I after 3 (r=0.49, P<0.027 and r=0.49, P<0.029 respectively) and 6 (r=0.59, P<0.006 and r=0.58, P<0.008 respectively) months of OCT LAR. A negative correlation was found between SSTR5 mRNA levels and the percentage decrease of GH after 3 months of OCT LAR (r=-0.52, P=0.016, n=21). A higher SSTR2/SSTR5 ratio was observed among patients who obtained hormonal control with OCT LAR, when compared with those uncontrolled (2.4 (0.7-10) vs 0.3 (0.1-7.7), P=0.001). A ROC curve analysis showed a SSTR2/SSTR5 ratio of 1.3 as the best predictor of disease control, with a sensitivity of 88% and a specificity of 92% - area under curve, 0.9. A positive correlation was also found between SSTR2 mRNA levels and the percentage decrease in tumor volume after 6 months of OCT LAR (r=0.79, P=0.002, n=12)., Conclusions: Somatostatin receptor subtype 2 mRNA expression levels in somatotropinomas correlate positively with in vivo hormonal and tumor volume responses to OCT LAR.

Several studies have shown that patients with acromegaly have increased mortality rates for cardiovascular disease and cerebrovascular disease (CVD). Similar associations have also been seen for patients with hypopituitarism or with non-functional pituitary adenomas. This review summarizes these data and discusses the relative importance of different risk factors for cardiovascular, especially CVD, mortality among patients with acromegaly or non-functional pituitary adenomas, and for those with hypopituitarism as a result of other causes.

Unlabelled: Survivin has received great attention due to its expression in many human tumours and its potential as a therapeutic target in cancer. Its expression is developmentally regulated: present during fetal development, it is undetectable in terminally differentiated normal adult tissue. Survivin expression has been described to be cell cycle-dependent and restricted to the G2-M checkpoint, where it inhibits apoptosis in proliferating cells., Objectives: The aim of our study was to determine the survivin expression in different types of pituitary adenomas., Methods: Tissue samples were obtained during surgical removal of the tumour from 12 patients with diagnosed: acromegaly in seven cases, non-functioning pituitary tumours in four cases and prolactinoma in one case. Six patients with acromegaly received long-acting somatostatin analogues before tumour resection. After RNA extraction and cDNA synthesis, the amplification of specific survivin's gene fragment was performed., Results: In agreement with the current view that survivin is a tumor-associated antigen, highly expressed in various tumours, we found the presence of survivin expression as a characteristic feature of human pituitary adenomas. The findings of our study demonstrated the presence of an active survivin gene in all twelve analysed pituitary tumours., Conclusions: Based on these findings, we conclude that the estimation of survivin expression in human pituitary tumours may help predict tumour growth and prognosis.

Background: The effect of presurgical long-acting somatostatin analogue (SSA) treatment on operative outcome in acromegaly is as yet uncertain and long-term observations are lacking. We evaluated in an acromegaly case-control study the effect of octreotide pre-treatment on short- and long-term postoperative GH concentrations, pituitary function and glucose tolerance., Methods: 48 patients with a pituitary macro-adenoma - micro- and giant adenomas excluded - were evaluated. 24 patients received presurgical octreotide treatment (secondary surgery, prospectively studied). Another 24 thoroughly matched patients had been operated on without prior octreotide therapy (primary surgery, retrospective evaluation). No patient had received any other treatment prior to operation/octreotide. Standardized testing was performed at diagnosis, following octreotide treatment, after surgery and then yearly for 10.3+/-0.9 yrs (mean+/-SE, primary surgery) and 4.1+/-0.6 yrs (secondary surgery). Immediate and 4-year postoperative results were compared. All work-up was strictly identical in both groups, except for imaging techniques. "Partial remission" was defined as mean GH profile (6-h/7-point) concentration <2.5 microg/L, and "complete remission" as GH nadir <1 microg/L during OGTT plus normal IGF-I concentration (when available)., Findings: The median profile GH (microg/L) values and the OGTT GH nadir values post-surgery (2.4/1.0 vs 1.8/0.7, primary and secondary surgery, resp.) as well as 4 yrs later (2.1/1.15 vs 2.3/0.8) were not significantly different between the groups. The 10-year results of the primary surgery group were not significantly different from its 4-year results. Subgroup analysis of pre-treated patients revealed no significant difference between those with and without tumour shrinkage, or between those with and without parasellar tumour extension. Postoperatively pituitary function was not significantly different between the groups. After 4-years the pituitary-adrenal axis was slightly more impaired in the secondary surgery group rather than following primary surgery, while the pituitary-gonadal axis was not different., Conclusion: Presurgical octreotide treatment has no significant short- or long-term beneficial effect on GH concentration or pituitary function.

Acromegaly is an important area of endocrinology which deserves careful biochemical assessment with growth hormone and IGF-I measurements. Growth hormone suppression during oral glucose tolerance and elevated IGF-I levels form the main diagnostic criteria before treatment has begun. After treatment growth hormone levels during oral glucose tolerance and IGF-I levels are assessed again. A significant proportion (about 30%) are disparate. Thus either having elevated growth hormone levels in the presence of a normal IGF-I or vice versa. Dynamic tests for the diagnosis and monitoring of acromegaly are really not helpful. Assays for growth hormone and IGF-I are changing and absolute levels must be treated with circumspection because of the different assays involved. It is essential for the practicing endocrinologist to know which assays are being used by his or her laboratory for the adequate interpretation of the figures that emanate from it.

First described in 1985, Carney complex is a rare, heritable disorder featuring abnormal skin pigmentation, cardiac and cutaneous myxoma, melanotic schwannoma of psammomatous type, and endocrine abnormalities, including pituitary adenomas. Patients with the latter present with elevated growth hormone (GH) levels and acromegaly or gigantism. Prolactin (PRL) elevation may also be seen. The authors have investigated 2 resected pituitary adenomas from patients with Carney complex. One, a 19-year-old female acromegalic with elevated GH, IgF-1, and PRL levels, had a mammosomatotroph adenoma immunoreactive for GH and PRL. Ultrastructurally, GH and PRL were present in the same secretory granules. The second patient, a 27-year-old acromegalic, had a sparsely granulated GH cell adenoma that by immuno-electron microscopy revealed GH immunoreactivity only. The lack of morphologic similarity between the 2 adenomas indicatesthat pituitary tumors in patients with Carney complex may not exhibit the same phenotype.

The effects of a 12- to 24-month treatment with depot long-acting octreotide (OCT-LAR) on hormone profile, tumor mass, and clinical symptoms were reported in 36 patients with active acromegaly [GH, 34.2 +/- 5.6 microg/L; insulin-like growth factor I (IGF-I), 784.5 +/- 40.4 microg/L]. Fifteen patients were de novo whereas 21 had previously undergone unsuccessful surgery. Serum GH (P < 0.0001) and IGF-I levels (P < 0.0001) significantly decreased as early as after the first injection of OCT-LAR and progressively declined during the 12-24 months of treatment both in de novo and in operated patients. At the last follow-up, GH hypersecretion was controlled (< or =2.5 microg/L) in 69.4% whereas normal IGF-I levels were achieved in 61.1% of patients. GH and IGF-I suppression during OCT-LAR treatment was similar in de novo and operated patients as shown by nadir GH (2.3 +/- 0.6 vs. 2.2 +/- 0.6 microg/L) and IGF-I (323.1 +/- 34.9 vs. 275.5 +/- 33.0 microg/L), percent suppression of GH (92.7 +/- 2.0 vs. 85.9 +/- 3.3%) and IGF-I (57.4 +/- 4.9 vs. 61.5 +/- 4.6%), and prevalence of GH (73.3 vs. 76.2%) and IGF-I (53.3 vs. 71.4%) control. A decrease in tumor volume was observed in 12 of 15 de novo patients, whereas no shrinkage was detected in 4 of 9 operated patients. No patient had tumor reexpansion during OCT-LAR treatment. Significant clinical improvement was obtained in all patients; heart rate, systolic blood pressure, and diastolic blood pressure significantly decreased in the entire population. A mild but significant increase of blood glucose levels, followed by a decrease of serum insulin levels, was observed after 3 months of treatment: this effect subsided with treatment continuation. OCT-LAR treatment was well tolerated by most patients. In conclusion, long-term treatment with OCT-LAR was effective in controlling GH and IGF-I hypersecretion in most patients with acromegaly, when applied either as primary therapy or as adjunctive therapy after surgery. Tumor shrinkage was observed in de novo patients during OCT-LAR treatment, suggesting that it can be successfully applied as primary therapy in patients bearing invasive tumors, who are less likely to be cured after surgery.

Because of persistently elevated growth hormone levels, acromegaly gives rise to various changes in organs mediated by insulin-like growth factor-I. In the heart, it causes myocardial hypertrophy, and, with time, heart failure. The authors performed pituitary adenomectomy in a patient with acromegalic cardiomyopathy who had heart failure; after operation, the blood growth hormone levels decreased to within the normal range and there was a marked improvement in left ventricular function by gated blood pool scintigraphy. Pre- and postoperative fluorine-18 fluorodeoxyglucose (FDG) myocardial positron emission tomography showed increased accumulation of FDG in the myocardium before surgery, but accumulation within the normal range after operation. Myocardial glucose metabolism changed when the long-term effects of growth hormone and insulin-like growth factor-I were eliminated, and this appears to be accurately reflected by FDG positron emission tomography.

In many acromegalic patients the paradoxical release of GH in response to TRH has been well documented, but the mechanisms underlying this phenomenon are not understood. It has been suggested that aberrant GH secretion may result from TRH endogenously synthesized by the adenoma. In 32 adenomas from acromegalic patients, TRH-like immunoreactivity (TRH-LI) was measured using 2 well characterized antisera. TRH-LI was not detectable in 10 samples, and in 19 samples, TRH-LI was measured only by the less specific antibody. With the TRH-specific antibody, TRH-LI was identified only in 3 samples, 2 of which contained exceedingly high concentrations (40 and 96 pg/mg tissue). In the latter 2 samples, prepro-TRH messenger ribonucleic acid was identified by Northern blot analysis, but not in the control tissue sample of a patient without pituitary disease and also not in the other adenomas analyzed by this technique. Transcripts of the TRH receptor were almost undetectable in all adenomas analyzed. For the TRH-degrading ectoenzyme, a potential regulator of TRH signals at adenohypophyseal target sites, transcripts were significantly expressed only in the TRH-producing adenomas. We conclude that the TRH-signaling elements examined are, in general, not directly involved in the mechanisms causing paradoxical GH secretion in acromegalic patients.

Six GH adenomas and three prolactinomas were investigated by light- and electron-microscopic morphological and immunocytochemical methods and the effect of vasoactive intestinal polypeptide (VIP) on growth hormone (GH) and prolactin (PRL) secretion was tested in vitro. The tumour cells of the acromegalic patients revealed both GH and PRL immunoreactivity while prolactinomas showed only PRL activity. All the adenomas stained immunocytochemically also for VIP. By electron microscopy, the tumours included two densely and two sparsely granulated GH, two mixed GH/PRL, and three sparsely granulated PRL adenomas. The dissociated cells were explanted, and cultured in vitro. The cultures in micro test plates were treated with VIP at different concentrations between 10(-5)-10(-12) M. GH and PRL contents in the culture media were measured by radioimmunoassay. GH release was significantly stimulated by VIP in a dose-dependent manner over the whole concentration range, while VIP was effective on the PRL release only at 10(-6)-10(-7) M concentration. The cells of a mixed adenoma were grown in Petri dishes and used for ultrastructural and immunocytochemical studies. The cytoplasmic structure of the cells treated with VIP corresponded to that of active hormone-secreting cells with large ergastoplasmic fields and Golgi zones containing secretory granules. Massive exocytotic events were encountered mainly in the GH-type cells. GH and PRL double immunocytochemistry showed the predominance of GH cells, many of them containing low amounts of PRL as well. Cells predominantly containing PRL were spread among them, they also might contain GH as well. Some of the cells contained only a single immunoreactive hormone. The intensity of gold labelling of the secretory granules appeared higher in the VIP-treated cells than in the untreated control ones which showed a cytoplasmic structure characteristic of glandular cells with low secretory activity. As all the adenoma cells both contained and reacted to VIP, our results are in agreement with an autocrine or paracrine effect of this peptide. The fine structure of the cells in the cultures treated with VIP supply an additional argument to the assumption that VIP may serve as a growth factor for these cell types.

Many studies have shown that acromegaly has relevant effects on cardiovascular system, but few data are available regarding the effects of short-term acromegaly on heart morphology and function. These data would help to clarify the natural history of acromegalic disease and could provide new insight into the mechanisms of GH action on the human heart. Therefore, we studied by Doppler echocardiography a group of 10 young subjects strictly selected as having short-term (<5 yr) uncomplicated acromegaly. The results of this study have shown that shortterm acromegaly is characterized by significantly increased left ventricular mass (P<0.005), with normal relative wall thickness, associated with Doppler indices of diastolic function in the normal range. Furthermore, stroke index and cardiac index were significantly enhanced in the patient group (P<0.01 and P<0.001, respectively), whereas systemic vascular resistance was significantly reduced (P<0.001). In conclusion, our study shows that short-term acromegaly significantly affects the heart, but, at variance with long-term disease, it is characterized by increased left ventricular mass, with eccentric remodeling and normal diastolic function. Moreover, short-term acromegaly induces a high cardiac output state with reduction of systemic vascular resistance.

A prospective study of 48 patients with pituitary adenomas, 19 adenomas causing Cushing's disease, 18 adenomas causing acromegaly, and 11 clinically hormone-inactive adenomas (inactive adenomas), was performed to study emotional disorders occurring before and after transsphenoidal microsurgery. Factors which led to an obvious delay in the diagnostic process were identified. - The tools utilised were an interview and repeated personality assessments. The personality assessments were begun preoperatively and continued for about half a year postoperatively. The interview data, including retrospective statements regarding somatic difficulties, was analysed. - The thesis of a uniform psychopathology due to the influence of elevated hormone levels, and a lack in patients' sensitivity towards their changed appearance in acromegaly could not be confirmed. A high variability of reported emotional problems was found. The most common psychopathological signs for Cushing's disease were excitability and depression, for acromegaly fatigue/loss of energy was the most frequent complaint. Six to eight months postoperatively, a majority of patients noticed an increase of physical well-being. In acromegaly, the time span between first consultation and diagnosis averaged 6.2 years, in Cushing's disease it was 4.3 years, and in inactive adenomas it was 3.9 years. Only a small part of the delay in diagnosis, less than two years, could be attributed to the patients' hesitation to consult a physician.

The purpose of this study was to detect in vitro growth hormone (GH) and prolactin (PRL) secretion from adenomas clinically associated with GH or PRL hypersecretion. The reverse hemolytic plaque assay (RHPA) was applied in order to reveal possible differences among various morphologic adenoma types, and to examine the inhibitory effects of octreotide on GH release as well. The 20 surgically resected pituitary adenomas studied included 15 from acromegalic patients and 5 from patients with hyperprolactinemia. All adenomas were diagnosed by histology, immunocytochemistry and electron microscopy. Among tumors associated with acromegaly, 5 were densely granulated (DG), 5 were sparsely granulated (SG) somatotroph (SM) adenomas, 2 were mammosomatotroph (MSM) and 3 mixed somatotroph-lactotroph cell (mixed SM-LT) adenomas; tumors causing hyperprolactinemia included 4 lactotroph (LT) adenomas and 1 mixed SM-LT adenoma. GH release assessed by the RHPA corresponded to in vivo hormone secretion and to tissue immunoreactivity. Statistical analysis showed significant differences among all morphologic types of SM adenomas, exclusive of SG-SM adenomas compared to mixed SM-LT adenomas. The mean plaque size in DG-SM and MSM adenomas was significantly greater than that of SG-SM and mixed SM-LT adenomas, indicating higher GH secretion by the former two types during the same incubation time. PRL secretion was documented in 2 mixed SM-LT adenomas. Plaques for PRL, but not for GH were formed in all LT adenomas. In all SM and LT adenomas, cells producing large plaques represented a minority of the plaque-forming cell population, however, they accounted for the largest part of the total plaque area, thus the largest part of hormone secretion. Octreotide effects on GH release were studied in 6 adenomas by the RHPA. Octreotide treatment induced a rapid and significant reduction in GH secretion by SM cells in vitro, with a selective effect on high-secreting cells.

Background: A number of surgical series have been reported on the treatment of acromegaly and their results vary widely. The acceptable definition of remission has changed in recent years and it is known, though in a small series, that growth hormone levels of > 5 mU/l are still associated with an increased mortality from the condition. We have analysed data at this centre and examined the outcome of transphenoidal surgery for acromegaly, compared our results with recently published series from other centres and also assessed factors which might effect outcome including whether there is any demonstrable effect of the experience of the surgeon on outcome., Patients and Methods: We have analysed data from all of our 139 patients in whom follow up data are available who have undergone initial transphenoidal surgery for acromegaly by one surgeon at this centre, between 1974 and 1995. Follow up was for a median of 5 years (range 1 month to 17 years)., Results: 67% of patients achieved the criterion for remission (mean GH < 5 mU/l). Success was related to tumour size and preoperative growth hormone values. Thus 91% of patients with microadenomas were in remission postoperatively compared to 46% of patients with macroadenomas. Analysis of the results according to the year of operation showed an improvement in success rates with time. More than 15 years ago, the success rate according to the growth hormone criteria set was 48% and the failure rate 52%. In contrast in the last 5 years analysed, the overall success rate was 74% with a failure rate of 26% (P < 0.04). The success rate for microadenomas was 50% initially, then remained 100%. The case mix was analysed and no change was found. We have also demonstrated an improvement in pituitary function (including normalization of preoperative elevated prolactin) with time so that pre 1981 16% of patients' pituitary function improved perioperatively but 10 years later this figure had risen to 34% (P < 0.03). There was no change over time in the development of pituitary hypofunction, complication rate or recurrence rate., Conclusion: Surgical treatment is a safe and effective treatment for acromegaly and remains the first choice of treatment for most acromegalic patients. The results of this centre compare favourably with series from other centres. We have demonstrated improved results, both in terms of post operative growth hormone values and pituitary function tests with time and increasing neurosurgical experience. We conclude that outcome for the surgical treatment for acromegaly is best achieved with one surgeon specialising in pituitary surgery. Improved operative outcome thus achieved has major cost implications and avoids the necessity for consideration of postoperative radiotherapy and the use of expensive growth hormone suppressing drugs in the postoperative period.

We report our preliminary results after the radiosurgical treatment of 25 secreting pituitary adenomas with a mean follow-up of 20 months (range 6-36 months). Fifteen acromegalic patients showed a decrease of 65% in mean growth hormone (GH) levels after 6 months and of 77% after 12 months. Only 3 patients (20%) are considered to be in remission (mean GH and IGF1 level into the normal range). A decrease of prolactin (PRL) was noted in 46% and 64% at 6 and 12 months after radiosurgery in 4 patients with prolactinomas. There was no case of PRL normalizaion. At present 3/4 patients have individual PRL levels slightly above the normal range. A normalization of Urinary Free Cortisol (UFC) was noticed in 4/6 (66%) patients Cushing's disease within 6-12 months. Pituitary deficiency was noticed in this series in 4/25 patients (16%) who received subtotal or total pituitary irradiation for large postoperative remnants of secreting adenomas poorly defined on magnetic resonance imaging (MRI).

Nitric oxide (NO) has recently been shown to modulate pituitary secretion both in vivo and in vitro. The aim of this study was to investigate the effects of this chemical transmitter on spontaneous and growth-hormone-releasing hormone (GHRH)-induced growth hormone (GH) secretion in acromegalic patients, as well as from GH-secreting tumors maintained in vitro. The study was carried out in 7 acromegalic patients (46.2 +/- 2 years) and in 5 normal subjects (40.1 +/- 1.5 years). GH and prolactin (PRL) secretion were assayed during the administration of isosorbide dinitrate (ID, 5 mg, orally), an NO donor, GHRH, and ID plus GHRH. During ID, a significant (p < 0.05) increase (37%) over basal GH levels was only observed in acromegalics. There was no change in GH levels in response to GHRH or ID plus GHRH in either group. No significant change in PRL levels was observed in either group during ID, while GHRH, with or without ID, induced a slight increase in PRL levels in acromegalics only. Tumor specimens were obtained by selective transsphenoidal adenomectomy, and the cells were plated and incubated for 1, 2 and 24 h in the presence of sodium nitroprusside, a releaser of NO (SNP, 0.3 or 0.6 mM), of GHRH (10-8 M) or of both. SNP significantly (p < 0.001) increased GH levels in a dose-dependent manner (R = 0.99, p = 0.02), but was unable to modify the GH response to GHRH. In acromegalics, a significant correlation (R = 0.822, p < 0.045) and a correlation near the limit of significance (R = 0.73, NS) were observed respectively between the in vivo GH response to ID and the in vitro response to SNP at 24 h. No significant effect was observed on PRL secretion during SNP incubations, while GHRH produced a significant increase in PRL after 2 and 24 h incubation in acromegalics. These observations indicate that NO plays a stimulatory role in vivo and in vitro on GH secretion in acromegalic patients.

With a euglycemic hyperinsulinemic clamp method, whole-body insulin resistance was assessed in 6 cases with acromegaly associated with diabetes mellitus before and after transsphenoidal adenomectomy. The glucose infusion rate (GIR) correlated well with the plasma IGF-I level but poorly with that of GH. Further improvement in insulin sensitivity occurred 3-4 months after operation without substantial changes in plasma levels of both GH and IGF-I or glycemic control. These results indicate that GH excess can induce insulin resistance in association with plasma IGF-I and also through undefined secondary effect.

Pre- and postoperative anterior pituitary function was assessed in 26 subjects with nonfunctioning macroadenoma (NFMA) and in 15 acromegalic subjects with macroadenomas. Preoperatively, NFMA patients had a higher prevalence of secondary hypogonadism (78% vs. 40%; P < 0.05), hypothyroidism (23% vs. 0%; P = 0.06), and hypoadrenalism (43% vs. 7%; P = 0.02) compared to individuals with GH-secreting macroadenoma (GHMA). Patients with NFMA also had a higher prevalence of more severe pituitary failure compared with acromegalic patients; 56% of the patients in this group had more than one pituitary hormone axis impaired compared to only 8% in the acromegalic group. These differences could not be accounted for by tumor grade and/or stage. Transsphenoidal pituitary surgery led to a significant improvement in anterior pituitary function in the NFMA group. Nevertheless, the prevalence of pituitary deficiency postoperatively was still significantly greater in NFMA patients than in the acromegalic group (68% vs. 17%, respectively; P < 0.04). The results suggest that anterior pituitary function is better preserved in GHMA than in NFMA and that this difference is independent of tumor size. The mechanism underlying the lower rate of hypopituitarism in acromegalics with macroadenomas remains to be elucidated.

GH secretion patterns were studied in 14 recently transsphenoidally operated patients by measuring GH concentrations in blood sampled every 10 min over 24 h with a highly sensitive time-resolved immuno-fluorescent assay. Plasma GH concentrations were analyzed with a discrete peak detection program (Cluster) and a multiparameter deconvolution technique. Diurnal variations were analyzed by cosinor analysis. Nine or 10 days after pituitary surgery all patients had a normal plasma insulin-like growth factor-I level, and GH levels were suppressed to below 1.25 micrograms/L in 13 patients and to 1.3 micrograms/L in 1 subject during an oral glucose tolerance test. As we found a highly significant difference in GH secretion between male and female controls, the results obtained in patients were compared with those in their gender- and age-matched controls. Patients with active acromegaly displayed a significantly higher number of deconvolution-estimated secretory bursts (31/24 h in males and 27/24 h in female patients). The estimated secretion rate per 24 h was 25 times greater in female acromegalics and 100 times greater in male acromegalics than that in the controls. In patients with active acromegaly, about 50% of the GH was secreted in a nonpulsatile fashion. In contrast, normal subjects and patients shortly after pituitary surgery secreted GH predominantly (> 99%) in a pulsatile manner. By deconvolution analysis, the mean plasma half-life of GH was 19.7 min in treated male patients and 19.5 min in treated female patients (P = NS vs. controls) estimated mean total GH production/day, 188 micrograms in males and 240 micrograms in females (P = NS vs. controls); number of secretory bursts/24 h, 19.3 in males and 21.9 in females (P = NS vs. controls). In addition, we could not establish any difference in pulse characteristics with Cluster analysis between surgically treated patients and their control subjects. The present data suggest that the basic abnormality of acromegaly resides in the pituitary gland rather than in the hypothalamus.

A study of median nerve sensory conduction at the wrist was performed in 34 patients with pituitary adenomas prior to and following surgery. In 31 patients this was done bilaterally. They included 11 patients with acromegalic features, 3 of whom had features of carpal tunnel syndrome. Six out of 11 (55%) acromegalics had abnormal latencies and conduction velocities pre-operatively. Among the remaining patients only 3 had conduction delay pre-operatively. Postoperative improvement in conduction velocity and latency was recorded in 24 patients although significant improvement was observed in only 13 patients. All 3 patients with carpal tunnel syndrome had significant improvement in conduction velocities and latencies following the surgery. There was no definite relationship between conduction velocity and the pre-operative hormonal profile.

GH concentration profiles in patients with acromegaly are characterized by rapid GH pulsatility and high interpulse GH concentrations. Animal and human studies have shown that GH pulses are consequent upon periodic discharges of hypothalamic GHRH, whereas interpulse GH levels might reflect tonic secretion of hypothalamic SRIH. Thus, the pattern of GH secretion in acromegaly may conceivably be attributed to high GHRH pulse frequency and/or SRIH deficiency. If this assumption is correct, removal of a GH-producing tumor should be followed by a persistently high GH pulse frequency and a high recurrence rate. We have studied pulsatile GH secretion in 12 patients with acromegaly before and after apparently complete removal of their pituitary tumors. Despite normalization of GH secretion after surgery, the disease recurred in 3 patients within 3 yr. The other 9 patients had normal insulin-like growth factor-I and basal and dynamic GH concentrations for 24 +/- 4 months postsurgery. Parameters of GH secretion in this group (pre- and postsurgery) were compared to sex-, age-, and body mass index-matched controls. Plasma GH concentrations in the postoperative and control series were analyzed by a chemiluminescent assay with a sensitivity of 0.01 micrograms/L. Removal of the somatotroph tumor led to normalization of mean and interpulse (but not the nadir) GH levels, pulse amplitude, and responses to GHRH. However, GH pulse frequency (14.2 +/- 1.2 vs. 11.8 +/- 0.9 pulses/24 h) did not change and was significantly (P < 0.001) higher than the control value (8.7 +/- 0.9 pulses/24 h). Thus, SRIH secretion in acromegaly is not inherently deficient, and high interpulse GH levels reflect the mass of tumorous somatotrophs. The persistence of rapid GH pulsatility in apparently "cured" patients with acromegaly suggests that abnormally rapid GHRH pulsatility may be an inherent component of the disease process.

The fundamental frequency of 14 patients undergoing hypophysectomy was studied. Eight patients had acromegaly, 3 had a prolactinoma, and 3 had nonfunctioning adenomas. The fundamental frequency of 22 normal, healthy volunteers was measured for comparison. In addition, the external size of the larynx of all patients and volunteers was measured and a relationship between external laryngeal size and the mean fundamental frequency was identified in the volunteers. The mean fundamental frequency in patients with acromegaly was significantly lower than the other 6 patients undergoing hypophysectomy and, in addition, was also lower than the 22 normal volunteers. Postoperatively the fundamental frequency of the acromegalic patients increased rapidly to within the expected normal range. Patients with acromegaly have a lowered fundamental frequency which is most likely due to altered vocal cord mass and elasticity, which is a reversible change. Patients with acromegaly can expect a rapid and complete return of normal fundamental frequency within 2 weeks of surgery to remove the pituitary adenoma.

We describe, for the first time, a patient with both symptomatic acromegaly and Chiari-I malformation. These conditions could coexist by chance alone, but the probability of both presenting simultaneously in a previously healthy man seem quite remote. Alternatively, acromegaly through associated bony and soft tissue enlargement could lead to the development of symptoms from Chiari-I malformation in this patient.