The biochemical diagnosis of acromegaly: revising the role of measurement of IGF-I and GH after glucose load in 5 questions.

INTRODUCTION: Acromegaly is a rare disorder characterized by the excessive secretion of growth hormone (GH), mostly caused by pituitary adenomas. While in full-blown cases the diagnosis is easy to establish, milder cases are more challenging. Additionally, establishing whether full cure after surgery is reached may be difficult. AREAS COVERED: In this article, we will review the challenges posed by the variability in measurements of GH and its main effector insulin-like growth factor I (IGF-I) due to both biological changes, co-morbidities, and assays variability. EXPERT OPINION: Interpretation of GH and IGF-I assays is important in establishing an early diagnosis of acromegaly, in avoiding misdiagnosis, and in establishing if cure is achieved by surgery. Physicians should be familiar with the variables that affect measurements of these 2 hormones, and with the performance of the assays available in their practice.

Transcription factor immunohistochemistry in the diagnosis of pituitary tumours.

OBJECTIVE: The clinical utility and prognostic value of WHO 2017 lineage-based classification of pituitary tumours have not been assessed. This study aimed to (1) determine the clinical utility of transcription factor analysis for classification of pituitary tumours and (2) determine the prognostic value of improved lineage-based classification of pituitary tumours. METHODS: This was a retrospective evaluation of patients who underwent surgical resection of pituitary tumours at St Vincent's Public and Private Hospitals, Sydney, Australia between 1990 and 2016. Included patients were at least 18 years of age and had complete histopathological data, forming the 'histological cohort'. Patients with at least 12 months of post-surgical follow-up were included in the subgroup 'clinical cohort'. The diagnostic efficacy of transcription factor immunohistochemistry in conjunction with hormone immunohistochemistry was compared with hormone immunohistochemistry alone. The prognostic value of identifying 'higher-risk' histological subtypes was assessed. RESULTS: There were 171 patient tumour samples analyzed in the histological cohort. Of these, there were 95 patients forming the clinical cohort. Subtype diagnosis was changed in 20/171 (12%) of tumours. Within the clinical cohort, there were 21/95 (22%) patients identified with higher-risk histological subtype tumours. These were associated with tumour invasiveness (P = 0.050), early recurrence (12-24 months, P = 0.013), shorter median time to recurrence (49 (IQR: 22.5-73.0) vs 15 (IQR: 12.0-25.0) months, P = 0.005) and reduced recurrence-free survival (P = 0.031). CONCLUSIONS: Application of transcription factor analysis, in addition to hormone immunohistochemistry, allows for refined pituitary tumour classification and may facilitate an improved approach to prognostication.

Early postoperative prediction of both disease remission and long-term disease control in acromegaly using the oral glucose tolerance test.

PURPOSE: Transsphenoidal surgery (TSS) is the cornerstone of acromegaly treatment. Two biochemical parameters, growth hormone (GH) and insulin-like growth factor-1 (IGF-1) levels, sometimes diverge postoperatively; however, it is important to maintain disease control without further treatment, regardless of whether these parameters converge. This study investigated whether remission and long-term disease control could be predicted using early postoperative GH and IGF-1 levels. METHODS: We reviewed 36 consecutive surgically treated patients with acromegaly. IGF-1 levels and minimum GH levels during an oral glucose tolerance test (OGTT) were evaluated at 2 weeks, as well as at 3 months postoperatively. After comparison between the remission and nonremission groups, we analyzed whether early postoperative parameters could predict remission and long-term disease control. RESULTS: Twenty-five patients (69.4%, Group A) achieved remission within 1 year postoperatively. Of the remaining patients (median follow-up period, 53 months), seven (19.5%, Group B) maintained normal IGF-1 levels without treatment, whereas four (11.1%, Group C) required additional treatment. GH levels <1.5 ng/mL measured on the morning after surgery and nadir GH levels <0.7 ng/mL during the OGTT conducted at 2 weeks postoperatively were predictive of remission, with the latter demonstrating 95.2% sensitivity and 100% specificity. All group C patients had nadir GH levels ≥0.7 ng/mL during the OGTT and IGF-1 levels ≥SD +3 at 2 weeks postoperatively. CONCLUSION: Early postoperative nadir GH levels during the OGTT and IGF-1 levels at 2 weeks postoperatively demonstrated excellent predictive value for both endocrinological remission and the necessity for additional treatment.

Discordant GH and IGF-1 Results in Treated Acromegaly: Impact of GH Cutoffs and Mean Values Assessment.

CONTEXT: Discordant growth hormone (GH) and insulin-like growth factor-1 (IGF-1) values are frequent in acromegaly. OBJECTIVE: To evaluate the impact of different GH cutoffs on discordance rate. To investigate whether the mean of consecutive GH measurements impacts discordance rate when matched to the last available IGF-1 value. DESIGN: Retrospective study. SETTING: Referral center for pituitary diseases. PATIENTS: Ninety acromegaly patients with at least 3 consecutive evaluations for GH and IGF-1 using the same assay in the same laboratory (median follow-up 13 years). INTERVENTIONS: Multimodal treatment of acromegaly. MAIN OUTCOME MEASURES: Single fasting GH (GHf) and IGF-1 (IGF-1f). Mean of 3 GH measurements (GHm), collected during consecutive routine patients' evaluations. RESULTS: At last evaluation GHf values were 1.99 ± 2.79 µg/L and age-adjusted IGF-1f was 0.86 ± 0.44 × upper limit of normality (mean ± SD). The discordance rate using GHf was 52.2% (cutoff 1 µg/L) and 35.6% (cutoff 2.5 µg/L) (P = 0.025). "High GH" discordance was more common for GHf <1.0 µg/L, while "high IGF-1" was predominant for GHf <2.5 µg/L (P < 0.0001). Using GHm mitigated the impact of GH cutoffs on discordance (GHm <1.0 µg/L: 43.3%; GHm <2.5 µg/L: 38.9%; P = 0.265). At receiver-operator characteristic curve (ROC) analysis, both GHf and GHm were poor predictors of IGF-1f normalization (area under the curve [AUC] = 0.611 and AUC = 0.645, respectively). The prevalence of disease-related comorbidities did not significantly differ between controlled, discordant, and active disease patients. DISCUSSION: GH/IGF-1 discordance strongly depends on GH cutoffs. The use of GHm lessen the impact of GH cutoffs. Measurement of fasting GH levels (both GHf and GHm) is a poor predictor of IGF-1f normalization in our cohort.

"Non-Classical" Indication for Provocative Testing of Growth Hormone: A Retrospective Cohort Study in Adult Patients Under Replacement Therapy.

BACKGROUND: Adult growth hormone deficiency (GHD) is considered a rare condition. Current guidelines state that GH provocative test is indicated in patients affected by organic hypothalamic/ pituitary disease or with a history of head injury, irradiation, hemorrhage or hypothalamic disease with multiple pituitary deficiencies. Nevertheless, the clinical picture related to GHD may be subtle. OBJECTIVE: We have retrospectively evaluated the indication to GHRH+arginine test in our monocentric cohort of patients treated with hrGH in order to assess whether other conditions had been considered as a rationale for provocative testing. METHODS: Ninety-six patients (51 females and 45 males), aged 19-67 years were included. The GHRH+arginine test had been performed in 29 patients with organic hypothalamic/pituitary disease and in 4 patients for Childhood onset-GHD (CoGHD). In other patients, the diagnosis was suspected for "non classical" reasons in the clinical picture suspected for GHD. RESULTS: Classical indications included previously known primary empty sella (n=15), pituitary surgery (n=14), pituitary cyst (n=1), non-secreting pituitary tumors (n=3) but more than half of the patients (57.3%) had been studied for "non classical" indications: metabolic syndrome (n=25), asthenia (n=13), heart failure (n=4), osteoporosis (n=6), unexplained hypoglycaemia (n=1) and infertility (n=6). The latter represented a significant percentage in the male subgroup under 45 ys. IGF-1 levels were lower than 50th percentile in 63% of patients. Finally, among non-classical reasons, organic pituitary disease was discovered in 22 patients. CONCLUSION: Idiopathic GHD may be unrecognized due to its subtle manifestations and that an extended use of dynamic GH tests may reveal such conditions. A potential field of investigation could be to identify subsets of patients with clinical conditions caused or worsened by underlying unrecognized GHD.

Long-term facial changes and clinical correlations in patients with treated acromegaly: a cohort study.

BACKGROUND: Facial abnormality is the most significant feature in acromegaly patients. However, it is unclear whether and how patient facial appearance improves after treatment. This study aimed to identify 3D facial changes in acromegaly patients after surgical treatment. METHODS: This study included 30 acromegaly patients who underwent resection of a pituitary GH adenoma. The location and extent of facial changes were identified by comparing baseline and 2-year follow-up 3D images of the face. Relationships between facial changes and GH and IGF-1 were evaluated with simple or multivariable linear regression models. RESULTS: Significant soft tissue improvements were observed in acromegaly patients with complete remission, especially in the nose and lip region. Significant reductions in nasal width (3.46 mm, P < 0.001), tip protrusion (1.18 mm, P = 0.003), face curve length (3.89 mm, P = 0.004) and vermilion area (1.42 cm3, P = 0.001) were observed at the 2-year follow-up. Further, changes in nasal width were associated with decreases in GH (ß = 4.440, P = 0.017), the GH nadir (ß = 4.393, P = 0.011) and IGF-1 (ß = 5.263, P = 0.002). The associations were maintained after adjusting for confounders. CONCLUSIONS: Acromegaly patients achieved considerable facial improvements after surgical treatment. The change in nose width was associated with GH and IGF-1 decrease. Better control of patient hormone levels after surgery improves patient facial recovery.

Delayed diagnosis of acromegaly in a patient with focal segmental Glomerulosclerosis: a rare case report and literature review.

BACKGROUND: Experimental studies have demonstrated that hypersecretion of growth hormone (GH) is associated with development of glomerular sclerosis. However, clinical case of such condition is very rare. Here we presented a case of focal segmental glomerulosclerosis (FSGS) associated with acromegaly. CASE PRESENTATION: A 63-year-old man was diagnosed as nephrotic syndrome with minimal change disease for 2 years. Prednisone 1 mg/kg/day for 9 months led to no response. After admission, the second kidney biopsy indicated FSGS (NOS variant). On admission, his acromegalic features were noticed and he complained with a 20-year history of soft tissue swelling of hands and feet. Serum GH and insulin-like growth factor 1 (IGF-1) concentrations were both elevated significantly. An oral glucose tolerance test showed inadequate suppression of serum GH. The presence of a pituitary macroadenoma with a diameter of 1.4 cm by MRI confirmed the diagnosis of acromegaly. Then, the tumor was subtotally removed by trans-sphenoidal surgery. Partial remission of proteinuria was achieved 3 months after surgery and maintained during follow-up, with gradual reduce of corticosteroid. CONCLUSIONS: This rare case suggested that the hypersecretion of GH may participate, at least in part, in FSGS development and progression. Early diagnosis and treatment of acromegaly is beneficial.

The predictors of recovery from diabetes mellitus following neurosurgical treatment of acromegaly: A prospective study over a decade.

OBJECTIVE: The natural history of glucose intolerance (GI) in patients with acromegaly undergoing surgical treatment has not been fully understood. This study was aimed to unravel the prevalence and predictors of recovery from GI in these patients in a prospective multivariate model. MATERIALS AND METHODS: Patients with acromegaly treated between 2007 and 2016 were prospectively studied with respect to demographics, clinicoradiological features, comorbidities, and hormonal investigations before surgery and at regular follow-up. The independent predictors of recovery from diabetes were analyzed. RESULTS: There were a total of 151 patients with active acromegaly included in the study. The median baseline growth hormone (GH) and insulin-like growth factor (IGF)-1 levels were 25 and 811 ng/mL, respectively. Diabetes mellitus (DM) and pre-diabetes were noted in 93 (61.6%) and 20 (13.2%) patients, respectively. Following surgical treatment, the median HbA1c decreased significantly from 6.4% to 5.5% (P < 0.001), with 46.8% having complete recovery from DM or pre-diabetes. This glycemic recovery had significant association with both biochemical (P = 0.001) and radiological remission (P = 0.01). The recovery from DM had a greater association with post-operative IGF-1 than GH, especially among those with discordant GH and IGF-1 levels (60% in normal IGF-1 and high GH vs. 20% in high IGF-1 and normal GH). Post-operative IGF-1 had a significant impact on recovery from DM (P = 0.01) independent of age, body mass index, duration of DM, and pre-operative HbA1c. CONCLUSION: Nearly half of the patients with acromegaly with DM or pre-diabetes had glycemic recovery, influenced by biochemical and radiologic remission. Post-operative IGF-1 appears to be the strongest independent determinant of recovery from DM.

Analgesic effect of long-acting somatostatin receptor agonist pasireotide in a patient with acromegaly and intractable headaches.

A 22-year-old woman presented with worsening vision loss and headaches. A diagnosis of acromegaly was confirmed after detection of an invasive pituitary macroadenoma and biochemical testing. Despite two attempts of surgical debulking of the tumour and administration of long-acting octreotide and cabergoline, growth hormone (GH) and insulin-like growth factor 1 (IGF-1) levels were uncontrolled. The patient experienced persistent headaches despite surgery, gamma knife radiation and ventriculoperitoneal shunt placement; she was then enrolled in the ACCESS trial (ClinicalTrials.gov identifier, NCT01995734). Pasireotide (Signifor; Signifor LAR) was initiated, which led to reduced GH and IGF-1 levels and resolution of her intractable headaches. This highlights the use of monthly pasireotide in resolving headaches and improved biochemical control in a patient with acromegaly. We postulate that the headaches improved due to an analgesic and/or anti-inflammatory effect mediated by somatostatin receptors targeted by pasireotide. This may represent an additional benefit of pasireotide and requires further investigation.

Pitfalls in early biochemical evaluation after transsphenoidal surgery in patients with acromegaly.

Although the current remission criteria for acromegaly are clear and concise, some pitfalls have been reported in early endocrinological evaluation after surgery. To evaluate the long-term (>4 year) outcome and to detect the pitfalls in early evaluation, we retrospectively reviewed 128 patients with acromegaly who underwent primary transsphenoidal surgery during 2011 and 2012. These included 66 men and 62 women, aged from 7 to 76 (mean 46) years old. 49 patients (38.3%) were preoperatively treated with somatostatin analog (SSA). Follow-up period ranged from 52 to 75 (63) months. Long-term remission using the current consensus criteria was achieved in 107 patients (83.6%), 105 of which patient had achieved remission in early evaluation. In 5 patients with preoperative SSA treatment, IGF-1 levels re-elevated more than one year after surgery. Five female patients without pretreatment with SSA showed delayed normalization of IGF-1 between 13 to 27 months postoperatively, two of which patients satisfied the remission criteria. In conclusion, the long-term results can be reliably predicted by the remission criteria early after surgery in most patients with acromegaly. For the accurate evaluation within a year after surgery, however, influence of preoperative treatment with SSA, delayed normalization of IGF-1, and poor GH suppression due to low insulin resistance must be considered, particularly in women.

Can immediate postoperative random growth hormone levels predict long-term cure in patients with acromegaly?

BACKGROUND: Growth hormone (GH) levels following oral glucose tolerance test (OGTT) at 12 weeks or later after surgery have been accepted as the most reliable parameter for defining remission and/or cure in patients with acromegaly. However, the role of random GH in predicting remission in the immediate postoperative period using modern criteria is not known. This study was undertaken to evaluate the role of random GH levels in first 5 postoperative days as an early predictive tool for long-term remission of patients with acromegaly following transsphenoidal pituitary surgery (TSS). PATIENTS AND METHODS: Seventy-five consecutive acromegaly patients with at least three postoperative OGTT values at 3, 6, and 12 months of follow-up were included in the study. GH levels were measured just before surgery, in the immediate postoperative period, at 6 h and on day 1 to day 5 after surgery. Remission was defined as normal age-specific insulin-like growth factor-1 and either basal fasting GH <1 ng/ml or a nadir GH following OGTT <0 .4 ng/ml at 3 months of surgery. RESULTS: Of the 75 patients with acromegaly who underwent TSS, long-term remission was achieved in 42 (56%) patients. GH values ≤1.55 ng/ml at 6 h of surgery showed the highest predictive power for long-term remission, with a sensitivity of 81.2% and a specificity of 83.3%. The duration of disease and tumor volume had no effect on the 6 h GH value-related prediction of cure. CONCLUSION: Early postoperative GH values may be used to predict long-term cure. A value of ≤1.5 ng/ml at 6 h following surgery may predict long-term cure in two-thirds of the patients with acromegaly who undergo TSS.

TRENDS IN GROWTH HORMONE STIMULATION TESTING AND GROWTH HORMONE DOSING IN ADULT GROWTH HORMONE DEFICIENCY PATIENTS: RESULTS FROM THE ANSWER PROGRAM.

OBJECTIVE: Adult growth hormone deficiency (AGHD) results in physiologic impairments that may reduce quality of life and negatively impact body composition. AGHD can be treated with recombinant human growth hormone (GH). This study analyzes AGHD patients enrolled in the American Norditropin(®) STUDIES: Web-Enabled-Research (ANSWER) Program/NovoNet, a U.S. observational noninterventional study of patients treated with Norditropin(®) (somatropin [recombinant DNA origin] injection) at the discretion of their physicians. METHODS: Data were evaluated for GH stimulation test (GHST) usage and Norditropin(®) doses over 4 years. RESULTS: Adults (N = 468) with isolated GHD (IGHD) or multiple pituitary hormone deficiency (MPHD) were evaluated. The most commonly used GHSTs were arginine + L-dopa (27%; mostly a single center) and glucagon (25%; most frequent test after 2009). The percent of patients meeting recommended test-specific cut points varied from 32 to 100%, depending on the GHST used. Mean baseline GH doses were higher for MPHD patients and for younger patients in both IGHD and MPHD groups. CONCLUSION: MPHD was more common than IGHD. Mean GH doses were higher in younger patients, consistent with a transition from higher pediatric to lower adult dosing. Over time, glucagon became the most popular GHST. The use, in some patients, of other GHSTs with cut points, as well as starting doses not consistent with current recommendations, highlights the need for continued education regarding treatment guidelines for AGHD.

Cytoplasmic expression of SSTR2 and 5 by immunohistochemistry and by RT/PCR is not associated with the pharmacological response to octreotide.

OBJECTIVE: To evaluate expression of somatostatin receptor subtypes 2 and 5 (SSTR 2 and 5) by RT/PCR and immunohistochemistry (IHC) in GH-secreting adenomas, seeking correlations with response to octreotide. METHODS: SSTR2 and 5 expression was tested by IHC (n=37), RT/PCR (n=36) or both (n=13) in GH-secreting adenomas from 60 patients with acromegaly who had undergone pituitary surgery; 36 had been treated preoperatively with octreotide LAR for 3-6 months, and were categorized as responders (achievement of GH <2.5ng/mL and a normal age-adjusted IGF-1), partial responders (GH and IGF-1 reduction >50% and >30%, respectively) or non-responders. IHC was performed on a tissue microarray using specific antibodies directed to the carboxyl terminus of SSTR2 and 5. RESULTS: SSTR5 was the predominantly expressed receptor subtype by both IHC and RT/PCR in all tumors tested, regardless of whether they came from octreotide-naïve, octreotide-responsive, or octreotide-resistant patients. Immunostaining was concentrated in the cytoplasm. Neither SSTR2 nor SSTR5 expression correlated with baseline or post-octreotide GH or IGF-1 levels or tumor volume by either method. The agreement rate between RT/PCR and IHC was 77% in all 13 adenomas in which both methods were used. CONCLUSION: Expression of these receptors does not guarantee an adequate response to somatostatin analogs; other functional aspects of this interaction, such as receptor homo- and heterodimerization, and the resulting signaling cascade, probably play a role in determining whether a patient will respond or not to these agents.

Detecting doping use: more than an analytical problem.

The recent Armstrong case, where more than 250 negative doping tests are confronted with the athlete's confession of erythropoietin use, blood doping, steroid, and growth hormone abuse, illustrates the limitations of current laboratory tests in detecting doping in sport. Despite numerous doping controls and simultaneous indications of common doping abuse among professional athletes in the last two decades, the number of positive urine tests for recombinant human erythropoietin (rHuEPO) remains remarkably low. Athletes are using various masking strategies, among them protease inhibitors, intravenous injections of rHuEPO and alternative erythropoiesis stimulating agents. As one of the countermeasures, the Athlete's Biological Passport has been introduced. The sensitivity of the Athlete's Biological Passport is limited if the effect of a low-dose doping remains within the intra-individual reference range. A possible solution could be the use of a novel Epo test (MAIIA Diagnostics). Another performance-enhancing strategy is the return to 'old' doping techniques, such as autologous blood transfusions. Several indirect methods to detect autologous blood transfusions have been proposed with the majority relying on changes in erythropoiesis-sensitive blood markers. Currently, an algorithm based on the haemoglobin (Hb) level concentration and the percentage of reticulocytes (OFF-hr model; Hb(g/l)-60·âˆš%ret) is approved by the World Anti-Doping Agency. Genetic factors have been identified which may interfere with test interpretation. A large inter- and intra-ethnic variation in testosterone glucuronidation and excretion has been described. Consideration of genetic variation should improve performance of the testosterone doping test. Taking into account the pre-analytical care and better tailoring of the threshold values could increase test sensitivity. Anti-doping laboratories should routinely adjust for multiple testing as failure of doping control to detect cheaters could lead to more frequent controls. Finally, despite the huge technological progress, there is a need for increased collaboration between physiologists, analytical chemists, biostatisticians, and ethicists to reduce doping in sport.

[Study on the height and weight in children with obstructive sleep apnea hypopnea syndrome].

OBJECTIVE: To investigate the influence of obstructive sleep apnea hypopnea syndrome (OSAHS) on children's growth. METHOD: Fifty-three children diagnosed as OSAHS were included in the treatment group and underwent tonsillectomy or adenoidectomy, and 51 normal children were employed as the control group. Main data monitored by PSG and growth hormone (GH) in children of the treatment group were recorded before and after surgery, in addition, growth hormone, height and weight of children in the treatment group and control group were respectively recorded and compared. RESULT: Height and weight of children with OSAHS before treatment were lower than that of the normal children and the difference was significant (P<0.05). Compared with the data before surgery, oxygen saturation of blood in children of treatment group recorded by PSG increased (P<0.05), while value of other data decreased (P<0.05). Growth hormone in children of the treatment group was lower than that of the control group and the difference between two group was significant (P<0.05), while the content of growth hormone in children of the treatment group elevated after 3 months postoperatively and at this time no difference was found between the two groups. CONCLUSION: Children with OSAHS present the symptom of upper airway obstruction, which badly affects sleep quality and results in decreased secretion of growth hormone and finally the height and weight of children is got involved. Timely surgery is necessary to alleviate the symptom.

Visceral adiposity index is associated with insulin sensitivity and adipocytokine levels in newly diagnosed acromegalic patients.

CONTEXT: The visceral adiposity index (VAI) has proved to be a marker of visceral adipose dysfunction, strongly associated with insulin sensitivity in both the general and specific populations of patients at metabolic risk. OBJECTIVE: The objective of the study was to test VAI as a useful tool to assess early metabolic risk in acromegaly. PATIENTS: Twenty-four newly diagnosed acromegalic patients (11 women and 13 men, aged 54.9 ± 13.6 yr) were grouped into those with normal (group A, n = 13, 54.2%) and those with high VAI (group B, n = 11, 45.8%). OUTCOME MEASURES: Glucose, hemoglobin A1c, nadir and area under the curve (AUC) of GH (AUC(GH)) during the oral glucose tolerance test, AUC(Cpeptide) during a mixed-meal tolerance test, M value during euglycemic-hyperinsulinemic clamp, oral dispositional index (DIo), each component of the metabolic syndrome, leptin, adiponectin, TNF-α, and IL-6. RESULTS: The VAI value was positively correlated with the age of patients (ρ = 0.408; P = 0.048), tumor volume (ρ = 0.638; P = 0.001), basal GH (ρ = 0.622; P = 0.001), nadir GH (ρ = 0.534; P = 0.007), AUC(GH) (ρ = 0.603; P = 0.002), IGF-I (ρ = 0.618; P = 0.001), TNF-α (ρ = 0.512; P = 0.010), and AUC(Cpeptide) (ρ = 0.715; p<0.001) and negatively with adiponectin (ρ = -0.766; P < 0.001), M value (ρ = -0.818; P < 0.001), and DIo (ρ = -0.512; P = 0.011). Patients with high VAI showed significantly higher basal GH levels (P = 0.018), AUC(GH) (P = 0.047), IGF-I (P = 0.047), AUC(Cpeptide) (P = 0.018), lower M value (P < 0.001), DIo (P = 0.006), and adiponectin levels (P < 0.001), despite the absence of a significantly higher prevalence in the overt metabolic syndrome and glucose tolerance abnormalities. AUC(GH) proved to be the main independent factor influencing VAI. CONCLUSIONS: In acromegaly, VAI appears to be associated with disease activity, adiponectin levels, and insulin sensitivity and secretion and is influenced independently by GH levels. VAI could therefore be used as an easy and useful new tool in daily clinical practice for the assessment of early metabolic risk associated with active acromegaly.

Predictors of morbidity and mortality in acromegaly: an Italian survey.

OBJECTIVE: To describe demographic and hormonal characteristics, comorbidities (diabetes mellitus and hypertension), therapeutic procedures and their effectiveness, as well as predictors of morbidity and mortality in a nationwide survey of Italian acromegalic patients. DESIGN: Retrospective multicenter epidemiological study endorsed by the Italian Society of Endocrinology and performed in 24 tertiary referral Italian centers. The mean follow-up time was 120 months. RESULTS: A total of 1512 patients, 41% male, mean age: 45±13 years, mean GH: 31±37 µg/l, IGF1: 744±318 ng/ml, were included. Diabetes mellitus was reported in 16% of cases and hypertension in 33%. Older age and higher IGF1 levels at diagnosis were significant predictors of diabetes and hypertension. At the last follow-up, 65% of patients had a controlled disease, of whom 55% were off medical therapy. Observed deaths were 61, with a standardized mortality ratio of 1.13 95% (confidence interval (CI): 0.87-1.46). Mortality was significantly higher in the patients with persistently active disease (1.93; 95% CI: 1.34-2.70). Main causes of death were vascular diseases and malignancies with similar prevalence. A multivariate analysis showed that older age, higher GH at the last follow-up, higher IGF1 levels at diagnosis, malignancy, and radiotherapy were independent predictors of mortality. CONCLUSIONS: Pretreatment IGF1 levels are important predictors of morbidity and mortality in acromegaly. The full hormonal control of the disease, nowadays reached in the majority of patients with modern management, reduces greatly the disease-related mortality.

Somatic GNAS mutation causes widespread and diffuse pituitary disease in acromegalic patients with McCune-Albright syndrome.

CONTEXT: McCune-Albright syndrome (MAS) is caused by sporadic mutations of the GNAS. Patients exhibit features of acromegaly. In most patients, GH-secreting pituitary adenomas have been held responsible for this presentation. However, surgical adenomectomy rarely eliminates excess GH production. OBJECTIVE: The aim of this study was to elucidate pituitary pathology in patients with MAS and to explain the basis of failure of adenomectomy to eliminate GH hypersecretion. DESIGN AND SETTING: We conducted a case series at the National Institutes of Health. INTERVENTION(S): Interventions included medical therapy and transsphenoidal surgery. PATIENTS AND MAIN OUTCOME MEASURES: We studied clinical and imaging features and the histology and molecular features of the pituitary of four acromegalic MAS patients. RESULTS: We identified widespread and diffuse pituitary gland disease. The primary pathological changes were characterized by hyperplastic and neoplastic change, associated with overrepresentation of somatotroph cells in structurally intact tissue areas. Genetic analysis of multiple microdissected samples of any type of histological area consistently revealed identical GNAS mutations in individual patients. The only patient with remission after surgery received complete hypophysectomy in addition to removal of multiple GH-secreting tumors. CONCLUSIONS: These findings indicate developmental effects of GNAS mutation on the entire anterior pituitary gland. The pituitary of individual cases contains a spectrum of changes with regions of normal appearing gland, hyperplasia, and areas of fully developed adenoma formation, as well as transitional stages between these entities. The primary change underlying acromegaly in MAS patients is somatotroph hyperplasia involving the entire pituitary gland, with or without development of somatotroph adenoma. Thus, successful clinical management, whether it is medical, surgical, or via irradiation, must target the entire pituitary, not just the adenomas evident on imaging.

Label-free differentiation of human pituitary adenomas by FT-IR spectroscopic imaging.

Fourier transform infrared (FT-IR) spectroscopic imaging has been used to characterize different types of pituitary gland tumors and normal pituitary tissue. Freshly resected tumor tissue from surgery was prepared as thin cryosections and examined by FT-IR spectroscopic imaging. Tissue types were discriminated via k-means cluster analysis and a supervised classification algorithm based on linear discriminant analysis. Spectral classification allowed us to discriminate between tumor and non-tumor cells, as well as between tumor cells that produce human growth hormone (hGH+) and tumor cells that do not produce that hormone (hGH-). The spectral classification was compared and contrasted with a histological PAS and orange G stained image. It was further shown that hGH+ pituitary tumor cells show stronger amide bands than tumor cells that do not produce hGH. This study demonstrates that FT-IR spectroscopic imaging can not only potentially serve as a fast and objective approach for discriminating pituitary gland tumors from normal tissue, but that it can also detect hGH-producing tumor cells.