[Acromegaly]

Pituitary MRI Features in Acromegaly Resulting From Ectopic GHRH Secretion From a Neuroendocrine Tumor: Analysis of 30 Cases

CONTEXT

Ectopic acromegaly is a consequence of rare neuroendocrine tumors (NETs) that secrete GHRH. This abnormal GHRH secretion drives GH and IGF-1 excess, with a clinical presentation similar to classical pituitary acromegaly. Identifying the underlying cause for the GH hypersecretion in the setting of ectopic GHRH excess is, however, essential for proper management both of acromegaly and the NET. Owing to the rarity of NETs, the imaging characteristics of the pituitary in ectopic acromegaly have not been analyzed in depth in a large series.

OBJECTIVE

Characterize pituitary magnetic resonance imaging (MRI) features at baseline and after NET treatment in patients with ectopic acromegaly.

DESIGN

Multicenter, international, retrospective.

SETTING

Tertiary referral pituitary centers.

PATIENTS

Thirty ectopic acromegaly patients having GHRH hypersecretion.

INTERVENTION

None.

MAIN OUTCOME MEASURE

MRI characteristics of pituitary gland, particularly T2-weighted signal.

RESULTS

In 30 patients with ectopic GHRH-induced acromegaly, we found that most patients had hyperplastic pituitaries. Hyperplasia was usually moderate but was occasionally subtle, with only small volume increases compared with normal ranges for age and sex. T2-weighted signal was hypointense in most patients, especially in those with hyperplastic pituitaries. After treatment of the NET, pituitary size diminished and T2-weighted signal tended to normalize.

CONCLUSIONS

This comprehensive study of pituitary MRI characteristics in ectopic acromegaly underlines the utility of performing T2-weighted sequences in the MRI evaluation of patients with acromegaly as an additional tool that can help to establish the correct diagnosis.

Prevalence and outcome of comorbidities associated with acromegaly

BACKGROUND

Acromegaly is associated with various comorbidities, such as arterial hypertension (aHT), type 2 diabetes mellitus (DM2), obstructive sleep apnoea syndrome (OSAS), carpal tunnel syndrome (CTS) and polyposis coli. For therapeutic decisions, it is essential to know if, and to what extent, these associated morbidities are reversible or preventable. The aim of this study is to assess the prevalence and course of aHT, obesity, OSAS, CTS, DM2 and polyposis coli in acromegalic patients.

METHODS

The following criteria for inclusion in this database study were used: treatment for acromegaly at the authors' institutions; full endocrinological and radiological work- and follow-up; screening for aHT, DM2, CTS, OSAS, obesity and polyposis coli. All patients were followed-up for > 3 months, and treatments were indicated with the intent of biochemical remission (normal IGF-1 and random growth hormone level).

RESULTS

Sixty-three patients were included. Twelve (19%), 45 (71%) and 6 (10%) patients harboured micro-, macro- and giant adenomas, respectively. Nineteen tumours (30%) invaded the cavernous sinus. Mean tumour volume was 5.4 cm³. Mean follow-up time was 42 months. Sixty-one (97%) patients had transsphenoidal surgery; two patients only had drug therapy. Surgery led to remission in 31 (51%) patients. Intracavernous growth and larger tumour volume were negative predictors for cure. Drug therapy lead to remission in 22 (73%) patients within a mean follow-up of 54 months. The pretherapeutic prevalence of associated morbidities was as follows: aHT, 56%; DM2, 25%; OSAS, 29%; CTS, 29%; polyposis coli, 5%. There were neither age nor gender preferences for the respective prevalences. Surgery leads to remission of aHT and DM2 in 6% and 25%, respectively. Additional drug therapy resulted in remission of aHT, DM2 and CTS in 17%, 14% and 14%, respectively. Other associated morbidities persisted regardless of therapeutic efforts. Even if criteria for remission were not met, no new comorbidities of acromegaly developed during follow-up.

CONCLUSIONS

Treating acromegaly may relieve threatening associated morbidities such as aHT and DM2; nevertheless, only few comorbidities are reversible, which highlights the importance of treating acromegaly as early as possible.

Acromegaly is associated with vertebral deformations but not vertebral fractures: Results of a cross-sectional monocentric study

OBJECTIVES

Patients with acromegaly appear to be at increased risk of vertebral fractures despite normal bone mineral density. We investigated the prevalence of vertebral fractures in a cohort of acromegalic patients under 80 years of age.

METHODS

Monocentric cross-sectional study performed at Nantes University Hospital from 1988 to 2018. Fifty patients (18 females, 32 males) with a median age of 52.3 years (range: 27-78) were included. Radiological vertebral fractures were evaluated on conventional lumbar and thoracic spine radiographs using Genant's semiquantitative fracture assessment. We studied qualitative abnormalities of the spine using three criteria: osteophytes, disc-space narrowing and wedge-shaped vertebrae. We analysed bone mineral density and endocrine status.

RESULTS

Three patients (6%) had a vertebral fracture: one grade 1 and two grade 2 according to Genant's assessment, with two osteoporotic and one osteopenic patients. They had no unsubstituted pituitary deficiency. Considering the frank deformations (osteophyte or disc narrowing≥grade 2 or wedge-shaped), the thoracic spine was deformed in 22 patients (44%) and the lumbar spine in 21 patients (42%).

CONCLUSION

Acromegalic patients had a low prevalence of vertebral fractures but had a significant amount of vertebral deformations. We speculate that this high prevalence of frank deformations could explain the previously reported high prevalence of vertebral fractures.

Daily life reflections of acromegaly guidelines

PURPOSE

To determine the differences in acromegaly diagnosis, treatment, and follow-up among Turkish endocrinologists, and to investigate how the published guidelines are applied in clinical practice.

METHODS

The questionnaire was formatted as an electronic survey, conducted between November and December 2015, and sent weekly for 6 weeks via e-mail to 528 endocrinologists in Turkey.

RESULTS

The questionnaire was answered by 37.4 % of endocrinologists. Insulin-like growth factor-1 and nadir growth hormone level after 75 g oral glucose tolerance test (nadir GH-OGTT) were the most commonly preferred methods for the initial diagnosis. A total of 49.5 % of the participants reported using preoperative medical therapy (MT) either routinely or on a case-to-case basis. Somatostatin analogs were the most commonly used drugs, both in pre- and postoperative MT. Disease activity following surgery was assessed in the 3rd postoperative month using IGF-1 levels. Similarly, IGF-1 monitoring was preferred in the follow-up period. Monitoring nadir GH-OGTT levels was the most commonly used method in the assessment of discordant test results. The dose titration was done at month 3 after the start of MT. Resistance to SRLs was considered after using the maximal dose for at least 6 months. Pegvisomant was generally used in second- and third-line therapy. Similarly, cabergoline was not preferred in monotherapy by the majority of participants. Radiotherapy was considered in patients with incomplete response to surgery and medical treatments.

CONCLUSIONS

Although there were subtle differences, clinical practice guidelines were usually followed among Turkish endocrinologists.

[Bestiaries in clinical dermatology]

Metaphors have always played a role in the medical tradition and in dermatology too. Beyond their initially playful aspect, metaphors offer a way of rapidly identifying a lesion and of linking it to one or more diseases. They also play a role in the education of medical students and residents by making it easier to memorise different diseases. Herein we discuss "animal" metaphors.

[Hand and endocrine diseases]

The whole of hormones likely influence state of hands, modifying colouring and trophicity of the skin and having influence on its muscular, tendineous, osseous, articular components. Thus state of the hands contributes to the recognition of the endocrine diseases: hot and moist hands of the Graves' disease, dry, cold and infiltrated hands in myxoedema, pale and fine hands of hypopituitarism, broad and thick hand of acromegaly, brachymetacarpia in the pseudohypoparathyroidism… Diabetes exposes particularly to tendineous and articular retractions, to whitlows and ungual mycosis.

Familial isolated pituitary adenomas: an emerging clinical entity

Familial pituitary tumors are increasingly recognized. While some of these cases are related to wellknown syndromic conditions such as multiple endocrine neoplasia type 1 (MEN1) or Carney complex, others belong to the familial isolated pituitary adenoma (FIPA) patient group. The discovery of heterozygous, loss-of-function germline mutations in the gene encoding the aryl hydrocarbon receptor interacting protein (AIP) in 2006 has subsequently enabled the identification of a mutation in this gene in 20% of FIPA families and 20% of childhood-onset simplex soma- totroph adenomas. The exact mechanism by which the lack of AIP leads to pituitary adenomas is not clear. AIP mutations cause a low penetrance autosomal dominant disease with often a distinct phenotype characterized by young-onset, aggressive, large GH, mixed GH and PRL or PRL-secreting adenomas. This review aims to summarize currently available clinical data on AIP mutation-positive and negative FIPA patients.

Acromegaly without acral changes: A rare presentation

Acromegaly is diagnosed clinically by the universal presence of acral enlargement and typical coarse facies. We report a short, elderly female developing acromegalic facies for last 10 years without acral overgrowth. She is a patient of primary hypothyroidism, well controlled for last 20 years. Acromegaly was proven by high level of serum insulin like growth factor-1 (IGF-1) and elevated and nonsuppressed level of growth hormone (GH), with other hormonal profile being undisturbed. She had mild insulin resistance and systemic hypertension in absence of any visual field defect. Magnetic resonance imaging (MRI) of brain revealed pituitary hyperplasia without any detectable adenoma. No source of ectopic secretion of GH or growth hormone releasing hormone (GHRH) could be localized. Therefore, atypical presentation of acromegaly needs high degree of suspicion even if some of the common features are lacking. Here, we have biochemically proved acromegaly with typical facies, short stature but no acral overgrowth and pituitary adenoma despite longstanding disease activity, and thus eluding diagnosis for years.

[Characteristics of sleep apnea syndrome in a cohort of patients with acromegaly]

INTRODUCTION

Sleep apnoea syndrome (SAS) has a prevalence of between 40 and 80 % in patients with acromegaly. The objective of our study was to focus on the occurrence of SAS and its relation with acromegalic characteristics in this population as well as to study patients' comorbidities.

METHODOLOGY

This study was retrospective, monocentric and related to a cohort of 106 acromegalic patients of whom 55 patients had performed ventilatory polygraphic recordings looking for SAS in addition to assessment of comorbidities.

RESULTS

Within the screened patients, 42 had sleep apnoea syndrome with a majority of them having severe SAS. In this population, SAS was associated with hypertension, diabetes and a longer duration of acromegaly but acromegaly control was not a risk factor. Patients with severe SAS were older (mean 64 years) than the ones without SAS (47 years) (P=0.01).

CONCLUSION

SAS prevalence is twenty times higher in the acromegalic population than for the normal population, even more so if patients are diabetic, hypertensive, older and if acromegaly has had a long evolution. Knowing this high prevalence, systematic screening for SAS may be justified in this population.

Which patients with acromegaly are treated with pegvisomant? An overview of methodology and baseline data in ACROSTUDY

Context Pegvisomant (Somavert, Pfizer Inc.) is the first and only available GH receptor antagonist. ACROSTUDY is an international surveillance study that offers inclusion in a web-based registry to all patients with acromegaly treated with pegvisomant; it aims at monitoring long-term safety and efficacy of this compound. Patients and methods This report summarizes the main baseline characteristics of this particular population of patients. In February 2009, over 300 centres in 10 countries had contributed 792 patients. A gradual increase in cumulative patient recruitment was observed since the launching of ACROSTUDY in 2004: from 116 patients in 2005, it steeply increased to 792 at the latest data freeze in February 2009. At the time of enrolment, 91.8% of patients were already treated with pegvisomant but baseline was considered at the time of pegvisomant start. IGF1 concentrations were measured at local laboratories. Results Of all patients, 80% were reported to have had surgery and 33% to have received radiation therapy. Of the 792 patients, 14% had received no prior medical treatment before pegvisomant start, 65.9% had received somatostatin analogues and 18.6% dopamine agonists. Interestingly, 66.7% had received only pegvisomant at study start, while it was taken in association with dopamine agonists in 5.7%, with somatostatin analogues in 23.4% and with both types of agents in 3.8%. Mean IGF1 at baseline was 522 ng/ml. Conclusion Analysis of the baseline features of these patients treated with pegvisomant and reported in the ACROSTUDY database underscores the severity of the disease in this subset of the population of patients with acromegaly previously unresponsive to several medical, surgical or radiation treatment approaches.