Pituitary carcinomas

Pituitary carcinoma is a extremely rare and is characterized by a very poor prognosis. Even if at diagnosis the presence of metastases is required to define a pituitary carcinoma, the lesion was almost invariably diagnosed first as a benign pituitary tumor, that after a variable period of latency, ranging from few months to many years, changed its natural course to an aggressive pituitary tumor poorly responsive to therapy. Recent studies have partially clarified its molecular pathogenesis and found possible markers of aggressiveness in order to make an earlier diagnosis, when still treatment could improve their prognosis. Most pituitary carcinomas are functioning, and ACTH- and PRL-secreting carcinomas are the most frequent. Treatment includes surgery, radiotherapy, medical therapy and chemotherapy, but the poor results with current therapies should prompt all investigators to better understand its pathogenesis and searching new molecular targets for treatments.

A heritable predisposition to pituitary tumors

Pituitary tumors are prevalent in the general population, with a frequency of nearly 1 in 5. The cause of most pituitary tumors remains unknown, although a genetic contribution is recognized for some. We analyzed the Utah Population Data Base (UPDB), a resource combining a computerized genealogy of the Utah population with a statewide tumor registry, to investigate familial clustering of pituitary tumors. We analyzed the genetic relationships among 741 individuals diagnosed with benign or malignant pituitary tumors who had Utah genealogy data. To test for evidence of genetic contribution to predisposition, we compared average relatedness between all pairs of individuals with pituitary tumors with the expected relatedness in this population. We also estimated relative risks (RRs) for pituitary tumors in close and distant relatives of cases by comparing observed and expected numbers of cases among relatives. Relative risks for first- and third-degree relatives were significantly elevated (RR = 2.83 and 1.63, respectively), while relative risk for second-degree relatives was not significantly different from 1.0 (RR = 0.83). The average pairwise relatedness of pituitary tumor cases was significantly higher than expected, even when close relationships were ignored. The significantly elevated risks to relatives as well as the significant excess distant relatedness observed in cases provide strong support for a genetic contribution to predisposition to pituitary tumors. Multiple high-risk pedigrees can be identified in the UPDB, and study of such pedigrees might allow identification of the gene(s) responsible for our observations. Recognizing genetic contribution to the disease may also help with counseling family members of affected individuals.

Prevalence of double pituitary adenomas in a surgical series: Clinical, histological and genetic features

BACKGROUND

The term double pituitary adenomas (DPA) is usually referred to those rare lesions showing two distinct cellular components. Genetic background may sustain the proliferation of more than one cell at the same time but no information is available on the presence of aip mutations in these patients.

AIM

We report the prevalence and the endocrinological, neuroradiological, histopathological and genetic features of DPA detected in a large surgical series. The contribution of pituitary transcription factor immunostains in DPA was also evaluated.

SUBJECTS AND METHODS

One-hundred-forty-four patients undergoing surgery for tumors of the sellar region were evaluated. Histopathology, immunohistochemistry and the mutational analysis for the entire coding region of the AIP and MEN1 genes were performed.

RESULTS

One-hundred-seventeen patients out of 144 had a pituitary adenoma. DPA was found in 3 (2.6%) out of 117 patients with pituitary adenoma. Immunohistochemistry and transcription factors analysis demonstrated two not yet described histotype associations in DPA. The coexistence of somatotroph-lactotroph and silent mammosomatotroph histotype in 1 case and the coexistence of sparsely granulated lactotroph and null cell adenomas in the remaining two cases were first identified. Sequencing data for the coding region of the aip and the menin gene resulted in wild type sequences in all patients with DPA.

CONCLUSIONS

The prevalence of DPA observed in our unselected surgical series is not negligible (2.6%). Furthermore, the evaluation of the treatment outcome would suggest that the clinical management of DPAs requires a careful diagnostic approach and follow- up.

Prevalence of pituitary adenomas: a community-based, cross-sectional study in Banbury (Oxfordshire, UK)

BACKGROUND

Pituitary adenomas (PAs) are associated with increased morbidity and mortality. The optimal delivery of services and the provision of care for patients with PAs require distribution of the resources proportionate to the impact of these conditions on the community. Currently, the resource allocation for PAs in the health care system is lacking a reliable and an up-to-date epidemiological background that would reflect the recent advances in the diagnostic technologies, leading to the earlier recognition of these tumours.

OBJECTIVES

To determine the prevalence, the diagnostic delay and the characteristics of patients with PA in a well-defined geographical area of the UK (Banbury, Oxfordshire).

PATIENTS AND METHODS

Sixteen general practitioner (GP) surgeries covering the area of Banbury and a total population of 89 334 inhabitants were asked to participate in the study (data confirmed on 31 July 2006). Fourteen surgeries with a total of 81,449 inhabitants (91% of the study population) agreed to take part. All cases of PAs were found following an exhaustive computer database search of agreed terms by the staff of each Practice and data on age, gender, presenting manifestations and their duration, imaging features at diagnosis, history of multiple endocrine neoplasia type 1 and family history of PA were collected.

RESULTS

A total of 63 patients with PA were identified amongst the study population of 81,149, with a prevalence of 77.6 PA cases/100,000 inhabitants (prolactinomas; PRLoma: 44.4, nonfunctioning PAs: 22.2, acromegaly; ACRO: 8.6, corticotroph adenoma: 1.2 and unknown functional status; UFS: 1.2/100,000 inhabitants). The distribution of each PA subtype was for PRLoma 57%, nonfunctioning PAs 28%, ACRO 11%, corticotroph adenoma 2% and UFS 2%. The median age at diagnosis and the duration of symptoms until diagnosis (in years) were for PRLoma 32.0 and 1.5, nonfunctioning PAs 51.5 and 0.8, ACRO 47 and 4.5 and corticotroph adenoma 57 and 7, respectively. PRLoma was the most frequent PA diagnosed up to the age of 60 years (0-20 years: 75% and 20-60 years: 61% of PAs) and nonfunctioning PA after the age of 60 years (60% of PAs). Nonfunctioning PAs dominated in men (57% of all men with PA) and PRLoma in women (76% of all women with PA). Five patients (7.9%) presented with classical pituitary apoplexy, with a prevalence of 6.2 cases/100,000 inhabitants.

CONCLUSIONS

Based on a well-defined population in Banbury (Oxfordshire, UK), we have shown that PAs have a fourfold increased prevalence than previously thought; our data confirm that PAs have a higher burden on the Health Care System and optimal resource distribution for both clinical care and research activities aiming to improve the outcome of these patients are needed.

The prevalence of benign and malignant neoplasms in acromegalic patients

INTRODUCTION

In acromegalic patients, the prevalence of certain benign and malignant neoplasms is higher than that in the healthy population. We retrospectively evaluated the prevalence of tumours in acromegalic patients treated at our department: the regional centre for acromegalic patients for the Małopolskie voivodeship in Poland.

MATERIAL AND METHODS

During the years 1983-2008, a hundred and one acromegalic patients (30 males and 71 women), of mean age 51.8 +/- 15.4 years, were diagnosed and treated. Pituitary macroadenoma and microadenoma were stated in 63.4% and 25.7% of these patients, respectively. In 10.9% of these patients no data on tumour diameter were available. The mean observation period was 9.4 +/- 6.5 years. The median levels of hGH and IGF-1 prior to neurosurgery were 20.2 (IQR = 34.9) ng/ml and 764.5 (IQR = 569.6) ng/ml, respectively.

RESULTS

In the studied group of patients, we found the following prevalence of various tumours: nodular goitre - 64/101 patients (63.0%), polyps of the colon - 13/101 patients (13.0%); uterine polyps - 4/101 patients (4.0%); and prostate adenoma - 2/101 patients (2.0%). Among malignant tumours, thyroid cancer, endometrium and cervix cancer were the most frequent, each of these occurring in 3 patients (3.0%). Colon cancer prevalence was 2.0% (in 2 patients).

CONCLUSIONS

From our retrospective study, we suggest an overall increase of tumour incidence in acromegalic patients. Prospective multicentre studies are required to resolve the significance of this observation. In our study group, the number of malignant neoplasms was significantly higher in patients with long-lasting uncontrolled disease (over 5 years), compared to patients with controlled disease. (Pol J Endocrinol 2010; 61 (1): 29-34).

Etiology, functional status and short term outcome of patients with pituitary lesions. An experience from a developing country

OBJECTIVE

To describe the etiology, functional status and short term outcome of patients with pituitary lesions (PL).

METHODS

Brain or pituitary MRI reports of 3753 patients were analyzed for PL over the period of 2000 to 2007, done at the Aga Khan University Hospital (AKUH), Karachi, Pakistan. MRIs with reported PL and all those ordered by Endocrinologists with or without pituitary abnormalities, were included in the analysis. This made a total of 338 (9%) MRI reports. PL were defined as pituitary tumors, cysts, haemorrhage, hypoplasia; and empty sella. Patients with these PL, were analyzed for symptoms, hormonal profile and short term outcome in the hospital retrospectively.

RESULTS

In the analysis of 338 MRI reports, 23% had normal pituitary gland on MRI examination. Hypogonadotrophic hypogonadism was the commonest (38.5%) endocrine abnormality seen with normal pituitary MRI, followed by hypopituitarism (5.1%). Most common PL identified were macroadenoma (38.7%), empty sella (16.5%) and microadenoma (12.7%). Patients with macroadenoma had 58% of non-functional tumours while 19.1% had hypopituitrism, 17.6% had acromegaly and 17.5% had prolactinoma. Majority of these lesions were causing headache and visual symptoms (42.7%) and were treated with surgery (75.5%). Patients with microadenoma included 39.5% prolactinomas, 18.6% cushing disease, 14% acromegaly, 4.7% hypogonadotrophic hypogonadism and 2.3% hypopituitrism. Majority of these lesions were treated with drugs and 37.3% were treated with surgery. In empty sella patients, 32% patients had endocrine abnormalities among which 21.4% had hypopituitrism, 2% had hypogonadotrophic hypogonadism, and only 6% patients had normal endocrine workup. A significant number of patients (62.5%) never had endocrine hormonal checkup.

CONCLUSION

Although PL are less common entities (9% in 3,753 reports) but they are associated with significant endocrinal abnormalities and need prompt treatment. Empty sella, which is not considered as a distinct abnormality, is also associated with significant endocrine deficiencies.

[Epidemiology of pituitary adenoma: results of the first Swiss study]

Epidemiological data concerning pituitary adenomas are very scarce and in some cases reports are even conflicting. This opinion is at present disputed. The aim of this study was, therefore, to evaluate in the urban area of Fribourg, the prevalence of relevant clinical pituitary adenoma. General practitioners, endocrinologists and gynaecologists were questioned concerning any patient within this agglomeration presenting with a pituitary micro- or macro-adenoma. Among the 44 adenomas, we observed 13 non secreting macro-adenomas, 16 micro- and 9 macro-prolactinomas, 4 cases of acromegaly and 2 ACTH-dependant Cushing diseases. In the studied area we found a prevalence of 80.5 pituitary adenomas per 100,000, or 1 case per 1241 corroborating a greater prevalence of pituitary adenomas than previously believed.

[Genetics of familial pituitary adenomas]

Pituitary adenomas were previously thought to be rare. However, a recent cross-sectional study conducted in Liège, Belgium, showed that clinically apparent pituitary adenomas were present in about 1 in 1000 inhabitants, which is 4 to 5 times the previously reported prevalence. Pituitary adenomas are generally sporadic, but some are associated with familial-isolated tumoral syndromes (mainly MEN1 and Carney complex). With the recent characterization of FIPA (Familial Isolated Pituitary Adenomas), familial pituitary adenomas are now thought to account for 5% to 8% of all pituitary tumors. New genetic mechanisms are being identified, improving our understanding of the complex manifestations and sometimes unpredictable outcome of pituitary adenomas.

Pituitary tumours: pituitary incidentalomas

Clinically non-functioning pituitary adenomas range from being completely asymptomatic, and therefore being detected either at autopsy or as incidental findings on head magnetic resonance imaging (MRI) or computed tomography (CT) scans performed for other reasons (often referred to as 'pituitary incidentalomas'), to causing significant hypothalamic/pituitary dysfunction and visual field compromise due to their large size. Patients with pituitary incidentalomas should all be screened for hypersecretion (prolactin (PRL), IGF-1, midnight salivary cortisol), and those with macroadenomas should also be screened for hypopituitarism (macroadenomas) and for visual field defects if the tumour abuts the optic chiasm. Growth of non-functioning pituitary adenomas without treatment occurs in about 10% of microadenomas and 24% of macroadenomas. In the absence of hypersecretion, hypopituitarism or visual field defects, patients may be followed up by periodic screening by MRI for enlargement. Growth of a pituitary incidentaloma is an indication for surgery.

The epidemiology and genetics of pituitary adenomas

According to data derived from autopsy and radiological imaging series, pituitary tumours occur very commonly in the general population; however, most of these tumours are incidental findings with no obvious clinical impact. The historical data on the prevalence of pituitary adenomas in the clinical setting are scant and point to such tumours being relatively rare. Recent studies have shown that the prevalence of clinically relevant pituitary adenomas is 3-5 times higher than previously reported, which adds impetus to research into the aetiology of these tumours. Although the majority of pituitary adenomas are sporadic, approximately 5% of all cases occur in a familial setting and over half of these are due to Multiple Endocrine Neoplasia Type 1 (MEN-1) and Carney's Complex (CNC) disorders. Since the late 1990 s, we have described non-MEN1/CNC familial pituitary tumours that include all tumour phenotypes as a condition termed Familial Isolated Pituitary Adenomas (FIPAs). The clinical characteristics of the FIPAs vary from those sporadic pituitary adenomas, as patients with FIPAs have a younger age at diagnosis and larger tumours. About 15% of the FIPA patients have mutations in the aryl hydrocarbon receptor-interacting protein gene (AIP), which indicates that the FIPA may have a diverse genetic pathophysiology.

[Endoscopic treatment of pituitary adenomas]

The endoscopic approach is increasingly used for surgical treatment of pituitary adenomas. Early outcome is generally excellent, especially in experienced hands, and particularly for non invasive tumors. Treatment of these patients requires multidisciplinary collaboration among endocrinologists, radiologists and neurosurgeons.

Non-adenomatous pituitary tumours

Apart from pituitary adenomas, a number of tumours may arise from within the sella presenting a diagnostic and therapeutic challenge at a multidisciplinary specialist level. This article focus on the most commonly diagnosed non-adenomatous pituitary tumours (craniopharyngiomas, Rathke's cleft cysts and meningiomas) and provides data on their pathogenesis, diagnosis and treatment.

Pituitary tumours: the prolactinoma

This review focus on the epidemiology, diagnosis and treatment of prolactinomas. In particular, attention was given to recent data showing a high prevalence of these tumours in the general population, 3-5 times higher than previously reported. The diagnosis of hyperprolactinaemia has been simplified in recent years, and only prolactin (PRL) assay and magnetic resonance imaging of the sella are required. Nonetheless, macroprolactinaemia should be assessed in patients with hyperprolactinaemia in the absence of clinical symptoms of elevated PRL levels. The recent evidence that medical therapy with dopamine agonists should be continued lifelong has been confirmed by several studied. The patients achieving disappearance of the tumours and suppression of PRL levels during treatment are those showing the highest likelihood to have persistent remission of hyperprolactinaemia after treatment withdrawal.

Pituitary tumor size in acromegaly during pegvisomant treatment: experience from MR re-evaluations of the German Pegvisomant Observational Study

In treatment-resistant patients with acromegaly, pharmacotherapy with pegvisomant (Somavert) is a highly effective option. However, safety concerns have been raised related to a potential increase in tumor size during long-term pegvisomant treatment. Therefore, neuroradiological monitoring of tumor extension and volume was performed in the German Pegvisomant Observational Study, which covers 87% of patients treated with pegvisomant in Germany. As of 15 July 2007, a total of 307 patients (156 males and 151 females) had been included in the study and were on pegvisomant therapy for an average of 86.7 weeks. Median and mean doses of pegvisomant were 15 and 16.6 mg/day respectively. Out of these 307 patients, 18 were reported to have tumor-size increases as adverse events. From these 18 patients, all available serial magnetic resonance images were collected. Identical or similar sequences were chosen and the region of interest was magnified and compared across time after the best possible fit had been achieved by size and gray-scale correction. All available images were carefully re-evaluated according to this method. In 10 out of the 18 patients, there was no evidence of tumor-size increase, when the pre-treatment scans were compared with the most recent follow-up investigations. In two out of the remaining eight patients, there was a rebound effect observed after withdrawal of somatostatin analog treatment, but no further progression. In another three out of the eight patients, tumor-size increase had already been documented before pegvisomant treatment was commenced, during preceding somatostatin analog treatment and continued therapy. In the last three patients, tumor progression after the start of pegvisomant treatment was confirmed. All three patients had undergone pituitary surgery as primary treatment, but had not been pre-treated with radiotherapy. In all three cases, the tumor increase was not considered clinically significant and the investigators decided to continue pegvisomant treatment. In conclusion, in this large group of pegvisomant-treated patients, tumor progression was rare. It was reported in between 2 and 3% of patients treated, and did not exceed the expected rate in patients with acromegaly not treated with pegvisomant. In over one-half of patients, reports of tumor increase could not be confirmed by re-evaluation. This was mostly due to non-identical gantry projections. Misjudgements mainly occurred when only images from two individual investigations, rather than the entire series of scans, were compared. Thus, we recommend a careful serial evaluation of all available images to avoid misinterpretations and erroneous alerts. As from this presently largest database of acromegalic patients treated with pegvisomant, tumor-growth rate appears not to be different from patients on other treatment modalities. Although these data are reassuring with regard to the concern of somatotroph adenoma growth under peripheral GH receptor blockade, further study is required.

Prevalence of GH deficiency in cured acromegalic patients: impact of different previous treatments

OBJECTIVE

Radiotherapy (RT) for pituitary adenomas, including GH-secreting ones, frequently leads to GH deficiency (GHD). Data on the effects of surgery alone (S) on dynamic GH secretion are limited. The aim of the study was to investigate the occurrence of GHD in acromegalic patients treated with different therapeutic options.

DESIGN AND METHODS

Fifty-six patients in remission from acromegaly, (33 F & 23 M, age: 54+/-13 years, body mass index (BMI): 28.4+/-4.1 kg/m(2), 21 with adequately substituted pituitary deficiencies) treated by S alone (n=33, group 1) or followed by RT (n=23, group 2), were investigated for GHD by GHRH plus arginine testing, using BMI-adjusted cut-offs. Several metabolic and cardiovascular parameters (waist circumference, body fat percentage, blood pressure, fasting and post-oral glucose tolerance test glucose, HbA1c, insulin resistance and lipid profile) were evaluated in all the patients and 28 control subjects with known diagnosis of GHD.

RESULTS

Serum GH peak after challenge was 8.0+/-9.7 microg/l, without any correlation with post-glucose GH nadir and IGF-1 levels. The GH response indicated severe GHD in 34 patients (61%) and partial GHD in 15 patients (27%). IGF-1 were below the normal range in 14 patients (25%). The frequency of GHD was similar in the two treatment groups (54% in group 1 and 70% in group 2). No significant differences in metabolic parameters were observed between acromegalic patients and controls with GHD.

CONCLUSIONS

Severe GHD may occur in about 60% of patients treated for acromegaly, even when cured after S alone. Thus, a stimulation test (i.e. GHRH plus arginine) is recommended in all cured acromegalic patients, independently from previous treatment.

Personality in patients with pituitary adenomas is characterized by increased anxiety-related traits: comparison of 70 acromegalic patients with patients with non-functioning pituitary adenomas and age- and gender-matched controls

OBJECTIVE

Although neuropsychiatric and morphological brain alterations in acromegalic patients have been described and a distinct disease personality is clinically suspected, this has never been systematically investigated. We examined whether patients with acromegaly showed an altered personality profile compared with patients with non-functioning pituitary adenomas and healthy controls.

DESIGN AND METHODS

In this cross-sectional study, 70 acromegalic patients and 58 patients with non-functioning pituitary adenomas were compared with 140 mentally healthy population controls, matched for age and gender. Personality traits were measured by standardized personality questionnaires (Eysenck personality questionnaire-RK and tridimensional personality questionnaire).

RESULTS

Compared with healthy controls, acromegalic patients described themselves as distinctly more harm avoidant and neurotic and presented themselves with high social conformity. On harm avoidant subscales, they reported more anticipatory worries and pessimism, higher fear of uncertainty, higher fatigability and asthenia. This personality pattern was not specific for acromegaly, but could similarly be observed in patients with non-functioning pituitary adenomas. However, specific for patients with GH-producing adenomas was an even more reduced novelty-seeking behaviour, especially in terms of lower impulsiveness, compared with patients with non-functioning pituitary adenomas.

CONCLUSION

Patients with pituitary adenomas show a distinct pattern of increased anxiety-related personality traits compared with the general population, potentially as a result of the pituitary lesion and/or associated hormonal dysregulations and comorbidities. Acromegaly is additionally associated with reduced impulsivity and novelty-seeking behaviour, which might affect patients' management and their quality of life.

[Prolactinoma]

Prolactin-secreting tumours (prolactinomas) are benign neoplasms constituting about 40 percent of all pituitary tumours. The incidence of these tumours varies with age and sex, occurring most frequently in females between 20 and 40-years-old. The clinical symptoms of prolactinomas are menstrual dysfunction and galactorrhea in women and loss of libido and potency in men. Differential diagnosis of the disease should include the intake of various drugs, hypothyroidism, renal failure, liver cirrhosis, compression of the pituitary stalk by other pathologies, idiopathic hyperprolactinemia and other types of pituitary adenomas. The aims of treatment are to restore or to achieve eugonadism through the normalisation of hyperprolactinemia and control of tumour mass. Because of the established effectiveness in the majority of cases and small number of acceptable adverse effects, dopamine agonists are considered the drugs of choice. Transsphenoidal surgery remains an option when medical therapy is neither effective nor well tolerated. The authors review the diagnosis and management of prolactinomas, including progress made in recent years.

Pituitary incidentalomas--how often is too often?

INTRODUCTION

Clinical nonfunctional pituitary microadenomas, also known as incidentalomas are accidental observations made due to the application of high resolution imaging techniques as computed tomography or magnetic resonance. There are no standards regarding the follow-up of these tumors and taking into account their increased frequency among general population (during the last years they were based on the high performances of the imaging methods), we decided to study their dimensions and their evolution over time. We have also analysed their behavior with respect to their endocrine phenotype and the minimum period of time needed for the repetition of the imagistic procedure.

AIM

To observe the natural evolution of tumors' dimensions in a group of patients, diagnosed with nonfunctional pituitary microadenomas based upon hormonal measurements and computed tomography scan.

METHOD

There is a retrospective observational study on 149 patients hospitalized in our Clinic between 1994 and 2006. Initially, all the pituitary hormones and the computed tomography were performed. Only nonfunctional microadenomas were included (the maximum diameter 11 mm). 69 patients were examined for a long period of time--29.75 +/- 24.79 months by CT scan and secretory profile, repeated at different periods of time.

RESULTS

At the end of 29.75 months, the aspect of microadenoma was still present, without any statistically significant changes of the diameter. One of the cases became macroadenoma and another proved to be a microprolactinoma. Only 5 cases of all 149 presented a double lesion. No case of pituitary apoplexy was registered. These observations lead to the conclusion that it is not necessary to repeat the computed tomography scan sooner than 2 years once the diagnosis ofincidentaloma was established.

Aryl hydrocarbon receptor-interacting protein and pituitary adenomas: a population-based study on subjects exposed to dioxin after the Seveso, Italy, accident

OBJECTIVE

The pathogenesis of sporadic pituitary tumors is unknown. Loss-of-function mutations of aryl hydrocarbon receptor-interacting protein (AIP) have been identified in patients with familial pituitary tumors. AIP is a chaperone protein with multifunction properties, including modulation of the transcriptional activity of the aryl hydrocarbon receptor, which mediates toxicological and carcinogenic dioxin effects.

DESIGN

We investigated the incidence of pituitary tumors in the Seveso population exposed to 2,3,7,8-tetrachlorodibenzo-para-dioxin following an industrial accident in 1976.

METHODS

Through the hospital discharge registration system of Lombardy Region, we identified incident cases of pituitary adenomas between 1976 and 1996 in the Seveso population, subdivided in zone A (n=804), B (n=5.941), and R (n=38.624) according to high, intermediate, and low exposure to dioxin respectively, and in the surrounding non-contaminated area, as reference (n=232 745).

RESULTS

We identified 42 pituitary adenomas in the reference area, 1 prolactinoma in zone A (rate ratio (RR) 6.2; 95% CI 0.9-45.5, P=0.07), 2 nonfuctioning pituitary tumors (NFPAs) in zone B (RR 1.9; 95% CI 0.5-7.7, P=0.39), and 3 prolactinomas and 2 NFPAs in zone R (RR 0.7; 95% CI 0.3-1.8, P=0.48).

CONCLUSIONS

The study is unique with regard to the availability of epidemiological and clinical data in an area of relatively pure dioxin exposure. The study indicates no statistically significant increase of incident pituitary tumors in this area, although the tendency toward a higher risk (three cases in zones A and B) of pituitary tumors in subjects exposed to high-intermediate dioxin concentrations in comparison with nonexposed population suggests the need for extended follow-up.

Patients cured from craniopharyngioma or nonfunctioning pituitary macroadenoma (NFMA) suffer similarly from increased daytime somnolence despite normal sleep patterns compared to healthy controls

OBJECTIVE

Adults patients previously treated for craniopharyngioma have increased general and physical fatigue compared to healthy controls. This could be related to disturbed sleep patterns. The aim of this study was to compare sleepiness and sleep patterns in those patients to healthy controls and to patients treated for nonfunctioning macroadenomas (NFMA) of the pituitary.

DESIGN

Case-control study.

PATIENTS AND METHODS

Sleepiness and sleep patterns were assessed in 27 adult patients [14 men, 8 patients diagnosed at childhood age, mean age of 53 years (range 27-80 year)] after long-term follow-up and compared to 50 healthy controls and 38 age-, gender- and BMI-matched patients with NFMA. We used two validated questionnaires for sleep parameters (Epworth sleepiness score and Münchener Chronotype Questionnaire).

RESULTS

Sleep patterns (onset, sleep timing, duration and rise time) were not statistically different between the three groups. However, daytime sleepiness scores were increased in patients treated for craniopharyngioma compared to healthy controls, but not different from patients with NFMA. Thirty-three percent of patients with craniopharyngiomas had ESS scores above 10 compared to 8% of healthy controls (P = 0.005), indicating severe daytime hypersomnolence. Neither type of surgery, previous radiotherapy, or age at diagnosis influenced the sleepiness scores in patients with craniopharyngioma.

CONCLUSION

Patients treated for craniopharyngioma or NFMA have increased daytime somnolence despite normal sleep patterns, compared to healthy subjects. The results indicate that increased daytime somnolence is a general consequence of large tumours, and/or their treatment, in the hypothalamic/pituitary region, rather than a specific feature of craniopharyngiomas per se.

Aryl hydrocarbon receptor interacting protein (AIP) gene mutation analysis in children and adolescents with sporadic pituitary adenomas

OBJECTIVE

Pituitary adenomas occur rarely in childhood and adolescence. Pituitary adenoma predisposition (PAP) has been recently associated with germline mutations in the aryl hydrocarbon receptor interacting protein (AIP) gene. The aim of the study was to examine the proportion of germline AIP mutations in apparently sporadic paediatric pituitary adenomas.

DESIGN

Genomic DNA was analysed for mutations in the AIP gene, by PCR amplification and direct sequencing.

PATIENTS

A population-based cohort consisting of 36 apparently sporadic paediatric pituitary adenoma patients, referred to two medical centres in Italy, was included in the study. Patients were either less than 18 years at diagnosis, or showed clinical evidence of adenoma development before the age of 18 years.

RESULTS

A heterozygous in-frame deletion Y248del (c.742_744delTAC) was identified in one GH-secreting adenoma patient. Loss of heterozygosity (LOH) analysis of tumour DNA revealed the loss of the wild-type allele. First degree relatives carrying the mutation were clinically unaffected.

CONCLUSIONS

While mutations were absent in non-GH-secreting adenoma patients, germline AIP mutations can be found in children and adolescents with GH-secreting tumours, even in the absence of family history. The present study reports the AIP mutation analysis results on patients of a single ethnic origin. Clearly, further studies are needed to improve our knowledge on the role of AIP in paediatric pituitary adenomas.

Replacement therapy with growth hormone and pituitary tumor recurrence: the relevance of the problem

Most cases of adult GH deficiency (AGHD) result from hypothalamic-pituitary tumors or their treatment. Some experimental and clinical observations suggest that GH may possess a mitogenic potential, thus raising the question of whether it is a safe treatment in patients with a previous pituitary tumor. Few study results have been reported on this topic. All of them have inevitable methodological flaws that limit their conclusions. However, all studies report that replacement therapy with GH does not seem to increase the risk of tumor progression or recurrence, when compared to historical or matched controls. Considering the slow-growing nature of most of these benign tumors and the absence of conclusive evidence from the available studies, a continuous imaging surveillance and longer follow-up periods are nevertheless mandatory for a definite statement on the safety of GH treatment in patients with previous pituitary tumors.

Patients with craniopharyngiomas: therapeutical difficulties with growth hormone

Craniopharyngioma (CP) is a rare and benign tumor of the pituitary region. It is the second cause of hypopituitarism in children and the third in adults. Multiple pituitary deficiencies or panhypopituitarism and diabetes insipidus are very frequent and their prevalence increases significantly after neurosurgery. In patients with GH deficiency (GHD), recombinant GH (rGH) replacement is recommended, after a near complete surgical excision of CP and exclusion of tumor progression. The risk of CP recurrence or progression due to rGH therapy is unproven. Treatment with rGH improves significantly the quality of life (QoL), although body composition and lipid abnormalities are not modified. At the data lock 2003, in the Hypopituitary Control and Complications Study (HypoCCS) Italian Database 90 patients with CP were included. Adulthood onset (AO) hypopituitarism had been diagnosed in two/thirds of them. They had worse QoL than their childhood onset (CO)-counterpart. During 3-yr rGH treatment mean body mass index, fat mass percentage, and both hip and waist circumferences decreased significantly only in CO patients. Accordingly, total cholesterol and triglycerides decreased, and HDL-cholesterol increased significantly in CO- but not in AO-patients. Analysis of dose titration showed that CO- were treated with higher rGH doses than AO-patients.

Prevalence of GH and other anterior pituitary hormone deficiencies in adults with nonsecreting pituitary microadenomas and normal serum IGF-1 levels

OBJECTIVE

GH is usually the first pituitary hormone to be affected following a pathological insult to the pituitary; however, data on the prevalence of GH deficiency in patients with nonsecreting pituitary microadenomas and normal serum IGF-1 levels are scarce. This study aims to evaluate the prevalence of GH and other anterior pituitary hormone deficiencies, and to determine whether microadenomas per se could be associated with reduced GH response rates to GHRH-arginine stimulation.

DESIGN

Analytical, retrospective, two-site case-control study.

PATIENTS AND METHODS

Thirty-eight patients with nonsecreting pituitary microadenomas (mean size 4.2 mm) and normal serum IGF-1 levels were studied. Anterior pituitary function testing, including the GHRH-arginine test to examine GH reserve, was performed in all patients. Serum IGF-1 levels and peak GH levels in the patients that passed the GHRH-arginine test were compared with 22 age- and BMI-matched healthy controls.

RESULTS

Nineteen patients (50%) failed the GHRH-arginine test and had higher body mass index (BMI) than those that passed the GHRH-arginine test and healthy controls. Peak GH levels in patients that passed the GHRH-arginine test were lower compared to healthy controls and 19 patients (50%) had at least one other pituitary hormone deficit. A negative correlation (r = -0.42, P < 0.01) between peak GH levels and BMI was identified, but no correlations were found between peak GH and serum IGF-1 levels.

CONCLUSIONS

Our data demonstrated that a substantial number of patients with nonsecreting pituitary microadenomas failed the GHRH-arginine test despite normal serum IGF-1 levels, and had at least one other pituitary hormone deficiency, suggesting that nonsecreting microadenomas may not be clinically harmless. We therefore recommend long-term follow-up with periodic basal pituitary function testing, and to consider dynamic pituitary testing should clinical symptoms arise in these patients.