Hypopituitarism in the elderly: a narrative review on clinical management of hypothalamic-pituitary-gonadal, hypothalamic-pituitary-thyroid and hypothalamic-pituitary-adrenal axes dysfunction

Hypopituitarism is an uncommon and under-investigated endocrine disorder in old age since signs and symptoms are unspecific and, at least in part, can be attributed to the physiological effects of aging and related co-morbidities. Clinical presentation is often insidious being characterized by non-specific manifestations, such as weight gain, fatigue, low muscle strength, bradipsychism, hypotension or intolerance to cold. In these circumstances, hypopituitarism is a rarely life-threatening condition, but evolution may be more dramatic as a result of pituitary apoplexy, or when a serious condition of adrenal insufficiency suddenly occurs. Clinical presentation depends on the effects that each pituitary deficit can cause, and on their mutual relationship, but also, inevitably, it depends on the severity and duration of the deficit itself, as well as on the general condition of the patient. Indeed, indications and methods of hormone replacement therapy must include the need to normalize the endocrine profile without contributing to the worsening of intercurrent diseases, such as those of glucose and bone metabolism, and the cardiovascular system, or to the increasing cancer risk. Hormonal requirements of elderly patients are reduced compared to young adults, but a prompt diagnosis and appropriate treatment of pituitary deficiencies are strongly recommended, also in this age range.

Systemic hypertension counteracts potential benefits of growth hormone replacement therapy on left ventricular remodeling in adults with growth hormone deficiency

BACKGROUND

Systemic Hypertension (SH) is the main cause of left ventricular (LV) hypertrophy in the general population, but only scanty data are available on LV geometric remodeling (LVGR) in hypertensive patients with GH deficiency (GHD).

AIM

We investigated hypertensive LVGR in adult-onset GHD patients, before (T0) and after 55±16 months (T1) of individualized GH replacement therapy (GHRT).

SUBJECTS

Fifty-one patients, aged 45±15 yr, 29 women, were enrolled. Fifteen patients met criteria for SH (group A) whereas 36 were normotensive (group B).

METHODS

An echocardiogram was performed on all patients, at least twice (at T0 and T1). LV geometric remodeling as a relationship between LV mass (LVM) index and relative wall thickness (RWT), LV volumes, and ejection fraction were measured.

RESULTS

At T0, group A showed higher LV mass and LVM index values than group B; LV hypertrophy was found in 40% and 22% of patients, respectively (p=0.06). At T1, IGF-I levels had increased significantly in both groups. LV hypertrophy rate consistently increased in group A (from 40 to 60%, p<0.05), whereas slightly decreased in group B (from 22 to 19%, ns). Body surface area (p<0.001), age (p<0.05), and systolic blood pressure (p<0.05) were main determinants of LVM at multivariate analysis.

CONCLUSIONS

Along with body surface area and age, SH was significantly related to abnormal LVGR (LV hypertrophy) in GHD patients. As a result, blood pressure management and caloric intake restrictions are deemed necessary for this subset of patients.

Cell proliferation parameters and apoptosis indices in pituitary macroadenomas

BACKGROUND

Pituitary adenomas are usually well-differentiated tumors but may show locally aggressive behavior.

AIM

To investigate the relationship between proliferation and apoptosis parameters and tumor recurrence in a series of 20 radically resected pituitary macroadenomas (11 functioning, 9 non-functioning).

MATERIALS AND METHODS

Proliferative activity and DNA ploidy were analyzed by flow cytometry (FCM) on fresh surgical specimens. Immunohistochemistry for Ki-67/MIB-1 and for the anti-apoptotic protein Bcl-2 was performed on paraffin-embedded specimens from the same tumors. Tumor regrowth was evaluated by magnetic resonance imaging (MRI).

RESULTS

Six adenomas recurred after surgery, regardless of hormonal hypersecretion. Pre-surgical tumor size was significantly higher in recurrent than in non-recurrent adenomas (p=0.003). Pre-surgical MRI demonstrated cavernous sinus (CS) invasiveness in all recurrent tumors, while none of the non-invasive adenomas recurred (p=0.042, by Fisher's exact test). The DNA content was aneuploid in 5/20 adenomas, one of which recurred. Cell percentages in the S (%SPF) and G2+M (%G2-M) phases and proliferative index (PI) (PI=%SPF+%G2-M) were significantly higher in aneuploid than in diploid adenomas (p<0.05), but no significant differences concerning all FCM parameters were observed between recurrent and non-recurrent adenomas. Similarly, MIB-1 did not show a significant difference of expression between recurrent and non-recurrent adenomas (p=0.33). Bcl-2 immunoreactivity was detected in 12/15 pituitary adenomas, involving 63±35% of tumor cells, regardless of tumor recurrence.

CONCLUSIONS

In this group of radically resected pituitary macroadenomas, neuroradiological finding of CS invasiveness--but not FCM parameters nor MIB-1 and Bcl-2 expression--is useful for predicting tumor recurrence.

High prevalence of coronary calcifications and increased risk for coronary heart disease in adults with growth hormone deficiency

Assessment of coronary calcium deposits (CCD) by coronary computed tomography (CT) was recently introduced for evaluation of risk to develop events related to coronary heart disease (CHD). We investigated occurrence of CCD in 19 hypopituitary patients (patients), 34 healthy (H) subjects (H controls) and 36 patients with a similar rate of diabetes mellitus and hypertension (morbid, M), but without pituitary diseases (M controls). Patients were replaced with L-thyroxine, cortone acetate, sex hormones and/or desmopressin, but never with GH. Unenhanced coronary CT was performed by 16-row multislice scanner. Framingham score (FS) was calculated and CCD were measured by Agatston score (AS) in all subjects. AS>10 indicates increased CHD risk. CCD and AS >10 were detected in 50% and 33% of patients, respectively. Prevalence of CCD and mean AS were higher in patients than in H and M controls. In patients, AS was negatively dependent on IGF-I levels (p<0.01) and IGF-I SD (p<0.05), and AS >10 was associated with occurrence of hypertension (p<0.02) and hyperinsulinism (p<0.05). Men and women showed the same prevalence of AS >10 (25 vs 31%). FS and AS correlated significantly (rs=0.33, p<0.001), but CCD were detected also in 3/11 patients with low FS. In conclusion, 58% of patients were at CHD risk on the basis of increased FS and/or AS, above all if they were hypertensive and/or showed hyperinsulinism. CCD were detected also in patients with low FS. CHD risk is higher in women. Risk of CCD is increased in patients with low IGF-I levels.

Increased prevalence of acromegaly in a highly polluted area

OBJECTIVE

Despite the contribution of national registries and population-based reports, data concerning the epidemiology of acromegaly is scanty. In addition, the role of the environmental context has not been investigated.

DESIGN

Epidemiology of acromegaly was studied in the province of Messina (Sicily, Italy), focusing on the influence of environmental factors.

METHODS

Four zones, characterized by different degrees of exposition to environmental toxins due to industrial pollution, were identified in the province: area A (76,338 inhabitants), area B (287,328 inhabitants), area C (243,381 inhabitants), and area D (47,554 inhabitants) at low, middle-low, middle, and high industrial density respectively. We identified all acromegalics who were born and resided in the province of Messina, among patients either referred to our endocrine unit or referred elsewhere but recorded in the archives of the provincial healthcare agency.

RESULTS

In the province of Messina, we found 64 patients (2 in area A, 24 in area B, 28 in area C, and 10 in area D). Macroadenomas were 60%, the male/female ratio was 1, and mean age at diagnosis (±s.e.m.) was 45.4±1.6 years. Overall, prevalence was 97 c.p.m. in the province (26 c.p.m. in area A, 84 c.p.m. in area B, 115 c.p.m. in area C, and 210 c.p.m. in area D). Risk ratio (RR), calculated in every area assuming area A as a reference, showed an increased risk of developing acromegaly in people residing in area D (RR=8.03; P<0.0014).

CONCLUSION

This study confirms the prevalence of acromegaly reported recently. The increased risk of developing this disease in area D suggests that the pathogenetic role of environmental context needs to be better evaluated.

Non-functioning pituitary adenomas infrequently harbor G-protein gene mutations

BACKGROUND

Mutations of the genes encoding the alpha subunit of the stimulatory G protein (Gs) and of the inhibiting Gi2 protein (GNAS1 and GNAI2 genes, respectively) have been described in various endocrine neoplasias, including pituitary tumors.

AIM

To search for mutations of GNAS1 and GNAI2 in a continuous series of non-functioning pituitary adenoma (NFPA) patients neurosurgically treated.

SUBJECTS AND METHODS

The surgical samples of 22 patients who have been defined and characterized on a clinical, biochemical, histological, and immunohistochemical point of view have been processed for investigating the presence of the above mutations by PCR amplification of the hot spots exons 8 and 9 of GNAS1, and exons 5 and 6 of GNAI2, followed by direct sequencing. Moreover, the promoter region of GNAI2, in order to assess the prevalence of single nucleotide polymorphisms (SNP), was investigated in the same series.

RESULTS

A CGT>TGT mutation at codon 201 of GNAS1 gene in a single case of NFPA was found, but no mutation of GNAI2A was demonstrated.

CONCLUSIONS

This finding suggests and confirms that G-protein mutations are rare and not crucial in NFPA development. Additionally, we found a silent SNP at codon 318 in the promoter of the Gi2alpha gene in one out of the 22 NFPA.

Clinical presentation and outcome of pituitary adenomas in teenagers

OBJECTIVE

Pituitary adenomas rarely occur in childhood and adolescence, but their mass effect and endocrine abnormalities can compromise both quality and length of life. In this study we evaluated the symptoms at onset and the long-term consequences induced in teenagers by functioning or nonfunctioning pituitary adenomas.

DESIGN AND PATIENTS

Clinical, biochemical and neuroradiological data of 44 young patients (12 males and 32 females, aged 16.3 +/- 1.9 years at diagnosis) with pituitary adenomas were evaluated retrospectively at baseline and after therapy. Patients underwent surgery, radiotherapy and/or medical treatment depending on clinical history and endocrine secretion of the tumour. Follow-up ranged from 8 to 252 months (median 55 months).

MEASUREMENTS

Baseline and dynamic pituitary function were evaluated in all cases at diagnosis and after treatments. Magnetic resonance imaging (MRI) or computed tomography (CT) scan were performed before therapy and during follow-up. Hormone levels were measured using commercial radioimmunologic or immunoradiometric methods.

RESULTS

Pituitary macroadenomas (group 1) or microadenomas (group 2) were found in 61% and 39% of cases, respectively. Overall, 68% were PRL-secreting, 7% GH-secreting, 5% ACTH-secreting and 20% nonfunctioning. The most frequent symptoms at onset were oligoamenorrhoea (62%) and galactorrhoea (59%) in the girls, and headache (58%) in the boys. Pubertal development was delayed in 12/27 (44%) cases with macroadenoma. Growth failure was observed in 4/44 (9%) patients (3 in group 1 and 1 in group 2). At diagnosis, hypopituitarism was detected in 10/27 (37%) patients with macroadenoma. Surgery alone cured 4/18 (22%) and 4/9 (44%) patients in group 1 and group 2, respectively. Adjuvant therapies (second surgery and/or radiotherapy and/or medical treatment) cured the disease in 2/13 (15%) patients with macroadenoma and allowed a persistent normalization in other 4/13 (31%) and 2/4 (50%) cases in group 1 and group 2, respectively. Medical treatment alone cured 2/9 (22%) patients with PRL-secreting macroadenoma and normalized PRL levels in another six (66%) with macroprolactinoma and in 2/7 (28%) patients with microprolactinoma.

CONCLUSION

Delay of growth was rarely observed in teenagers with pituitary adenomas. At the onset of the disease, many girls complained of oligoamenorrhoea and galactorrhoea, while headache and delay of pubertal development were the symptoms more frequently referred by boys. Surgery alone was effective in a minority of patients and adjuvant therapies were helpful to obtain the remission of the disease in many cases. In patients with PRL-secreting pituitary adenoma, medical treatment, both as first choice or as adjuvant therapy, normalizes serum PRL levels in 14/27 (52%) cases.

Impairment of GH secretion in adults with primary empty sella

Primary empty sella (PES) is generally not associated with overt endocrine abnormalities, although mild hyperprolactinemia and, in children, deficient GH secretion have been reported. The aim of this multi-center collaborative study was to evaluate basal and stimulated GH secretion in a large series of adult PES patients. The study group consisted of 51 patients [41 women and 10 men, age range: 20-78 yr; (mean+/-SD) 47+/-11 yr]; results were compared with those in normal subjects (Ns) (Ns: no.=110, 55 women, age: 20-50 yr, 37+/-14 yr), and in hypopituitaric patients (HYP) with GH deficiency (HYP: no.=44,17 women, age: 20-72, 49+/-16 yr). Baseline IGF-I levels and GH responses to insulin-induced hypoglycemia (insulin tolerance test, ITT) and/or GHRH+arginine (ARG) stimulation tests were evaluated. PES patients were also subdivided according to BMI in lean (BMI <28 kg/M2 no.=22) or obese (BMI >28 kg/m2 no.=29). PES patients had serum total IGF-I concentrations (mean+/-SE: 142.2+/-9.6 ng/ml) higher than HYP patients (77.4+/-6.4 ng/ml, p<0.001), but lower than Ns (213.3+/-17.2 ng/ml, p<0.005), with no differences between lean and obese PES subjects. The increase in serum GH concentrations following ITT and/or GHRH+ARG stimulation tests, although higher than that observed in HYP patients, was markedly reduced with respect to Ns. No difference was observed in the GH response to provocative tests between lean and obese PES patients. When individual GH responses to ITT or GHRH+ARG were taken into account, a large proportion of PES patients (52% after ITT, 61% after GHRH+ARG) showed a GH peak increase below the 1st centile of normal limits. Serum IGF-I levels in PES patients with blunted GH responses to provocative tests were significantly (p<0.001) lower in PES patients with normal GH responses, and a positive correlation was observed between IGF-I levels and serum GH peak concentrations after GHRH+ARG. In conclusion, the results of the present study provide evidence that adult PES patients often have an impairment of GH secretion, as indicated by the blunted GH response to ITT and GHRH+ARG provocative tests, and by the reduction in serum IGF-I levels. These changes are independent of body mass.

Abnormalities of hypothalamic-pituitary-thyroid axis in patients with primary empty sella

Primary empty sella (PES) is a very frequent neuroradiological finding in the general population, that can induce hypopituitarism. Some studies focused on the association of PES with GH deficiency (GHD) or hypogonadotropic hypogonadism (HH), while data regarding the involvement of hypothalamic-pituitary-thyroid (HPT) axis, despite sporadic reports of central hypothyroidism, or the occurrence of hypoadrenalism (HA) are scanty. In this study, thyroid function and TSH response to exogenous TRH injection (TRH/TSH) were investigated in 43 patients [10 men and 33 women; aged (mean +/- SD), 48+/-12 yr] with PES: 22 patients had total and 21 partial PES. Forty healthy subjects (9 men and 31 women; aged 46+/-12 yr) were enrolled as a control group. Central hypothyroidism was found only in 2/43 cases, whereas one patient showed primary hypothyroidism. In euthyroid patients, mean serum TSH levels were significantly lower than controls (TSH: 1.0+/-0.7 vs 1.4+/-0.6 mU/l, p<0.01) and 79% of them showed abnormal TRH/TSH responses (TRH test was performed in 34 euthyroid patients: 17 cases with total and 17 cases with partial PES), but mean serum free T4 (FT4) and free T3 (FT3) values were not significantly lower than controls (FT4: 15.9+/-0.4 vs 15.0+/-2.1 pmol/l, p=NS; FT3: 5.3+/-1.2 vs 5.8+/-1.5 pmol/l, p=NS). Moreover, no significant differences were evident in mean serum TSH, FT4 and FT3 between patients with total and partial PES (TSH: 1.1+/-0.7 vs 0.9+/-0.8 mU/l, p=NS; FT4: 16.3+/-2.6 vs 15.7+/-2.2 pmol/l, p=NS; FT3: 5.4+/-1.3 vs 5.2+/-0.8 pmol/l, p=NS) and the TRH/TSH peak was impaired or exaggerated/delayed in 9 and 3 patients with total and in 12 and 3 cases with partial PES. No significant differences in the prevalence of abnormal TRH/TSH responsiveness were found between patients with partial or total PES (chi2=1.6, p=NS). Other impairment of pituitary function was detected in 23/43 patients: GHD was present in 15 cases, HH in 11 and central HA in 5 patients. Isolated or combined hypopituitarism was present in 17 and in 6 patients, respectively. In conclusion, pituitary dysfunction is very frequent in patients with PES, but central hypothyroidism occurs rarely. The entity of arachnoid herniation into the sellar fossa does not play a significant role on the degree of HPT axis dysfunction.

Exercise-related female reproductive dysfunction

Clinical or biochemical abnormalities of gonadal function, consisting of delayed puberty, luteal phase deficiency, oligo-amenorrhea or anovulation, occur in girls and women participating in strenuous sports. The evidence of a causal relationship between athletic activity and menstrual dysfunction has led to increased interest, also because the number of women who practice sports has increased rapidly. The pathogenesis of exercise-related female reproductive dysfunction (ERFRD) is not completely clarified. The heterogeneity of sports practice, the role of overtraining and other factors, as adequate calorie balance or the assumption of exogenous steroids, could play a primary role in the comprehension of the pathogenic mechanisms of reproductive dysfunction. The interest of physicians about ERFRD is also due to the consequences of reduced gonadal function on women's health. Apart from some short-term transient effects (i.e. on muscle, genito-urinary tract or behavior), hypoestrogenemia can induce long-term deleterious effects, as premature osteoporosis and lifelong impairment of skeletal structure. In view of the possible short-term (infertility) and long-term (osteoporosis) consequences of ERFRD, correct physical training and adequate diet approach are mandatory to prevent or to revert neuroendocrine abnormalities so frequently reported in girls and women participating in recreational or competitive athletic activities.

Effectiveness of slow-release lanreotide in previously operated and untreated patients with GH-secreting pituitary macroadenoma

The aim of this study was to verify whether treatment with slow-release lanreotide (SRL) before surgery is useful in the management of patients with GH-secreting pituitary macroadenoma. Twenty untreated acromegalics were enrolled randomly in two groups. Ten patients (group 1: 2 males and 8 females aged 44.5 +/- 4.3 years) underwent surgery via transsphenoidal access. Only one of them was cured by surgery, whereas the other nine were treated with SRL. In the other ten patients (group 2: 3 males and 7 females aged 43.2 +/- 12.3 years), transsphenoidal surgery followed SRL treatment. Surgery induced the normalization of GH and IGF-1 levels in four group 2 patients - three of them had shown an evident shrinkage of the tumor after SRL treatment. After surgery, group 1 showed a significant decrease of mean IGF-1 (580 +/- 63 vs. 789 +/- 64 ng/ml, p < 0.02), but not of GH values (26.1 +/- 9.8 vs. 44.8 +/- 19.3 ng/ml, NS); the cured patient was excluded from the following evaluations. Group 2 showed an evident, but not significant, decrease of both GH and IGF-1 values compared to values measured at the end of medical treatment (GH: 22.4 +/- 9.7 vs. 7.7 +/- 4.7 ng/ml, NS. IGF-1: 570 +/- 69 vs. 402 +/- 58 ng/ml, NS). Gonadal, thyroid and adrenal impairment was evident in six, four and no patients in group 1 and in three, two and one patients in group 2, respectively. SRL 30 mg was administered every 14 days for three months and then every 10 days until the 6th month. Before SRL treatment, mean GH and IGF-1 levels did not differ significantly in group 1 vs. group 2 (GH: 29.3 +/- 10.5 vs. 43.4 +/- 22.0 ng/ml; IGF-1: 633 +/- 38 vs. 778 +/- 83 ng/ml). In group 1, a significant decrease of serum GH, but not of IGF-1 levels, was achieved at the end of 1st trimester of SRL (GH: 17.6 +/- 5.4 ng/ml, p < 0.05. IGF-1: 540 +/- 48 ng/ml, NS), whereas a significant decrease in both GH and IGF-1 values was evident during the 2nd trimester (GH: 6.1 +/- 3.0 ng/ml, p < 0.05. IGF-1: 433 +/- 74 ng/ml, p < 0.02). Serum GH levels, measured during the 2nd trimester of SRL therapy, were also significantly lower than levels measured at the end of the 1st trimester (p < 0.05). Group 2 serum GH and IGF-1 levels were not significantly decreased at the end of the 1st trimester (GH: 27.2 +/- 12.1 ng/ml, NS. IGF-1: 698 +/- 74 ng/ml, NS), whereas only serum IGF-1 (570 +/- 69 ng/ml, p < 0.05) was significantly reduced during the 2nd trimester of SRL (GH: 22.4 +/- 9.7 ng/ml, NS). Serum GH and IGF-I fell in the normal range in 4 patients in group 1 and one in group 2 at the end of the second trimester of SRL therapy. Independently of the trial applied, the mean clinical score level ameliorated significantly in both groups (group 1: p < 0.0005; group 2: p < 0.0001). In both groups, the proportion of patients complaining of headache and tissue swelling and the score level of headache, tissue swelling and excessive sweating decreased significantly. In group 1 the score level of fatigue and arthralgia also decreased significantly. In conclusion, this study proves that in patients with GH-secreting pituitary macroadenoma: (i) surgery followed by SRL induces a better clinical and biochemical status than SRL alone; (ii) SRL treatment before surgery ameliorates the clinical and biochemical outcome and reduces the prevalence of hypopituitarism due to surgery.

Results of a two-year treatment with slow release lanreotide in acromegaly

In this open sequential study we evaluated the long-term effectiveness and tolerability of the i.m. administration of slow release lanreotide 30 mg (SRL) in 18 acromegalics (7 M/11 F, age 50.9+/-12.7 yr). Baseline mean GH and IGF-1 levels were 15.8+/-6.6 ng/ml and 702+/-74 ng/ml, respectively. Four hours, 1, 7, and 14 days after SRL, mean GH levels were 8.9+/-5.9 (p < 0.005), 11.4+/-6.9 (p < 0.05), 9.1+/-4.5 (p < 0.05), and 9.1+/-4.1 ng/ml (p < 0.05), respectively; and the IGF-1 values at 1, 7, and 14 days were 624+/-77 (p < 0.05), 555+/-83 (p < 0.001), and 467+/-58 ng/ml (p < 0.0001), respectively. Four hours after SRL administration GH was < 2.5 ng/ml in 11 patients and decreased 85% of the basal value, without normalizing, in another case. In the following 2 weeks, 7 and 2 patients maintained GH < 2.5 ng/ ml or < 50% of baseline; 3 and 2 of them attained IGF-1 values in the normal range or < 50% of basal levels. A patient developed acute pancreatitis after the injection of the drug and therefore stopped the treatment. Another patient did not continue SRL, and she was turned on octreotide, s.c. administered (OCT), because only the latter treatment ameliorated significantly the headache. In 16/18 patients the treatment was continued until the 24th month. SRL was administered every 14 days until the 24th month in 3 cases, whereas in 13 patients the dose schedule was increased every 10 days since the 7th month because they did not normalize serum GH and IGF-1 levels. In these 16 patients baseline GH and IGF-1 levels were 10.0+/-2.5 ng/ml and 671+/-75 ng/ml, respectively. At the 1st, 3rd, and 6th month of treatment mean GH levels fell to 5.4+/-1.4 (p < 0.05), 5.3+/-1.8 (p < 0.05), and 5.0+/-1.6 (p < 0.05) ng/ml, respectively; and IGF-1 declined to 511+/-87 (p < 0.005), 565+/-85 (p < 0.05), and 525+/-94 (p < 0.01) ng/ml, respectively. Throughout the first semester GH was < 2.5 ng/ml in 5 patients and decreased > 50% in another three. IGF-1 levels normalized in 3/5. Throughout the following 18 months of treatment, mean GH (3.4+/-1.0 ng/ml) and IGF-1 (413+/-75 ng/ml) values decreased significantly in comparison with both the baseline concentrations (GH p < 0.01, IGF-1 p < 0.001) and the levels measured during the 1st semester of treatment (GH p < 0.05, IGF-1 p < 0.001). GH remained < 2.5 ng/ml in 11 patients, and in 8/11 cases IGF-1 fell in the normal range. Serum GH and IGF-1 levels decreased by more than 50% of baseline levels in 2 other cases. At MRI, pituitary adenoma was no longer evident in one patient previously treated with OCT and significantly decreased in another patient previously treated with surgery plus radiotherapy, as well as in a patient previously untreated. During treatment the percentage of patients complaining of headache and fatigue decreased significantly (chi2, p < 0.05 and p < 0.0005, respectively). Overall, the headache (p < 0.005), arthralgia (p < 0.05), and paresthesia (p < 0.01) ameliorated significantly. Ultrasound scan showed gallbladder sludge or sand-like stones in 5/11 patients. This study, which is one of the longest surveys on a relatively large series of acromegalics treated with SRL, confirms the long-term effectiveness of this drug for the treatment of patients with active acromegaly. SRL decreases significantly GH and IGF-1 in most cases and induces the shrinkage of the pituitary tumor in some patients previously either untreated or both treated for acromegaly. SRL improves significantly clinical symptoms and it is well tolerated.

Goiter and impairment of thyroid function in acromegalic patients: basal evaluation and follow-up

AIMS

We evaluated morphological, biochemical and cytological thyroid parameters in acromegalic patients, investigated before and after treatment for acromegaly.

PATIENTS

28 acromegalics were investigated before and, in 18 cases, after 2-7 years of therapy. Fourteen patients were from areas of moderate iodine deficiency in Southern Italy. One patient underwent thyroidectomy before entering this study.

RESULTS

19 patients were euthyroid (FT4: 17.7 +/- 0.8 pmol/l and FT3 4.6 +/- 0.2 pmol/l), but TSH was undetectable in 5/19. Among them, TRH-stimulated TSH increase was absent/impaired or exaggerated/delayed in 9 and one cases, respectively. Decreased FT3 and/or FT4 values with low/normal TSH values were detected in 7 cases; TRH-stimulated TSH response was absent/impaired in 2 patients and exaggerated/delayed in another two. Increased free T4 and free T3 concentrations with undetectable TSH levels were found in one. Two euthyroid patients had high TPOAb levels. Goiter was diagnosed in 21 cases and nodules were found in 14/21. 99Tc scintiscan showed "cold" areas in 13/14 cases and a "hot" nodule in the hyperthyroid patient. Acromegalics from iodine deficient areas showed a not significant increase of prevalence of goiter (86 vs. 71 %) and of mean thyroid volume (35 +/- 7 vs. 28 +/- 4 ml, NS), compared to others. Thyroid volume (TV) did not correlate with GH, IGF-1 and TSH levels, the area under the curve of insulin-increase during OGTT, the age of patients or the duration of acromegaly. Fine needle aspiration biopsy (FNAB), performed in 11/14 patients with nodular goiter, showed colloid nodules in 8 cases, hyperplastic nodules in 2 and an adenomatous nodule in one. Neurosurgery, radiotherapy or medical treatment for acromegaly induced a significant decrease of mean GH and IGF-1 levels (21.5 +/- 8.5 vs. 12.9 +/- 9.6 ng/ml, p< 0.005 and 747 +/- 94 vs. 503 +/- 88 ng/ml, p < 0.02, respectively), but both GH and IGF-1 values normalized only in 3 cases. No significant variation of mean TSH levels was found. Although TV normalized in 3 patients, ultrasound evaluation showed a not significant decrease of mean TV and no changes in the diameter and number of nodules. FNAB was unchanged.

CONCLUSIONS

Our results suggest that, despite no correlation between serum GH and IGF-1 levels and thyroid volume being found, a decrease in serum GH and IGF-1 levels has favourable effects on thyroid status.

Unusual MRI finding of multiple adenomas in the pituitary gland: a case report and review of the literature

The simultaneous occurrence of multiple adenomas in the pituitary gland is a rare event. We report the coexistence of three non functioning pituitary microadenomas in a 37-year-old woman, referred to us for oligomenorrhea and headache. Biochemical evaluation revealed prolactin (131 U/liters), follicle-stimulating hormone (4.1 U/liters), luteinizing hormone (3.9 U/liters), 17beta-estradiol (74 pg/mL), free (2.0 pg/mL) and total testosterone (0.5 ng/mL), dehydroepiandrosterone-sulfate (3.5 microg/mL), 17OH-progesterone (0.8 ng/mL), cortisol (13.1 microg/dL), free triiodothyronine (4.8 pmol/L), free thyroxine (18.5 pmol/liters), thyrotropin (1.6 mU/L), and growth hormone (0.2 ng/mL) levels in the normal range, as for as the response to dynamic endocrine tests. MRI showed an enlarged sella turcica, occupied by three distinct hypointense areas that measured less than 5 mm in diameter in the left, medium and right side of the pituitary, respectively. This finding was confirmed 6 months later by a second MRI that revealed also a light increase in microadenomas dimensions. The patient, therefore, underwent neurosurgery by transfenoidal approach. Histologic examination showed no morphologic differences between the specimens obtained from the different microadenomas. Immunohistochemistry evaluation revealed a positive staining for the common alpha-subunit of glycoproteic hormones and negative for the other pituitary hormones tested, while electron microscopy showed cells with a poor secretory apparatus and a variable grade of cell differentiation. In conclusion, we report the fifth case described with multiple pituitary adenomas diagnosed in vivo and the first with three coexisting tumors revealed by MRI before neurosurgery. The occurrence of multiple pituitary tumors emphasizes the role of pituitary and extrahypophiseal factors in the clonal expansion of genetically altered cells.

Cabergoline: a first-choice treatment in patients with previously untreated prolactin-secreting pituitary adenoma

Cabergoline (CAB) treatment is an effective, safe and well tolerated approach for hyperprolactinemia. We investigated the efficacy of 24-month treatment with CAB in 37 patients with previously untreated PRL-secreting pituitary adenoma and evaluated the hormonal and neuroradiological changes after the discontinuation of long-term therapy. Eleven patients with macroprolactinoma (1M/10F) and 26 with microprolactinoma (4M/22F) started treatment taking 0.25 mg CAB twice a week for 4 weeks. The dose was increased stepwise in 0.5 mg increments until reaching lowest maximally effective and tolerated dose. CAB was withdrawn before the end of the study in 6 women who became pregnant and in one patient who showed a slight increase of the macroadenoma at MRI. During treatment, PRL levels decreased significantly in macro (11.1+/-1.1 vs 407.8+/-98.3 microg/l, p<0.001) and microprolactinomas (11.1+/-1.6 vs 193.8+/-23.4 microg/l, p<0.05) and normalized in all macro and in 23/26 microprolactinomas. In 3 cases PRL levels decreased but did not normalize because the appearance of side effects, such as nausea or hypotension, prevented the increase of the dose of CAB. The effective dose of drug correlated significantly with basal serum PRL levels (p<0.05) and with the pituitary tumor size (p<0.05). A significant decrease of the mean adenoma size was evident for macro (6.9+/-1.8 vs 16.0+/-1.8 mm, p<0.001) and microprolactinomas (3.0+/-0.5 vs 6.5+/-0.4 mm, p<0.001) at MRI. The tumor disappeared in 4 macroadenomas and in 11 microadenomas after 12 months of treatment. CAB withdrawal was followed by serum PRL increase in 13 cases after 3 months, in 6 after 6 months, in 2 after 9 months, and in one patient at the 12th month. Five patients showed normoprolactinemia with negative MRI after one year. Regular menses were restored in 7/10 macroprolactinomas and in all oligo-amenorrhoic patients with microadenoma; serum testosterone levels normalized in 2/3 hypogonadic men. Five out of 6 women become pregnant and had uneventful pregnancies which resulted in deliveries of normal babies. In conclusion, this study confirms the effectiveness and safety of CAB for patients with PRL-secreting pituitary adenoma and suggests that it can be considered a first choice treatment.

Coexistence of growth hormone-secreting pituitary adenoma and intracranial meningioma: a case report and review of the literature

The simultaneous occurrence of a pituitary adenoma and an intracranial meningioma is a rare event. We report the coexistence of an eosinophilic pituitary adenoma and a endotheliomatous meningioma, in the sellar region, and evaluate their endocrine, neuro-radiological and immunohistochemical pattern. A 47-year-old woman affected by acromegaly was referred to us. Serum GH level was 82 ng/ml and remained unresponsive to both OGTT (75 g per os) and iv. GHRH 1-29 (100 micrograms); IGF-1 was 807 ng/ml. Eight hours after acute sc administration of octreotide (100 micrograms) GH returned to normal levels (2.3 ng/ml). CT scan showed a large intra- and suprasellar mass involving the right cavernous sinus, with a retrosellar extension along the tentorium. A slight and inhomogeneous enhancement, with a periferal rim of bright signal was apparent at MRI. Conversely, the retrosellar component showed a bright homogeneous enhancement. The patient, therefore, underwent neurosurgery. Histological examination revealed the coexistence of 2 types of tissue: areas of endotheliomatous meningioma were interspersed among sheets of acidophilic adenoma tissue. Immunohistochemical analysis was performed in order to determine the relationship between the two masses: a positive staining for GH was shown in the areas of adenoma, as against for GHRH, neither in the adenomatous tissue nor in the slices of meningioma. Although MRI showed a latero-sellar post-surgical residual of meningioma, serum GH value was < 1 ng/ml. In conclusion, the relationship between the GH-secreting adenoma and the meningioma is unclear; however the GH-hypersecretion is not induced by a hypothetic GHRH-activity from the meningioma.