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Pituitary apoplexy during therapy with cabergoline in an adolescent male with prolactin-secreting macroadenoma.

Pituitary adenomas are rare in young patients. Prolactinomas are the most common type of pituitary adenomas in children older than 12 years, occurring more often in girls, at a 4.5:1 female-to-male ratio. The clinical presentation may vary according to the age and sex of the patient. Pituitary apoplexy is a rare life-threatening condition caused by a sudden infarction or hemorrhagic necrosis of the pituitary containing an adenoma. A wide variety of conditions can trigger apoplexy such as pituitary irradiation, general anesthesia, traumatic head injury, pituitary stimulatory tests and a wide variety of medications including bromocriptine. We report a case of a 16-year-old male patient with puberty arrest harboring a macroprolactinoma, who developed a sudden clinical picture of pituitary apoplexy during the 12th month of treatment with cabergoline.

Adenoma↗

Treatment of Cushing's disease with adrenal blocking drugs and megavoltage therapy to the pituitary.

Eighteen patients with Cushing's disease were seen over a 40-month period and considered for treatment by pituitary irradiation and adrenal blocking drugs. Fourteen patients entered the study and each received megavoltage therapy to give a mean dose of 4600 rad to the pituitary over 31 days. Each patient was treated for one (two patients) or two (12 patients) years with one or both of the adrenocortical enzyme inhibitors, metyrapone or aminoglutethmide to suppress cortisol secretion. Doses were adjusted to maintain urinary free cortisol secretion below 300 nmol/24 h. One patient failed to complete the trial. Normal urinary free cortisol excretion and plasma cortisol concentration were maintained after treatment in eight of the remaining 13 patients after therapy. Only one patient required cortisol replacement and normal menstrual function was restored in five of the six women. The remaining five patients relapsed and four were subsequently treated by total adrenalectomy. It was noted that the patients who responded to treatment were substantially younger than the therapeutic failures. It is suggested that this treatment is most useful in the management of younger patients.

Adrenocorticotropic Hormone↗

Responsiveness of irradiated rat anterior pituitary cells to hypothalamic releasing hormones is restored by treatment with growth hormone.

Hypopituitarism is a common sequela of irradiation in cancer patients. Here we report that recombinant human growth hormone (r-hGH) prevents cell death and restores secretory capacity of irradiated rat pituitary cells in vitro. Dispersed rat pituitary cells from male Sprague-Dawley rats, irradiated with a 9-Gy sublethal dose, were incubated with r-hGH before, after, or before and after irradiation. Treatment with GH resulted in increased cell survival, which reached its maximum at the concentration of 5 nM, with an EC(50) of 3.5 nM. Protective effects of GH on pituitary cells were more pronounced in cultures treated before and after irradiation. Similarly, beneficial effects of GH were observed on the secretory capacity of surviving cells. In fact, irradiated pituitary cells treated with GH secreted substantial amounts of GH, luteinizing hormone, follicle-stimulating hormone, prolactin, thyroid-stimulating hormone and adrenocorticotropic hormone in response to specific releasing hormones. Such effects of GH were prevented in the presence of the specific GH receptor antagonists B2036 and G120K. Our results show that r-hGH exerts a specific protective effect on irradiated rat pituitary cells and suggest possible use of GH as an adjuvant agent for prevention of postirradiation hypopituitarism.

Adrenocorticotropic Hormone↗

Plasma growth hormone profiles and sleep: a study of 13 treated acromegalics.

The plasma growth hormone profiles and sleep patterns of 13 treated male acromegalic patients, aged 29-67 years, were studied. All patients had undergone selective pituitary transsphenoidal surgery 4-9 years previously; five patients had also undergone supplemental pituitary irradiation. Blood samples were taken at 20-min intervals; the sleep patterns were obtained by EEG. GH reserve was assessed after insulin-induced hypoglycaemia and GHRH (1-44) with and without pyridostigmine. The profiles were analysed with the aid of the Pulsar program. Seven out of eight non-irradiated patients had 1-3 nocturnal GH peaks; in the irradiated group only one patient had a normal profile. The GH reserve after insulin-induced hypoglycaemia was normal in seven out of eight non-irradiated patients, and subnormal in all five irradiated patients. In the latter group the GH reserve was diminished when tested with GHRH. One patient from each group had a severe apnoea syndrome; in both cases there was no nocturnal GH increase. The percentage sleep stage 1 was lower for irradiated patients when compared with non-irradiated patients, but the 14 other sleep parameters did not differ. From this study we conclude that the physiological regulation of GH secretion is restored in surgically treated patients. Radiation therapy may lead to pituitary and hypothalamic damage, which could affect spontaneous GH secretion.

Acromegaly↗

Sebum excretion in acromegaly.

The sebum excretion rate (S.E.R.) was measured in 20 patients with acromegaly. Eleven were untreated at the time of the measurement and nine had previously undergone surgical hypophysectomy or had received pituitary irradiation by yttrium-90 or radiotherapy. In five patients the S.E.R. was measured before and after such treatment. The mean S.E.R. in the untreated acromegalics was much greater than in a normal population and decreased significantly after successful pituitary ablation. No significant decrease in mean S.E.R. occurred in the group of patients with a poor clinical response to ablation. The correlations between S.E.R. and log serum growth hormone, plasma 11-hydroxycorticosteroid levels, and heel-pad thickness were significant, but there was no significant correlation between S.E.R. and serum protein-bound iodine levels. This suggests that the changes in S.E.R. were due to pituitary ablation but could not necessarily be attributed solely to changes in growth hormone, thyroid-stimulating hormone, or adrenocorticotrophic hormone. The association between the clinical state of the acromegaly and the S.E.R. was better than the association between acromegaly and serum growth hormone. We conclude that the S.E.R. is a useful addition to the clinical and endocrinological data used in assessing acromegaly.

Acromegaly↗

Role of bilateral adrenalectomy in Cushing's disease.

Of 206 patients with Cushing's syndrome observed from 1975 through 1991, 144 (69.9%) had pituitary-dependent Cushing's disease. Of the 110 patients who underwent pituitary surgery, 31 (28%) developed an early recurrence and 23 patients (20%) had a late relapse 1 to 5 years after primary pituitary exploration. We performed a one- or two-step total bilateral adrenalectomy in 43 patients-9 men and 34 (79.4%) women, with an average age of 47.5 years (range 13-58 years). Thirty-three of these patients had already been treated by previous transsphenoidal surgery or alternatively by external pituitary irradiation over a period of 1 to 10 years prior to adrenal surgery. Thirty-one patients underwent adrenalectomy by a double lumbar access or left lumbar and right subcostal incisions. In our series of 55 operations, perioperative complications included two splenectomies and two hemorrhages (7.3%). The early mortality rate was 3.6% (two patients). Minor complications consisted of wound infection (13.5%), bronchopneumonia or pneumothorax (four cases) with a 7- to 12-day longer hospital stay. Nelson syndrome occurred in 6 of 41 patients (14.6%). We therefore believe that bilateral adrenalectomy does play a major role in the treatment of patients with pituitary-dependent Cushing's disease unsuccessfully managed by transphenoidal surgery. It represents the definitive therapy for those patients in whom hypophysectomy was not able to provide satisfactory control of the disease.

Adolescent↗

Tumour surveillance imaging in patients with extrapituitary tumours receiving growth hormone replacement.

OBJECTIVE: GH replacement is widely used in the management of patients with adult-onset (AO)-GH deficiency (GHD). In most cases, AO-GHD arises as a result of pituitary/peripituitary tumours and/or their treatment, but the effect of GH replacement on recurrence/regrowth of these tumours is unknown. The aim of this study was to examine the effect of GH replacement in a group of patients with primary tumours of the parasellar region, many of which (e.g. craniopharyngioma, glioma or germ cell tumours) might be anticipated to have a higher recurrence rate than secretory and nonsecretory anterior pituitary tumours. PATIENTS AND DESIGN: We report here our experience of prospective imaging in 50 consecutive patients (21 males; mean age 45.9 years) with nonanterior pituitary parasellar tumours treated with GH. All had severe GHD (peak serum GH 9 mU/l or less on dynamic testing) and were treated with an identical dose-titration regimen to maintain serum IGF-I concentrations between the median and upper end of the age-adjusted normal range. The primary diagnoses were: craniopharyngioma (28), germ cell tumour (8), arachnoid cyst (4), meningioma (4), glioma (4) and mensenchymal tumour (2). External pituitary irradiation had been given to 37 (74%) of patients. Measurements Surveillance imaging (magnetic resonance imaging (MRI) 70%, computed tomography (CT) 16%, both 14%) was performed at baseline (prior to GH), at 6--12 months, and then again yearly or as clinically indicated. Median follow-up was 36 months (range 7--129 months). All images were reviewed by the same radiologist. RESULTS: Four patients had an apparent increase in tumour volume but in only one patient was it considered necessary to abandon GH replacement. In two of the four cases marginal increases in cystic parasellar tumours were not progressive; and in the fourth case apparent recurrence of a suprasellar germ cell tumour was shown to be acellular fibrous tissue only on biopsy. In all other cases either the appearances were unchanged or the amount of tissue was reduced during long-term follow-up on GH. CONCLUSIONS: Overall, GH appears safe with respect to tumour recurrence over this time period in this patient group. Comparison with similar prospective series in patients not receiving GH replacement is desirable.

Adult↗

Final adult height and body mass index after cure of paediatric Cushing's disease.

OBJECTIVE: Linear growth data after cure of paediatric Cushing's disease (CD) have been reported infrequently. We evaluated final adult height (FH) and body mass index (BMI) in a cohort of paediatric patients treated successfully for CD. PATIENTS AND METHODS: Fourteen patients (10 male, age range 6.4-16.6 years) fulfilled the diagnostic criteria for CD. All had had transsphenoidal surgery (TSS), combined with pituitary irradiation (RT) (45 Gy in 25 fractions) in six. All were cured (post-TSS cortisol < 50 nmol/l or mean cortisol post-RT < 150 nmol/l). Subjects analysed had bone ages at diagnosis of < 15 'years' (male) and < 13 'years' (female). RESULTS: At diagnosis, height SDS was [mean (range)]-2.5 (-4.2 to -0.8) and body mass index (BMI) SDS +2.7 (0.8-5.1). Following cure, 13 patients had GH deficiency (peak GH < 20 mU/l) and were treated with hGH (+ GnRH analogue in four). Height SDS at FH (n = 10) or latest assessment (n = 4) was -1.3 (-3.9-0.2) and increased compared to diagnosis (P < 0.01). The difference between final or latest height SDS and target height SDS was -1.2 (-3.3-0.5), that is less (P < 0.01) than the difference between the height SDS at diagnosis and target height SDS of -2.4 (-3.9 to -0.5). At final height or latest assessment, BMI SDS was +1.7 (0.4-6.2), being decreased compared to diagnosis (P < 0.05) but greater than the normal population (P < 0.01). CONCLUSION: Catch-up growth was demonstrated in paediatric patients cured from CD, with the majority achieving FH within target height range. Early diagnosis and treatment of GH deficiency is recommended to achieve optimal long-term growth. Excess adiposity remains a potential long-term complication.

Adolescent↗

Relationship of bioassayable and immunoassayable plasma ACTH and cortisol concentrations in normal subjects and in patients with Cushing's disease.

Plasma ACTH and cortisol concentrations were determined at 5-min intervals over a 3- or 4-h sampling period in 2 normal subjects. Time spans studied were 10:00 AM-1:00 PM, 4:00 PM-8:00 PM, 8:00 PM-11:00 PM, and 4:00 AM-8:00 AM. Similar sampling for 3 h, (onset 9:00-9:30 AM) was performed on 4 patients with Cushing's disease, 3 untreated and 1 in remission following pituitary irradiation. Two of these patients were studied on 2 separate occasions. Plasma ACTH was determined by both immunoassay (I) and bioassay (B). Although in general, these studies demonstrated significant correlation between I-ACTH or B-ACTH concentrations and those of plasma cortisol, a striking finding in both subject categories was the presence of 30- to 50-min episodes during which marked rises in both I- and B-ACTH concentrations occurred without concomittant, or markedly diminished, increments in plasma cortisol concentrations. This could not be explained by biological inactivity of the ACTH, since a highly significant correlation was present between I- and B-ACTH concentrations at all times; r values ranged between 0.86 and 0.98 for normal subjects, and 0.76 and 0.96 for patients with Cushing's disease. The lack of correlation in these episodes also does not appear to be secondary to an 11-beta-hydroxylase block, differences in the rate of change of plasma ACTH concentrations, lack of adrenal "priming" by prior ACTH or incapacity of the adrenal gland to further increase secretion. I/B ACTH ratios were similar in the normal subjects (1.42-1.64) and in the patients with Cushing's disease (1.27-1.47). "Apparent" ACTH half lives calculated from "peaks" of ACTH secretion were 7-12 min for I-ACTH and 3-9 min for B-ACTH in the normal subjects; and 9-13 min and 7-9 min respectively, in the patients with Cushing's disease. Mean plasma ACTH I-and B-concentrations at comparable time periods were higher in patients with active Cushing's disease than in normal subjects. These studies also indicate that in Cushing's disease, the abnormality present resides in ACTH regulatory mechanisms, not in the nature of the ACTH secreted. Approximation of the total amount of immunoassayable ACTH secreted in one normal subject over a 24-h period yielded a value of 73 mug. Total mug/h secreted in the 2 normal subjects were highest in the hour preceding awakening (6:30-7:30 AM; 12.9 and 12.2 mug/h); were 5.3 and 4.0 mug/h between 10:00-11:00 AM, and 1.4 and 1.7 mug/h between 9:00-10:00 PM. In the 3 patients with clinically active Cushing's disease, apparent ACTH secretion between 10:00-11:00 AM varied from 19.2-34.3 mug/h, the magnitude of such secretion being positively correlated with the extent of increased adrenal cortical activity present.

Adrenocorticotropic Hormone↗

Pharmacologic erection with intracavernosal injection for men with sexual dysfunction following irradiation: a preliminary report.

Impotence is a possible consequence of treatment of pituitary adenomas and prostatic carcinomas. Following pituitary irradiation, the effect has been attributed to decreased gonadotrophins, while a variety of mechanisms, primarily vascular and neurogenic, have been proposed to explain the impotence following irradiation of prostatic carcinomas. Men with impotence of any etiology have been entered on a program to evaluate prospectively the efficacy of intracavernosal injection of vasoactive compounds in producing a satisfactory erection with pharmacologic means. Ten of these men had developed impotence following therapy for pituitary adenomas (2) or prostatic carcinomas (8). Test doses of 0.1 to 0.5 ml of a phentolamine (1 mg/ml) and papaverine (30 mg/ml) mixture were used; the dose was titrated to produce an erection deemed sufficient for vaginal penetration. All patients achieved a satisfactory response (i.e., tumescence and rigidity) lasting 10 minutes to 3 hours. Seven patients have continued in the pharmacologic erection program, with six patients functioning normally, and the remaining patient noting decreased tumescence after 18 months of treatment, but adequate erections are maintained with supplemental penile ring. Two patients have discontinued intracavernosal injections due to inconvenience, and one patient was lost to follow-up. Recent substitution of prostaglandin E1 (PGE1) has produced similar results and has replaced the phentolamine-papaverine combination. These preliminary results indicate that pharmacologic erection can be achieved in patients with impotence related to the treatment of pituitary and prostatic neoplasms and represents a reasonable alternative to implanted penile prostheses.

Adenoma↗

Pituitary disorders. Drug treatment options.

Pituitary diseases are relatively common entities in the general population. They include pituitary adenomas and hypopituitarism. Pituitary tumours can cause symptoms of mass effect and hormonal hypersecretion that can be reversed with surgical resection or debulking of the adenoma, radiotherapy, or medical treatment. Transsphenoidal adenomectomy is the treatment of choice for acromegaly, Cushing's disease, gonadotropin-secreting tumours; and thyrotropin (TSH)-secreting adenomas. Pituitary irradiation and medical therapy are secondary options. Conversely, medical treatment is the primary choice for prolactinomas. Dopamine agonists are very effective in the treatment of prolactin (PRL)-secreting tumours, with rates of control as high as 80 to 90% for microprolactinomas (< 10 mm) and 60 to 75% for macroprolactinomas (> or = 10 mm). Somatostatin analogues have also shown efficacy in patients with acromegaly who have not responded to surgery or in patients with TSH-secreting adenomas who have not improved with surgery and radiotherapy. In patients with Cushing's disease, who are not cured surgically or who relapse after pituitary adenomectomy and irradiation, steroidogenic inhibitors can be an efficient method of controlling the hypercortisolism. Pituitary insufficiency is the partial or complete loss of the anterior hypophyseal function, which is due to hypothalamic or pituitary disease. Although the classic sequence of loss of pituitary secretion is growth hormone (GH), gonadotropins, TSH, and corticotropin (ACTH), the order to begin the replacement therapy of the deficient hormone(s) is cortisol, thyroxine, androgens/estrogens and, if necessary, GH. There are multiple preparations that can be used to achieve clinical and biochemical improvement. In general, the hormone replacement therapy is lifelong.

Adenoma↗

Risk factors for brain infarction in patients with Cushing's disease. Case reports.

Two women aged 51 and 52 years old, respectively, developed a brain infarction before and after undergoing treatment for Cushing's disease. A biochemical remission was obtained more than ten years after the onset of signs or symptoms of Cushing's disease. The arteriosclerotic changes of the cerebral vessels progressed even during replacement therapy for posttreatment hypopituitarism after they underwent either ablative surgery or radiotherapy. One patient, who showed the signs of Nelson's syndrome, demonstrated severe progressive cerebrovascular sclerotic changes, especially around the irradiated site. It is thus suggested that hypercortisolemia, external pituitary irradiation, and posttreatment hypopituitarism may be risk factors for brain infarction. The early diagnosis and adequate treatment are therefore important to prevent cerebrovascular complications in patients with Cushing's disease.

Cerebral Infarction↗

Effectiveness of long-acting octreotide in suppressing hormonogenesis and tumor growth in thyrotropin-secreting pituitary adenomas: report of two cases.

BACKGROUND: The subcutaneous (s.c.) administration of somatostatin analogs, such as octreotide acetate (SMS) and lanreotide, in patients with thyrotropin (TSH)-secreting pituitary adenomas (TSPA's)--thyrotropinomas with residual tumor after initial surgical therapy is effective in controlling hyperthyroidism, as well as curtailing tumor growth in the majority of patients. Long-acting preparations of the above agents, i.e. SMS-LAR and lanreotide-SR, have been synthesized and can be administered as depot injections intramuscularly (i.m.) at intervals of several weeks. Recent studies have reported on preliminary data regarding the use of such preparations in patients with TSPA's. MATERIALS AND METHODS: We present two cases of TSPA's with residual tumor following transsphenoidal adenomectomy. Neither of the two patients underwent external beam pituitary irradiation. The presence and extent of tumoral TSH hypersecretion was assessed by standard biochemical and dynamic endocrine testing, while tumor size was evaluated by conventional radiographic techniques. RESULTS: In both patients, TSH secretion was effectively suppressed by SMS-LAR. Moreover, administration of this compound halted further tumor growth, as well as resulted in improved patient comfort, for 12 and 10 months respectively. CONCLUSION: Our date corroborate earlier reports on the usefulness of SMS-LAR in the medical management of patients with TSPA's who have residual disease after initial pituitary surgery and/or irradiation.

Adenoma↗

Cyproheptadine treatment in Cushing's disease.

Cyproheptadine, a nonselective 5-hydroxytryptamine receptor blocking agent, reduces ACTH and beta-endorphin secretion from the ACTH-producing tumors. A 35-year-old female suffering from Cushing's disease due to microadenoma of the pituitary gland has been followed since the age of 15. Subtotal adrenalectomy followed by total adrenalectomy, pituitary irradiation, and transsphenoidal hypophysectomy, combined with second radiotherapy of the pituitary, were unsuccessful in achieving remission of the disease. Remission was achieved with cyproheptadine up to a dosage of 24 mg/day. Every attempt to discontinue cyproheptadine treatment was accompanied by recurrence of the disease. This is the first case of Cushing's disease in which cyproheptadine treatment has been the only efficacious therapy for a period of 11 yr. Cyproheptadine may be an alternative long-term therapy for Cushing's disease when other methods of treatment fail.

Adenoma↗

Malignant evolution of an ACTH-producing pituitary tumor treated with intrasellar implantation of 90Y. Case report and review of the literature.

A case of pituitary carcinoma is here presented, together with a review of the 25 cases so far reported in the literature. After a long-standing history of Cushing's disease, treated with interstitial pituitary irradiation and total adrenalectomy, Nelson's syndrome developed due to a pituitary neoplasm that finally spread through the subarachnoidal space, bringing the patient to death. The possible long-term role of surgery and radiotherapy in switching an aggressive behavior is also discussed.

Adrenalectomy↗

Adrenocorticotrophin (ACTH) deficiency undetected by standard dynamic tests of the hypothalamic-pituitary-adrenal axis.

Six patients (four females, two males; aged 18-65 years), previously treated by external pituitary irradiation (2000-4000 cGY in 8-15 fractions over 10-20 days) for pituitary tumours, presented with the symptoms of excessive and inappropriate tiredness suggestive of ACTH deficiency, despite a normal peak cortisol response to an insulin tolerance test (four cases) or to a glucagon stimulation test (two cases). These six patients were found to have significantly lower mean 24 h urinary free cortisol levels (100 +/- 40 nmol; mean +/- SD) compared with the mean value of 31 normal controls (210 +/- 70.8 nmol; P less than 0.01). In addition serum cortisol profiles based on a series of four timed samples between 0900-2300 h were subnormal (mean 130 nmol/l) in comparison with profiles obtained from 12 normal controls (mean 270 nmol/l) (P less than 0.001). Glucocorticoid replacement therapy promptly abolished their symptoms. These results suggest that a discordance between ACTH secretion under basal circumstances and ACTH response to pharmacological tests may exist in patients with ACTH deficiency. We speculate that defective endogenous corticotrophin-releasing hormone (CRF) secretion, due to radiation-induced damage at hypothalamic level, is one cause of this phenomenon.

Adolescent↗