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At least 55 records · Page 3Linked to original sources
PubMed1997

Pituitary irradiation is ineffective in normalizing plasma insulin-like growth factor I in patients with acromegaly.

Pituitary irradiation suppresses GH hypersecretion in patients with acromegaly. Within 10 yr after radiotherapy, up to 80% of patients achieve plasma GH levels below 5 micrograms/L. Whether this is sufficient to normalize plasma insulin-like growth factor I (IGF-I) levels, is unknown. We examined the effect of radiotherapy on plasma IGF-I concentrations in patients with acromegaly. We reviewed hospital charts of 140 patients with acromegaly seen in our institution between 1975 and 1996. Data on plasma GH and IGF-I were extracted and tabulated longitudinally together with the information about the concomitant medical therapy. We included data from the patients who received radiotherapy as a part of their treatment and whose IGF-I was monitored for more than 1 yr afterward. To avoid the potential bias, the data for patients who were referred to us for medical therapy, having failed radiation elsewhere, were excluded. A total of 38 datasets were submitted for the final analysis. The average follow-up was 6.8 +/- 0.8 yr (range, 1-19). Only 2 patients achieved age- and sex-adjusted normal IGF-I levels while off medical therapy. Noncured patients had a mean plasma GH level of 4.6 +/- 1.1 micrograms/L but still elevated plasma IGF-I levels (219 +/- 26% of the upper normal limit) at the last follow-up visit. A random GH concentration below 1.5 micrograms/L was associated with a pathologically high plasma IGF-I concentration in 43% of instances. Radiotherapy appears to be ineffective in normalizing plasma IGF-I levels in acromegaly. A multicenter study to reevaluate the future use of this modality in patients with acromegaly is warranted.

Acromegaly↗
PubMed1978

Hypopituitarism following pituitary irradiation for acromegaly.

Endocrine evaluation is reported in 8 acromegalic patients who received 5,500 rad to the pituitary from a linear accelerator. There was a mean decrease in hGH levels of 72%. Plasma testosterone levels were low in 1 of the 6 male patients prior to pituitary irradiation and were below normal in all male patients on the final evaluation (3.1 +/- 0.2 SD years postirradiation). Deficiency of TSH secretion developed in 2 patients following irradiation. This rather high incidence of postirradiation partial hypopituitarism was not anticipated, and is thought to be related to radiation necrosis of the normal pituitary tissue which surrounds the adenoma.

Acromegaly↗
PubMed1978

Unilateral adrenalectomy and pituitary irradiation in the treatment of ACTH-dependent Cushing's disease in children and adolescents.

In four juvenile patients with Cushing's disease, the therapeutic approach used was unilateral adrenalectomy followed by irradiation of the pituitary. The follow-up time of these patients has ranged from 1.5 to 10 years. All four are clinically well. Concentrations of adrenal steroids are within normal limits and they require no additional medication. It is felt that this method gives young patients the chance for normal growth and pubertal development as well as a normal social life, so important in the stressful adolescent years, thus avoiding the handicap incurred by bilateral adrenalectomy and the consequent requirement for continuous substitution therapy.

Adolescent↗
PubMed1989

Megavoltage pituitary irradiation in the management of Cushing's disease and Nelson's syndrome: long-term follow-up.

We report the long-term follow-up of the clinical and biochemical effects of megavoltage pituitary irradiation (radiotherapy; RT), administered as primary or secondary therapy, for pituitary Cushing's disease and Nelson's syndrome in 52 patients. Irradiation was administered, from a 4-15 MeV linear accelerator, via a three-field technique (two lateral, one frontal), to a total dose of 4500 cGy (rad) in 25 fractions over 35 days. Twenty-one patients received RT as primary ablative therapy for Cushing's disease and were under follow-up 5.8 to 15.5 years later (median 9.5 years). All were initially treated with metyrapone to induce normal mean plasma cortisol levels, and all achieved clinical remission on this therapy. At latest follow-up, 12 (57%) are off all therapy, in clinical remission, with a normal mean cortisol through the day; however, only two show completely normal plasma cortisol responses to dynamic testing; four remain on medical therapy with metyrapone or op'DDD and all have required a steady dose reduction accompanied by falling plasma ACTH levels; five have required alternative therapy with bilateral adrenalectomy and/or transsphenoidal hypophysectomy. Fifteen patients received RT for Nelson's syndrome, developing after bilateral adrenalectomy, and have been followed up for 1.5 to 17.3 years (median 9.6 years). Fourteen patients showed progressive depigmentation, shrinkage of the pituitary adenoma and fall in plasma ACTH levels to 1-72% (median 16%) of the pre-RT basal value. In the remaining patient an initial fall in plasma ACTH was followed by tumour enlargement at 6 years, leading to death at 11 years after RT. Of the remaining patients, results are assessed in nine who received RT after unsuccessful transsphenoidal surgery, three after transfrontal surgery for aggressive macroadenomas, and four prophylactically after bilateral adrenalectomy. Radiotherapy remains a valuable second-line therapy for Cushing's disease and its complications.

Adolescent↗
PubMed1998

Normal final height and apparent cure after pituitary irradiation for Cushing's disease in childhood: long-term follow-up of anterior pituitary function.

Pituitary-dependent Cushing's syndrome is rare in childhood. Two patients are reported who had unsuccessful transsphenoidal microadenomectomy and therefore underwent pituitary radiotherapy. In both patients there was progressive normalization of hypothalamo-pituitary-adrenal function and at 8 and 10 years after radiotherapy their Cushing's syndrome remained in remission clinically and biochemically. Most importantly, they have both achieved adult heights within their respective expected ranges with close clinical observation and replacement growth hormone therapy. Thyroid and gonadal function is normal and neither patient requires any other hormone replacement therapy. Pituitary radiotherapy is thus a safe, effective and well tolerated second-line therapy for paediatric Cushing's disease. Collaboration between the paediatric and adult departments and an experienced radiotherapist contributed to the successful outcome of these two patients.

Adolescent↗
PubMedDate not supplied

Hypercalcemia and local production of parathyroid hormone-related protein by a perisellar rhabdomyosarcoma after remote pituitary irradiation.

OBJECTIVE: To describe a case of metastatic rhabdomyosarcoma originating from the sphenoid sinus in a patient previously treated with conventional irradiation for a prolactinoma, presenting as hypercalcemia in the setting of a normal level of serum parathyroid hormone-related protein (PTHrP). METHODS: We report the case of a patient who underwent remote pituitary irradiation for a prolactinoma and then presented decades later with hypercalcemia of unknown cause. His clinical course, the initial biochemical and radiologic investigations, and the results of examination of pathology specimens are reviewed. RESULTS: The patient was found to have a mass in the sphenoid sinus. The pathologic features were consistent with alveolar rhabdomyosarcoma. Although he had a normal serum PTHrP level, staining of his tumor with an antibody against PTHrP revealed local production of PTHrP at the tumor margins. His bone marrow biopsy specimen showed 100% involvement with rhabdomyosarcoma. CONCLUSION: PTHrP staining of pathology specimens might explain hypercalcemia of undetermined cause in patients with a known malignant lesion, in whom elevated serum PTHrP levels cannot be demonstrated.

Aged↗
PubMed1990

Low-dose pituitary irradiation for acromegaly.

External radiotherapy has been used as primary treatment for acromegaly in 29 patients and in combination with surgery in 41 patients in whom growth hormone levels remained elevated postoperatively. Fourteen further patients who did not receive radiotherapy have also been studied, four of whom had undergone surgical treatment. Radiotherapy schedules consisted of 20 Gy in eight fractions over 11 days (n = 23) or 35-40 Gy in 15 fractions over 21 days (n = 47). Growth hormone hypersecretion was either unchanged or increased with time in non-irradiated patients. In those patients who underwent radiotherapy, the likelihood of the mean GH level during GTT falling to less than 5 mU/l was unaffected by the total dose of radiation administered. However, patients with a pre-radiotherapy GH level of less than 30 mU/l showed a significantly increased probability of achieving a post- radiotherapy GH level less than 5 mU/l (P = 0.002). Previous surgery, initial serum prolactin and the age or sex of the patient did not predict the successful outcome of radiotherapy. In view of the known dose dependency of radiation-induced hypopituitarism, lower radiation dose schedules (20 Gy; eight fractions in 11 days) can be used in acromegaly with some benefit, especially in younger patients. However, all patients should undergo operative removal of as much GH-secreting tissue as possible, in order to lower GH levels and increase the probability of achieving a cure following radiotherapy.

Acromegaly↗
PubMed1986

Treatment of Cushing's disease in childhood and adolescence by stereotactic pituitary irradiation.

Eight children with Cushing's disease aged 6-18 years were treated with external radiation to the pituitary gland using 60Co gamma radiation given with stereotactic technique. The dose given varied between 50 and 70 Gy. The observation time was 2.6 to 6.75 years. Seven children had a clinical remission with normal urinary cortisol excretion. One child had insufficient effect of two irradiations and underwent bilateral adrenalectomy. In the patients in remission the growth velocity increased during the first year after treatment but growth retardation occurred again during the second year. Insufficient growth hormone secretion was demonstrated in all subjects. Two patients were given thyroxine substitution and three showed evidence for secondary hypogonadism. In conclusion, stereotactic pituitary irradiation was effective in normalizing the excessive glucocorticoid production in children with Cushing's disease. However, with the doses used, it was not possible to maintain a normal anterior pituitary function.

Adolescent↗
PubMed1977

Post-irradiation pituitary sarcoma.

A fibrosarcoma developed in the pituitary fossa of a patient who had been irradiated 13 years previously for treatment of pituitary adenoma. The tumor was a large aggressively growing spindle cell neoplasm which eroded adjacent structures, causing increased intracranial pressure, and eventual cerebellar tonsillar herniation. In common with previously described post-irradiation sarcoma of the pituitary, this lesion developed in the path of irradiation after a long latent period, did not metastasize, and contained histologically recognizable benign appearing pituitary adenoma interspersed among the spindle cell tumor. The dose of radiation (5000 rads) also lay within the range associated with sarcomatous transformation.

Aged↗