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Prolactin and placental hormone levels during pregnancy in prolactinomas.

Prolactin (PRL) and the placental hormones, estradiol (E2), estriol (E3), progesterone (PG), chorionic gonadotropin (HCG), and placental lactogen (HPL) were serially measured throughout pregnancy and early postpartum in three patients with prolactinomas in whom pregnancy was achieved by one of the three modalities of treatment: bromocriptine administration (patient I), irradiation of the pituitary (patient II), and human gonadotropin administration after excision of the adenoma (patient III). It was found that PRL in patient I reached the high pretreatment levels in the 2nd month of pregnancy and increased to further abnormal concentrations in the last 2 months, but fell at the onset of labor 1 week after an episode of severe headache. The PRL changes in this patient were attributed successively to tumor expansion and apoplexy. In patient II PRL decreased after irradiation, but was not normalized. During pregnancy it remained moderately increased presenting minor fluctuations. The third patient with postoperative GH and TSH pituitary insufficiency had low pretreatment PRL levels which remained practically unchanged throughout pregnancy. The two last patients gave birth to identical twins. The placental hormones were found normal in all three patients but E2 and PG were relatively increased during the last weeks of pregnancy in the twin pregnancies. Amniotic fluid and umbilical cord PRL and E2 concentrations were normal. The patients presented agalactia and suckling did not induce a PRL increase. We conclude that a) serial PRL measurements during pregnancy reflect the changes occurring in the prolactinomas and are essential in monitoring the patients bearing these tumors; b) maternal hyperprolactinemia or failure of PRL to increase during pregnancy do not influence either the secretion of placental hormones or PRL concentration in amniotic fluid and the newborn; and c) hyperprolactinemia during pregnancy is of maternal pituitary origin.

Adenoma↗

Pituitary enlargement secondary to hypothyroidism associated with sublingual thyroid gland.

Two patients with sublingual thyroid glands and hypothyroidism since childhood are described. Because of enlargement of the sella turcica both were erroneously diagnosed as having primary pituitary tumors resulting in secondary hypothyroidism. One of the patients was even treated with pituitary gland irradiation. Following substitution thyroid therapy, thyroid-stimulating hormone (TSH) levels promptly returned to normal. Ectopic thyroid glands, which are often incapable of adequate hormonogenesis, may cause secondary pituitary enlargement and lead to the suspicion of a pituitary adenoma. The correct diagnosis can easily be established by measuring serum TSH levels, which are elevated in the former condition.

Adult↗

[Clinical manifestations of the local effect of protons with an energy of 1000 Mev following irradiation of the hypophysis (experimental)].

In order to study the clinical picture due to inrradiation of the hypophysis by protons with an energy of 1000 Mev with the use of a pendulum technique, the authors examined 30 dogs including 27 with an irradiated hypophysis and 3 control animals during 2 years. The results were verified in autopsies and in histological studies. These examinations demonstrated frequent general cerebral symptoms, focal neurological and hypophysis-endocrinological symptoms as well as frequent lesions of the cranial nerves, epileptic seizures and nonsymptomatic focal brain necrosis. It was also possible to demonstrate a correlation of the clinical traits with the dosage of the irradiation and the time past after irradiation. The report contains corrections for using these data on humans.

Animals↗

Absence of irradiation induced ischaemic temporal lobe damage in patients with pituitary tumours.

This study was undertaken to confirm the belief that modern day external beam radiotherapy for patients with pituitary tumours should not be associated with any ischaemic temporal lobe damage. Using the oxygen-15 steady state inhalation technique and positron emission tomography regional temporal lobe blood flow, oxygen extraction fraction and oxygen utilisation were measured in 10 normal volunteers and 11 patients with pituitary tumours treated by irradiation. The patients were studied between 1 and 10.9 years after radiotherapy. We found that temporal lobe oxygen utilisation in the irradiated group (mean 2.11 +/- 0.23 ml of O2/100 ml tissue/min) did not differ from the normal group (mean 2.13 +/- 0.26 ml of O2/100 ml tissue/min). This suggests that total doses of between 35 and 56 Gy, delivered in fractions of less than 2 Gy, can be given to a pituitary tumour without demonstrable damage to normal temporal lobe.

Adult↗

Pathological changes after radiotherapy for primary pituitary carcinoma: a case report.

Pituitary carcinomas are extremely rare. The definition, diagnosis, therapy, and prognosis are controversial. So far, to our knowledge, there has been no report regarding pathological changes after radiotherapy for primary pituitary carcinoma. We reported a single case of a presumed prolactin staining pituitary carcinoma. We defined carcinoma by premorbid intracranial dissemination of the tumor. There were no proven extracranial metastases. The tumor was silent on PET scanning. The patient received external beam radiotherapy alone as primary therapy. Post-irradiation histology revealed that necrotic tissue made up approximately more than half. Tumor had viable cells. Probably approximately three-fifth of tumor cells were without alteration and approximately two-fifth were with degeneration. We confirmed that necrosis but no apoptosis were coexistent in the cells post irradiation for pituitary carcinoma.

Adenocarcinoma↗

Treatment of acromegaly by external irradiation.

Despite the place of hypophysectomy as the primary treatment in acromegaly, external radiotherapy maintains a role as a relatively slow but effective therapy for inadequately treated patients or those unsuitable for operation. Over the last 25 years our radiotherapy regimen has differed from the published series in that we give a larger dose per fraction, with fewer treatments. We have analysed the efficacy and side-effects of this regimen in 27 subjects with acromegaly. Growth hormone levels have fallen by, on average, 27% per year in the first five years, 83% of subjects achieving a basal growth hormone of less than 10 mU/l. The acute and chronic side-effects of irradiation are discussed, including the relevance of estimates of biological potency, for example the Time Dose Fraction (TDF). One patient suffered visual loss that was most likely to be secondary to the radiotherapy. We also report the histological appearances of the pituitary fossa in five subjects previously treated with radiotherapy.

Acromegaly↗

The effect of single-dose radiation on cell survival and growth hormone secretion by rat anterior pituitary cells.

Cranial irradiation has been shown to impair growth hormone secretion in children. In this study a cell culture of dispersed rat anterior pituitary cells was exposed to single doses of radiation in the range of 100-1500 rad: Survival curves were obtained for the different anterior pituitary cell lines, and growth hormone secretion was measured in the tissue culture medium. Both survival and growth hormone secretion curves showed an initial shoulder in the range of 0-300 rad, followed by a decline between 300-750 rad. It is concluded that growth hormone secreting acidophilic pituicytes are sensitive to radiation at single doses greater than 300 rad.

Animals↗

Polyostotic fibrous dysplasia and acromegaly.

A review of the recent orthopaedic literature reveals little information on the endocrinopathic associations of polyostotic fibrous dysplasia. This article illustrates the need for endocrinologic evaluations at both initial diagnosis and at follow-up examinations. Two patients with polyostotic fibrous dysplasia and acromegaly are presented. In both cases, diagnosis was made by endocrinologic and radiographic evaluations, including computed tomography (CT) scan of the skull. One patient had pituitary macroadenoma, and the other had pituitary microadenoma. Irradiation therapy was performed successfully in both patients without any complications.

Acromegaly↗

Histological changes in the hypofunctional pituitary gland following conventional radiotherapy for adenoma.

AIMS: Although delayed hypopituitarism is a common complication of conventional radiotherapy of sellar tumours, histological changes that may account for it have been rarely reported. To elucidate the changes, hypofunctional pituitary glands following irradiation were studied. METHODS AND RESULTS: Two pituitary glands obtained at autopsy from patients who had been irradiated for adenoma and exhibited hypopituitarism were examined. In both cases diffuse fibrosis was observed in the adenohypophysis, whereas the neurohypophysis remained unchanged. Immunohistochemistry showed that stellate-shaped S100 protein-positive cells were increased in number and distributed among the endocrine cells. Some irradiated endocrine cells showed dense granular immunoreactivity for mitochondrial protein, cytochrome oxidase and manganese-superoxide dismutase. In addition to faint reactivity with anti-cytokeratin 8, 18 antibody, many cells were densely positive with anti-cytokeratin 1, 5, 10, 14 antibody. CONCLUSIONS: These results indicate that radiation- induced fibrosis is associated with an increased number of folliculo-stellate cells and the presence of metabolic dysfunctional mitochondria resembling mitochondria in oncocytes. Squamous metaplasia in the irradiated endocrine cells was also noted. Various intracellular changes may participate in delayed pituitary hypofunction following radiotherapy.

Adenoma↗

Long-term effects on external radiation on the pituitary and thyroid glands.

Chronic damage following external irradiation of the normal pituitary and thyroid glands, delivered incidentally during radiotherapy of neoplasms of the head and neck may be more common than has been appreciated in the past. A case of a child who developed pituitary dwarfism 5 1/2 years after radiation therapy has been delivered for an embryonal rhabdomyosarcoma of the naso-pharynx is described. A review of similar cases from the literature is presented. Likewise, external irradiation of the normal thyroid gland produces a spectrum of radiation-induced syndromes. Clinical damage to the pituitary and thyroid glands is usually manifested months to years after treatment and is preceded by a long subclinical phase. A careful exclusion of these glands from radiation treatment fields is recommended whenever possible. An early detection of endocrine function abnormalities in patients receiving radiation to these glands is desirable, since appropriate treatment may prevent the deleterious effects of external irradiation of the pituitary and thyroid glands.

Adult↗

[Dosimetric basis of mean fractionation in the irradiation of bone metastases in breast cancer].

Proceeding from the drawing of maps with biologically isoeffective percentage doses the authors provide a dosimetric substantiation of gamma-beam irradiation of different parts of the bony skeleton using the following irradiation scheme: a single dose of 4 Gy, 5-6 fractions daily. It has been shown that to choose a therapeutic plan in the utilization of a nonstandard scheme of fractionation, the calculation of the TDF factor by Orton's tables is safe and illustrative. By way of example are given maps of isoeffective doses used in the irradiation of bone metastases in breast cancer patients with metastases to different parts of the skeleton.

Bone Neoplasms↗