Lymphocytic adenohypophysitis simulating a pituitary adenoma in a pregnant woman

The lymphocytic hypophysitis, appearing in women during the third trimester of pregnancy or early post-partum period, is a rare cause of hypopituitarism and pituitary enlargement. A 39 year-old woman presented in the 37th week of pregnancy with bilateral heteronymous quadrantanopsia, CT indicative of tumorous mass and symptoms of hypopituitarism with decreased thyroid hormone and thyrotrophin levels, and low normal level of cortisol. After the birth of a healthy male child the patient breastfed for 10 days, sight disturbances disappeared, but amenorrhea persisted. Upon admittance the visual field showed no abnormalities. MR of the sellar region confirmed previous CT findings. Endocrinological testing confirmed secondary hypothyroidism and cortisol deficiency, normal levels of prolactin with satisfactory reaction to thyroliberin. Histology showed mononuclear infiltration, and immunohistochemistry revealed T-cells (CD3) at the borders, and B-cells (CD20) in the follicular center. Due to enlargement of the pituitary associated with hypopituitarism, an incorrect diagnosis of a tumor could be made.     

Effects of activin A and somatostatin on intact FSH secretion and intracellular Ca2+ concentration in human FSH-secreting pituitary adenoma cells.

Activin A stimulated synthesis and secretion of intact FSH in dispersed human FSH-secreting adenoma cells. Significant stimulation was observed after 24 hr. Activin A caused an increase in Ca2+ concentration ([Ca2+]i). This response occurred soon after the activin A action. These effects were blocked in Ca(2+)-deficient medium and by nitrendipine (5 microM). Somatostatin inhibited the activin A-induced intact FSH secretion and the [Ca2+]i response. These findings indicated that Ca2+ influx through voltage-gated Ca2+ channel was involved in the activin A induced synthesis and secretion of intact FSH.     

Thyrotropin-secreting pituitary adenoma: a case report.

We report a 44-year-old male with a thyrotropin (TSH)-secreting pituitary adenoma. Based serum free triiodothyronine (FT3, 12.1 pmol/l) and free thyroxine (FT4, 28 pmol/l) were increased with normal basal TSH (3.1 mU/l). There was impaired TSH response to thyrotropin releasing hormone (TRH) test. Serum TSH was suppressed to 59% of the basal level after oral administration of 1.4 mg 3,3'-5-triiodothyroacetic acid (triac), whereas no suppression was observed after 75 micrograms daily administration of triiodothyronine (T3). Serum concentrations of alpha-subunit of TSH (TSH-alpha) and TSH-alpha/TSH molar ratio were high, being 1.95 micrograms/l, and 4.4, respectively. Pituitary CT and MRI scan showed the presence of a macroadenoma in the anterior lobe of the pituitary gland. Histopathology of the excised pituitary confirmed the diagnosis of a TSH-producing adenoma. A positive correlation between TSH and FT3 (r = 0.66, P less than 0.01) or FT4 (r = 0.54, P less than 0.01) was observed in serial sera obtained before and after operation.     

Cytology of a chromophobe pituitary adenoma. A case report

A pituitary tumor with suprasellar and extrasellar extension was investigated by means of the squash-smear cytologic technique. The dominant cell type was large, round to oval cells, with pale-staining, finely granular cytoplasm. The nuclei of these cells often contained single or multiple inclusions of uncertain nature. There also were cells with eosinophilic cytoplasm, usually collected in small nests. Hyperchromatic "naked" nuclei, in various shapes, were immersed in a homogeneous, faintly staining ground substance. Mitotic figures were detected easily. Cytology of these combined cell types allowed the intraoperative diagnosis of a rather pleomorphic pituitary adenoma.     

Letter: Spontaneous pelvic thrombosis in the postmenopausal woman.

An epidemic of rubella reached its peak in the Atlantic provinces in 1974, subsiding in early 1975. With the exception of Quebec the remainder of Canada showed a reverse trend, with a large increase in the numbers of cases reported in the first 41/2 months of 1975. The Halifax virus laboratory reported 106 serologically proven cases of rubella in 1974, 44 of them in pregnant women. In the aftermath of the epidemic many infants were born with the congenital rubella syndrome (CRS). A study carried out from Sept. 1, 1974 through Apr. 30, 1975 showed an 80% correlation between clinical diagnosis and the presence of rubella-specific IgM antibodies in 35 of these infants. Of the 23 infants in whom the diagnosis of CRS was made by laboratory or clinical findings or both, laboratory criteria were met in 20 (87.0%), clinical criteria in 19 (82.6%) and both laboratory and clinical criteria in 16 (69.6%).     

Predicting maximal strength in trained postmenopausal woman

The purpose of this study was to present an equation that accurately predicts 1 repetition maximum (RM) over a wide range of repetitions to fatigue (RTF) for 4 different machine resistance exercises in postmenopausal women. Seventy trained women (age = 57.4 +/- 3.1 years) performed maximal and submaximal repetitions on leg press, bench press, rowing, and leg adduction machines at the conclusion of a 2-year training program. Maximal repetitions were performed on each exercise in the following ranges: 3-5RM, 6-10RM, 11-15RM, and 16-20RM. Special regard was taken to maintain the identical execution of each test (i.e., range of motion, starting angle, speed of movement). One cubic polynomial (w(i) [0.988-0.0000584 r(i)(3) + 0.00190 r(i)(2) + 0.0104 r(i),] where w(i) is the load of measurement I, and r(i) is the number of repetitions) accurately predicted 1RM from RTF with mean absolute differences between actual 1RM and predicted 1RM for the 4 exercises of 1.5-3.1% and with coefficients of variation of <3.3%. Equation accuracy was independent of the exercise type or the number of RTF. Thus, this study supported the validity of RTF to adequately estimate 1RM over a wide range of repetitions and within different exercises in trained, older female subjects.     

A reference map of a human pituitary adenoma proteome

In order to compare the proteomes from different cell types of pituitary adenomas for our long-term goal to clarify the molecular mechanisms that participate in the formation of pituitary adenoma, and to detect any tumor-related marker for an "early-stage" diagnosis, the two-dimensional gel electrophoresis (2-DE) reference map of a pituitary adenoma tissue proteome is described here. A vertical, two-dimensional (2-D) polyacrylamide gel electrophoresis system and PDQuest image analysis software have been used to provide a high level of between-gel reproducibility and to accurately array each protein expressed in a pituitary adenoma tissue. Mass spectrometry (matrix-assisted laser desorption/ionization-time of flight MALDI-TOF and liquid chromatography-electrospray ionization-quadrupole-ion trap LC-ESI-Q-IT) and protein databases were used to characterize each protein in the 2-D gel. The results demonstrate that a good reproducibility of the 2-D gel pattern was attained. The position deviation of matched spots among four 2-D gels was 1.95 +/- 0.45 mm in the isoelectric focusing direction, and 1.70 +/- 0.53 mm in the sodium dodecyl sulfate-polyacrylamide gel electrophoresis direction. A total of ca. 1000 protein spots were separated by 2-DE, and 135 protein spots that represent 111 proteins were characterized with mass spectrometry (96 spots for MALDI-TOF, 39 spots for LC-ESI-Q-IT). The characterized proteins include pituitary hormones, cellular signals, enzymes, cellular-defense proteins, cell-structure proteins, transport proteins, etc. Those proteins were located in the cytoplasmic, cellular membrane, mitochondrial, endoplasmic reticulum, nuclear, ribonucleosome, extracellular fractions, or were secreted in plasma, etc. Those identified proteins contribute to a functional profile of the pituitary adenoma proteome. These data will be used to expand the proteome database of the human pituitary, which can be accessed in the website http://www.utmem.edu /proteomics.     

Vasopressin enhances a calcium current in human ACTH-secreting pituitary adenoma cells

Arginine vasopressin (AVP) is a potent secretagogue for adrenocorticotropin (ACTH) release from normal corticotropes and from ACTH-secreting pituitary adenoma cells. To explore the mechanism underlying this action, we investigated the effects of AVP on Ca2+-dependent action potentials and Ca2+ currents in cultured human ACTH-containing pituitary tumor cells (hACTH adenoma cells). Pituitary adenoma fragments removed at surgery from two patients with Cushing's disease were dispersed, and the isolated cells were grown in monolayer culture. Most of the cells showed ACTH immunoreactivity that persisted even after as much as 2 months in culture. Current clamp and voltage clamp recordings were carried out using the patch-clamp technique in the whole cell configuration. AVP produced an increase in the amplitude and duration of action potentials in these cells, and substantially enhanced the transient after-hyperpolarization after each spike. Under voltage the transient after-hyperpolarization after each spike. Under voltage clamp, hACTH adenoma cells showed two Ca2+ current components: a low-threshold, rapidly inactivating (T-type) current; and a higher threshold, slowly inactivating (L-type) current. AVP markedly increased the amplitude of the L-type current without affecting the T-type current. These data suggest that AVP may enhance Ca2+ entry associated with action potentials by potentiating the activity of L-type Ca2+ channels. The resulting rise in cytosolic free Ca2+ may be a key link in the process by which AVP stimulates ACTH release in the pituitary.     

Glycoprotein hormone alpha subunit as a marker of pituitary adenoma

Blood serum FSH, LH, prolactin and testosterone as well as urinary excretion of 17KS and 17-OHCS were determined in 8 patients with chromophobe pituitary adenomas treated by transphenoidal microsurgical removal or craniotomy with or without subsequent telecobalt therapy. It was found te disease tends to recur in the majority of patients despite the type of therapy. Recurrence is accompanied by gonadotropins hyposecretion, increase in prolactin secretion, secretory disorders in the gonads and adrenals; an increase in prolactin secretion is proportional to the intensity of the compression symptoms. Bromocriptine in a daily doses ranging from 5.0 to 7.5 mg decreases prolactin levels in the recurrent chromophobe pituitary adenomas and does not affect their proliferation.     

Differences in pathological findings and growth hormone responses in patients with growth hormone-producing pituitary adenoma.

Plasma growth hormone (GH) responses to various stimuli were examined in 21 patients with GH-producing pituitary adenomas, classified into three types by the immunohistochemistry of cytokeratin and the glycoprotein hormone alpha-subunit distribution. Seven type 1 adenomas were exclusively composed of cells in which the cytokeratin formed a dot-like pattern; they were chromophobic to hematoxylin and eosin (H&E), occasionally positive for GH, and almost completely negative for the alpha-subunit. Thirteen type 2 adenomas were composed of cells with cytokeratin that had a perinuclear distribution; they were eosinophilic to H&E, and diffusely positive for both GH and the alpha-subunit. One patient had a type 3 adenoma which had a mixed pattern of intracellular cytokeratin distribution and was chromophobic and eosinophilic to H&E. Clinically, type 1 is characterized by earlier onset, larger tumor size, and more frequent aggressive extension. Paradoxical GH responses to TRH and OGTT were seen in 1 of 6 patients (16.7%) of type 1 and 8 of 9 patients (88.9%) of type 2, and 0% of type 1 and 62.5% of type 2, respectively. Type 2 cases showed higher plasma GH response to GH-releasing hormone, and a tendency to greater suppression of plasma GH by bromocriptine compared with type 1. Octreotide acetate administration revealed that the nadir/basal ratio of plasma GH levels was 42.9 +/- 6.6% in type 1 and 13.5 +/- 5.8% in type 2. These results suggest that there is a pathophysiological difference between these two distinct types of GH-producing pituitary adenomas.     

Risk of second brain tumour after conservative surgery and radiotherapy for pituitary adenoma.

OBJECTIVE--To assess the risk of second brain tumour in patients with pituitary adenoma treated with conservative surgery and external beam radiotherapy. DESIGN--Long term follow up of a cohort of patients with pituitary adenoma and comparison of tumour occurrence with population incidence rates. SETTING--The Royal Marsden Hospital. SUBJECTS--334 patients with pituitary adenoma treated with conservative surgery and radiotherapy (median dose 45 Gy) and followed up for 3760 person years. MAIN OUTCOME MEASURES--Second intracranial tumour and systemic malignancy. RESULTS--Five patients developed a second brain tumour: two had astrocytoma, two meningioma, and one meningeal sarcoma. The cumulative risk of developing a second brain tumour over the first 10 years after treatment was 1.3% (95% confidence interval 0.4% to 3.9%) and over 20 years 1.9% (0.7% to 5.0%). The relative risk of a second brain tumour compared with the incidence in the normal population was 9.38 (3.05 to 21.89). There was no excess risk of any other type of second primary malignancy. CONCLUSIONS--There is an increased risk of second intracranial tumour in patients with pituitary adenoma treated with surgery and radiotherapy. Although radiation is likely to be the most important factor contributing to the excess risk, further study is required in a cohort of similar patients not receiving radiation.