1/46. growth hormone isoforms in a girl with gigantism.Several previous investigations have suggested that there may be different growth hormone isoforms in patients with acromegaly. We used three different site-specific monoclonal antibodies (MAbs) to investigate growth hormone (GH) isoforms in serum from an 8 year-old girl with a GH and prolactin secreting adenoma. The pattern of GH-immunoreactivity was dependent on the circumstances of collection. serum obtained after oral glucose had very little cross reactivity with MAb 352 although concentrations of up to 15 micrograms/l were found with two other MAbs, 033 and 665. MAb 352 does not recognize the 20,000 dalton isoform of GH (20K) while both MAb 033 and 665 do. The same pattern of GH immunoreactivity (low MAb 352, equal and higher MAb 033 and 665) was seen in other baseline samples. In contrast, samples obtained after TRH/GnRH showed immunoreactivity patterns expected for a mixture of 22,000 dalton isoform of GH (22K) with only a small amount of 20K. GH samples obtained during sleep showed both patterns with episodic peaks with equal immunoreactivity superimposed on the basal pattern (decreased activity with MAb 352). Affinity chromatography of basal samples showed that a portion of the GH immunoreactivity was neither 22K nor 20K, although in stimulated samples, over 70% of GH was 22K or 20K GH. In conclusion, the nature of GH isoforms present in serum varies with GH concentration. These differences may contribute to the known difficulty in correlating disease activity and random GH measurements in patients with GH secreting adenomas.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
2/46. Stereotactic intracavitary therapy of recurrent cystic craniopharyngioma by instillation of 90yttrium.Six consecutively presenting patients with craniopharyngiomas, (F:M = 4.2; mean age: 35.2 years, range 17-58) histologically proven by one or more previous operations, and with recurrence of a wholly or predominantly cystic nature, were treated by 90yttrium (90Y) radioisotope instillation into the cyst. Five patients had undergone external beam radiotherapy and the remaining patient had concomitant stereotactic radiosurgery to a co-existing solid component. Seven cysts in six patients have been treated. Five cysts, previously requiring repeated aspiration at intervals of 2-20 weeks have required no further surgical intervention following 90Y treatment (FU mean 3.5 years, range 1.2-7), although two of these required a second 90Y treatment. No patient developed a visual field defect or evidence of hypothalamic dysfunction. One patient died within a month of treatment from complications related to a solid recurrence. One patient developed a large solid/cystic recurrence at 4 months and died shortly thereafter from an unrelated cause. We summarize results from other series that have demonstrated the efficacy of this technique, usually as primary therapy, but this is the first series to demonstrate its usefulness as salvage therapy. The prospect of survival with good quality of life can be offered to patients with multiply recurrent disease who have exhausted all conventional means of treatment. In our experience intracavitary 90Y is a safe and highly effective means of controlling cystic recurrence in refractory craniopharyngioma. Some patients require more than one treatment.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
3/46. Prolactin-secreting pituitary adenoma in neuroleptic treated patients with psychotic disorder.Three patients with psychoses and concomitant prolactin-secreting pituitary tumours are described. patients A and B had bipolar and schizoaffective disorders, respectively. They had both been treated with neuroleptics for 20 years before the prolactinomas were revealed. Patient C developed a paranoid psychosis after two years of continuous bromocriptine treatment for a pituitary tumour. In patient A the prolactin level was successfully normalized and a good antipsychotic effect was maintained by combined therapy with haloperidol and quinagolide but not bromocriptine. In patient B the prolactinoma was removed by surgery, in view of the serious nature of the psychotic disorder, to avoid psychotic relapse by treatment with a dopamine agonist. In patient C a good result was obtained with the combination of clozapine and bromocriptine. These case reports support the view that neuroleptics being dopamine antagonists and dopamine agonistic agents which are the primary treatment of prolactinomas can cancel out each other's effects. The combination of clozapine and quinagolide is recommended as the treatment of choice for most patients.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
4/46. genetic heterogeneity and alterations in chromosome 9 loci in a localized region of a functional pituitary adenoma.The molecular alterations reported in pituitary adenomas include mutations at the G(s)alpha in somatotrophinomas, and hypermethylation of the p16 tumor suppressor gene. There are, however, no reports of genomic instability or intratumor genetic heterogeneity in pituitary adenomas. We have studied the microsatellite loci on the short arm of chromosome 9 (9p) and the dna fingerprinting pattern, of adjacent compartments, about 2 mm across, in a functional chromophobe pituitary adenoma secreting growth hormone and prolactin. The microsatellite loci were studied by PCR amplification using locus specific primers, while the dna fingerprinting pattern was studied by randomly amplified polymorphic DNA (RAPD) analysis. Normal leukocyte DNA was taken as control. Only one compartment (Ta) showed alterations in several of the microsatellite loci and in the RAPD pattern vis a vis corresponding normal DNA and also the other two compartments of the tumor. This provides evidence for the localized nature of genomic instability in this tumor.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
5/46. Corticotroph pituitary carcinoma: case report and literature review.Pituitary carcinomas, currently defined as primary adenohypophyseal neoplasms with evidence of either brain invasion or metastatic spread, are exceptionally rare. A case of corticotroph pituitary carcinoma is reported. A 17-year-old female first presented with an invasive and clinically non-functioning pituitary macroadenoma. The primary pituitary lesion lacked atypical histological features and retrospective immunohistochemical studies confirmed its corticotrophic nature. Repeated episodes of local recurrence followed together with the acquisition of severe Cushing's disease. Local disease control was not obtained despite repeated surgical decompression and courses of radiation therapy. Systemic dissemination with multiple bone metastases became manifest eleven years after the first presentation. Atypical histological features and Crooke's hyaline change were evident in both the recurrent and metastatic disease. She remains alive at last follow-up with severe complications relating to persisting sellar and metastatic disease and ongoing endocrine dysfunction. A further 32 cases of pituitary corticotroph carcinoma reported in English are reviewed to highlight the clinicopathological features of this rare form of pituitary neoplasm. Difficulties associated with the diagnosis and management of pituitary carcinoma are also discussed.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
6/46. paraganglioma of the pituitary fossa: diagnosis and management.paraganglioma of the sellar area is extremely rare with only six cases having been reported in the literature. Surgical removal of these tumors is difficult, and the transsphenoidal approach usually results in limited resection. Most authors who published reports on this tumor recommended radiation therapy after partial removal of the tumor. However, considering the benign nature of these tumors, the risk of radiation-induced endocrine insufficiency and optic neuropathy and the lack of proven effectiveness of radiotherapy, its value remains controversial. We describe a 48-year-old woman with parasellar paraganglioma who presented with headaches, visual loss and oligomenorrhea. magnetic resonance imaging (MRI) showed an invasive tumor in the sellar and parasellar areas which extended to both cavernous sinuses and compressed the optic chiasm and the left internal carotid artery. Surgery by the transsphenoidal approach enabled only limited biopsy of the tumor. The patient was reoperated by an extended pterional approach which resulted in a subtotal removal of the tumor and adequate decompression of the adjacent structures. She received no adjuvant treatment during the 8-year postsurgical follow-up and remained in good health. A repeated MRI showed no change in the size of the residual tumor. Contrary to the therapeutic recommendations described in previous reports, we favor postoperative adjuvant therapy only if the symptoms or signs of cranial nerve compression persist following maximal tumor removal, or if there is evidence of subsequent growth of residual tumor.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
7/46. Concomitant occurrence of macroprolactin, exercise-induced amenorrhea, and a pituitary lesion: a diagnostic pitfall. Case report.The authors report the case of a 37-year-old woman who presented with amenorrhea and an increased level of serum prolactin. Magnetic resonance images of the pituitary revealed a lesion with characteristics consistent with those of a microadenoma. Transsphenoidal exploration was performed, but a prolactinoma was not found. After endocrinological review, the patient's hyperprolactinemia was found to be caused by the presence of macroprolactin and her amenorrhea was due to intense exercise and low body weight. Macroprolactin is an isoform of prolactin that is variably reactive in assays for prolactin, but displays minimum bioactivity in vivo. patients with macroprolactin are mostly asymptomatic. This phenomenon may cause elevated prolactin values, which the authors view as apparent hyperprolactinemia. The presence of macroprolactin is an underrecognized problem, occurring in as many as 15 to 20% of patients with elevated prolactin values and often leading to unnecessary, expensive diagnostic procedures and inappropriate treatment. The presence of macroprolactin should always be suspected when the patient's clinical history or clinical or radiological data are incompatible with the prolactin value. physicians dealing with diagnosis and treatment of hyperprolactinemia (general practitioners, gynecologists, neurosurgeons, endocrinologists, and biochemists) should be aware of the potentially misleading nature of macroprolactin.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
8/46. Pituitary tumours are multiclonal from the outset: evidence from a case with dural metastases.In 1992 a 54-year-old man underwent transsphenoidal adenomectomy to remove a clinically nonfunctioning pituitary adenoma during which there was a transient cerebrospinal fluid (CSF) leak. He received radiotherapy to a small residual remnant. Follow-up magnetic resonance imaging (MRI) scan in 1997 showed an increase in the tumour in the pituitary stalk region and an additional intradural lesion at C1 level. In the absence of neurological symptoms and signs, an observational policy was followed. By 1999 the cervical dural lesion had enlarged and laminectomy was performed, during which three intradural lesions were removed. histology and immunohistochemistry of the metastases were identical to those of the initial pituitary adenoma. Follow-up MRI scan showed extension of the pituitary remnant above the chiasma, requiring transfrontal surgery. Operation was complicated by secondary brain haemorrhage from which the patient died. autopsy revealed a small amount of residual tumour at the top of the stalk and several small intradural tumour nodules at the level of the foramen magnum. Genetic analysis of the initial pituitary tumour identified significant allelic losses in keeping with its invasive nature, while that of the metastases indicated a separate clone as shown by retention of alleles lost in the primary tumour. The regrown pituitary tumour also appeared to be of a different clone to the initial tumour and the same as two of three of the first metastases (C1 level). The foramen magnum metastasis showed the same loss of heterozygosity (LOH) pattern as one of the original C1 metastases and the pituitary tumour tissue obtained at autopsy. We speculate that at the initial pituitary surgery, cells seeded into the CSF and grew in the dura. These cells were from a different clone, implying that the original pituitary tumour contained at least two clones, possibly three, providing evidence for the contemporaneous oligoclonality of the original pituitary tumour.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
9/46. Hepatocellular carcinoma metastasis in the pituitary gland: case report and review of the literature.Symptomatic pituitary metastases are uncommon and have been reported mainly in autopsy series. Although all types of malignancies can metastasize to the pituitary gland, a review of the literature has indicated that lung and breast carcinomas are the most frequent primary tumors while hepatocellular carcinoma metastasis has only recently been described. A 59-year-old man with abdominal pain and fever was admitted to our hospital. Hepatosplenomegaly was present without signs of ascites. Laboratory tests showed only abnormal hepatic biochemistry while the radiological studies revealed a solid mass occupying the left hepatic lobe. The patient underwent excision of the left hepatic lobe and was closely followed-up. Six months later he readmitted with headache and visual disturbances. MRI revealed a solid mass in the sella region pressing the optic chiasma. Transsphenoidal excision of the pituitary mass was followed and the histological examination of the tumor was compatible with hepatocellular carcinoma. Symptomatic pituitary metastases are uncommon and may be difficult to differentiate from pituitary adenomas. The present case emphasizes on the capricious nature of hepatocellular carcinoma and on the importance of the individualized therapeutic approach.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
10/46. Pilocytic astrocytoma of neurohypophysis.A case of pilocytic astrocytoma of neurohypophysis is presented. The clinical, pathological and MRI features of a rare tumor of the neurohypophysis are described. A 5-year-old girl presented with a 3 month history of lethargy, imbalance and visual disturbances. A MRI revealed a large suprasellar mass. Histopathological examination demonstrated a pilocytic astrocytoma. Its astrocytic nature was confirmed by positive immunostaining for GFAP and the findings of an electron microscopy.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
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