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PubMed1989

Pituitary adenocarcinoma in an acromegalic patient: response to bromocriptine and pituitary testing: a review of the literature on 36 cases of pituitary carcinoma.

There are 36 reported cases of metastatic pituitary carcinoma and almost half (44%) of these were associated with syndromes of hormonal hypersecretion. The case of a 56-year-old acromegalic man with cervical lymphatic and spinal metastases from a primary pituitary carcinoma is described. Elevated basal levels of plasma growth hormone (GH) and insulin growth factor-1/Somatomedin C (IGF-1/SmC) were found. GH levels did not increase after TRH or LHRH administration but decreased after L-Dopa and glucose. Immunostaining of the metastatic tumor for GH and electron microscopy findings confirmed the diagnosis of pituitary GH-secreting carcinoma. Striking clinical improvement and a 46% decrease in plasma GH levels were observed with bromocriptine treatment, although IGF-1/SmC levels increased during therapy. The clinical course of most reported cases of pituitary adenocarcinoma has been one of progressive intracranial expansion of a pituitary neoplasm. In only 25% were metastatic lesions discovered antemortem, and disabling symptomatology caused by metastases was rare. Only four previously reported patients of 36 with pituitary carcinoma had acromegaly.

Acromegaly↗
PubMed1975

Spontaneous infarction in pituitary tumors: neurologic and therapeutic aspects.

In addition to progressive endocrine dysfunction and progressive visual loss, pituitary neoplasms may annouce their presence by the more catastrophic alternative of spontaneous tumor infarction. In two patients reported, illness due to the spontaneous infraction of pituitary tumors was heralded by sudden onset of focal headache associated with diplopia. Stupor, confusion, and evidence of increased intracranial pressure occurred without subarachnoid hemorrhage or massive extrasellar extension of tumor. One patient developed inappropriate antidiuretic hormone secretion with spontaneous infarction in a large but clinically silent chromophobe adenoma. In both patients, skull x-rays suggested a long-standing intrasella mass. Both underwent prompt treatment with endocrinologic replacement therapy and subsequent successful transsphenoidal removal of voluminous, infarcted, pituitary masses.

Adenoma, Chromophobe↗
PubMed2005

Clinical significance of Ki-67 labeling index in pituitary macroadenoma.

The aim of our study was to investigate the correlation of the proliferative activity of pituitary neoplasms with clinical characteristics and recurrences. Tumor specimens were obtained from 44 consecutive patients with pituitary macroadenomas who underwent surgery between July 1998 and August 2003. Specimens were immediately fixed in 10% buffered formalin and then embedded in paraffin. The Ki-67 antigen was assessed by immumohistochemical analysis using the monoclonal antibody. We investigated the correlation of the Ki-67 labeling index with the following clinical and radiological characteristics: sex, age, presence or absence visual field defect, tumor classification, maximal tumor diameter, Hardy's classification, type of tumor, invasiveness, and recurrence. Our study suggests that the clinical characteristics such as visual field defect and recurrence are correlated with the high Ki-67 labeling index. No statistical differences were observed in the Ki-67 labeling index in relation to the following characteristics: sex, age, tumor classification, maximal tumor diameter, Hardy's classification, type of tumor, and invasiveness into the sphenoid sinus or cavernous sinus.

Adenoma↗
PubMed1983

Pituitary tumors and polycystic ovarian disease.

Three patients with polycystic ovarian disease and an associated pituitary tumor are described. Oligomenorrhea was present with galactorrhea in one patient, and amenorrhea was the presenting symptom in the other two. Diagnosis of the pituitary tumor was confirmed by computed tomography. Hyperprolactinemia (39.2 to 72.0 ng/ml) was present in two patients, both of whom responded promptly to the administration of bromocriptine. One nonhyperprolactinemic patient had an associated empty sella diagnosed with metrizamide cisternography. The literature of pituitary neoplasms in polycystic ovarian disease is reviewed and possible pathophysiology is discussed.

Adult↗
PubMedDate not supplied

[The importance of the team work in diagnosis of pituitary adenomas: the five-tier World Health Organization classification].

In the last ten years great changes occurred concerning the basic knowledge on pituitary adenomas. Many different classifications of pituitary adenomas were proposed. In 2000 World Health Organization accepted the five-tier classification of pituitary adenomas proposed by Kovacs and Horvath. It is based on clinical and biochemical results, neuroradiological imaging, operative findings, pathohistological examination, immunocytochemistry and electron microscopy studies on more than 10 000 surgically treated pituitary adenomas. Its importance is that it supplies the endocrinologist, neurosurgeon and oncologist with valuable information concerning the biological behavior, growth potential, treatment response and prognosis of pituitary adenomas. Due to the financial restraints, lack of facilities and unavailability of well trained personnel this five-tier classification cannot be fully implemented at our institution. Nonetheless, a perfectly useful diagnosis may be made in instances of limited sources. Clinical, biochemical, neuroradiological and intraoperative data coupled with basic histology are fundamental. Together with the novel biological techniques that provide the data on tumor's growth rate, aggressiveness and invasiveness, they ar necessary in establishing the correct diagnosis which will direct patient's future treatment. We strongly advocate in favor of this five-tier classification of pituitary neoplasms and hope it will reach the full implementation.

Adenoma↗
PubMed1996

The World Health Organization classification of adenohypophysial neoplasms. A proposed five-tier scheme.

BACKGROUND: Although numerous attempts have been made, the classification of pituitary neoplasms remains controversial. METHODS: The present proposal is based on correlative clinical and pathologic (histologic, immunocytochemical, and electron microscopic) studies of more than 8000 surgically removed human pituitary tumors. RESULTS: Anterior pituitary tumors have been variously classified on the basis of their clinical presentation, biochemical findings, histology (growth pattern, tinctorial characteristics), proliferation indices, immunocytochemical profile, and ultrastructural features. Herein we propose a five-tier classification, clinicopathologic in nature, which focuses on endocrine activity, imaging, operative findings, histology, immunocytochemistry, and ultrastructure. The integration of these five complementary approaches into what is fundamentally a pathologic classification is as practical as it is novel. Its importance lies in the fact that the collected data provide valuable information to the clinical endocrinologist, neurosurgeon, and oncologist involved in the assessment of a tumor's biologic behavior, growth potential, therapeutic responsiveness, and prognosis. Due to financial restraints, lack of facilities, and unavailability of well trained personnel, we realize that at present the five approaches cannot be fully implemented in all institutions. Nonetheless, clinical and biochemical data, imaging, and operative findings, as well as basic histologic parameters are generally readily available. Collectively they are indispensable in establishing the correct diagnosis and in directing patient management. Conversely, the cost-effectiveness of immunocytochemistry and electron microscopy is debatable in that their performance and interpretation requires time, financial resources, and expertise. Nonetheless, it should be clear that any correlation between endocrine activity, growth potential, morphologic features, immunocytochemical profile, and ultrastructural features provides greater insight into the pathobiology of adenohypophysial tumors than is gained by routine histology alone. Thus we feel justified in including immunocytochemical and ultrastructural investigation of pituitary tumors in a modern classification. At present, more sophisticated molecular biologic methods represent investigative tools that play no significant role in the classification. CONCLUSIONS: A five-tier classification of adenohypophysial neoplasms based on clinical and biochemical results, imaging, operative findings, histology, immunocytochemistry, and electron microscopy is proposed. It is recommended to the World Health Organization for acceptance.

Humans↗
PubMed1978

Recent advances in diagnosis and management of galactorrhea.

Using prolactin suppression (L-dopa) and provocative (thorazine) tests along with the clomid test the intactness of hypothalamico-pituitary axis was assessed in a group of eight patients with galactorrhea syndrome. Pituitary neoplasm was suspected in three cases on the basis of elevated plasma prolactin and its abnormal response to L-dopa, thorazine, and clomid tests. Trans-sphenoidal exploration of the pituitary gland in these three cases confirmed the diagnosis. In these cases, however, the commonly used parameters for evaluation of the pituitary gland (skull X ray, visual field measurement, echoencephalogram, etc.) failed to reveal the presence of the pituitary lesions. In two of the three cases, normal menses recurred following extirpation of the tumors and conception was achieved successfully. In the remaining patient the operation failed to remove the entire pituitary lesion and it was necessary to irradiate the pituitary gland as the patient continued to have persistent galactorrhea and hyperprolactinemia. The importance of the prolactin assay, and its response to stimulation and suppression tests for proper evaluation of galactorrhea was fully discussed.

Adult↗
PubMed1978

Incidence of pituitary tumors following adrenalectomy. A long-term follow-up study of patients treated for Cushing's disease.

The long-term follow-up of 21 patients who had undergone bilateral adrenalectomy for Cushing's disease has revealed eight definite and two suspected cases of pituitary tumors. The average time from adrenalectomy to the diagnosis of the pituitary tumor was 6 1/2 years, with a range of 1 1/2 to 12 years. The incidence of tumors in this study (38%) is higher than that reported by others and may reflect (1) that none of these patients received pituitary irradiation in addition to adrenalectomy, (2) the length of follow-up, and (3) the high index of suspicion and early diagnosis of pituitary tumors in recent years. These data raise the question of whether bilateral adrenalectomy alone is an acceptable form of therapy for Cushing's disease. For patients treated in this way, a life-long commitment should be made to undergo annual reexamination for the possible occurrence of a pituitary neoplasm.

Adenoma↗
PubMed1996

Diabetes mellitus in a dog with a growth hormone-producing acidophilic adenoma of the adenohypophysis.

A 9-year-old male Doberman Pinscher was referred to the Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, for polyuria/polydipsia, anorexia, and vomiting. Laboratory examination of blood and urine revealed hyperglycemia, glucosuria, and acidosis. Diabetes mellitus was diagnosed but was very resistant to subsequent insulin treatment. At the owners' request, the dog was euthanatized and a postmortem examination was performed. In addition to hepatic, pancreatic, and renal changes compatible with diabetes mellitus, an acidophilic adenoma of the adenohypophysis was found. Immunohistochemical staining for growth hormone, adrenocorticotropic hormone, and prolactin showed a strong immunolabeling for growth hormone within the cytoplasm of the tumor cells. Although growth hormone level was not measured in the plasma, our findings suggest that the diabetes mellitus in this dog was caused by excess growth hormone secreted by the pituitary neoplasm.

Adenoma, Acidophil↗
PubMed1987

Endocrine inactive pituitary carcinoma metastasizing to cervical lymph nodes: a case report.

A 64-year-old woman experienced an episode of disorientation in relation to time, place, and people, as well as of visual defect and impaired balance. Physical examination showed a bitemporal hemianopsia and truncal ataxia. Computerized tomography of the skull revealed a sellar mass consistent with the diagnosis of pituitary adenoma. The patient progressively lost consciousness and died. At postmortem examination, a pituitary neoplasm with arachnoid metastases was present. Metastatic cervical lymph nodes were also detected. Histologic aspects of the primary tumor and of lymph node metastases were quite similar. Immunohistochemical investigation revealed the epithelial origin of the neoplasm and failed to disclose endocrine activity. At ultrastructural examination, the cells of the primary tumor and of the metastases lacked specific granules. These findings support the evidence of a primary metastasizing pituitary carcinoma.

Carcinoma↗
PubMed2001

Pigmented papillary epithelial neoplasm of the pituitary fossa: a distinct lesion of uncertain histogenesis.

Primary pigmented intracranial neoplasms are strikingly uncommon. The differential diagnosis is limited and includes both epithelial and nonepithelial tumors, most of which arise within or near the ventricular system. The authors describe a 42-year-old man who presented with a pigmented papillary epithelial lesion that arose within the sella and exhibited suprasellar extension and bony erosion. Following external beam radiotherapy and multiple surgical resections, tumor growth became rapid, necessitating additional debulking procedures. Pathologic evaluation of subsequent lesional tissue samples revealed an anaplastic lesion with malignant epithelial and spindle cell components. Occasional epithelial cells showed features reminiscent of the original papillary lesion, whereas others exhibited oncocytic morphologic features. This case represents the only report, to our knowledge, of a pigmented papillary epithelial neoplasm arising within the pituitary fossa. Although the histogenesis of this tumor is enigmatic, this appears to be a distinct lesion characterized by aggressive growth and the capacity for anaplastic progression.

Adult↗
PubMed1976

Pituitary thyrotropic tumour secondary to long-standing primary hypothyroidism.

Pituitary neoplasms in primary myxoedema are rare and previously reported cases have mostly been described as chromophobe adenomas. None of them were subjected to modern methods of study. A 26 year-old woman with untreated primary hypothyroidism developed a pituitary tumour which produced bitemporal hemianopsia. Histochemical and ultrastructural studies characterized the tumour cells as thyrotrops. The secretory granules present had a mean diameter of 110 mum and were membrane-bound and surrounded by clear halos. Many of the tumour cells were actively secreting. They had reduced numbers of granules, possessed expanded Golgi complexes, abundant rough endoplasmic reticulum and free ribosomes. Cytoplasmic microfilaments were also seen. A possible mechanism of production of this tumour is discussed.

Adenoma↗
PubMed1978

Coexisting pituitary adenomas and partially empty sellas.

seventeen cases of coexisting secreting pituitary adenomas and partially empty sellas are presented. The location of the cisternal invagination into the sella was not helpful in predicting the location of the tumor. In patients with endocrine indication of a secreting pituitary neoplasm, the finding of a partially empty sella should not contradict the diagnosis.

Adenoma↗
PubMed1986

Plasma ACTH levels and beta-endorphin-like immunoreactivity following administration of luteinizing hormone-releasing hormone in Nelson's syndrome.

The effect of LH-RH (25 micrograms as a single i.v. bolus) on plasma corticotropin (ACTH) levels and beta-endorphin-like immunoreactivity was studied at 30 and 60 min in eight women with Nelson's syndrome. Plasma ACTH concentrations increased in three of them, while beta-endorphin-like immunoreactivity, measured in six cases, rose significantly at 30 min in all the patients under investigation. In the control group containing seven women with Nelson's syndrome, placebo (0.9% sodium chloride) administration did not induce any significant changes in ACTH concentrations or in beta-endorphin-like immunoreactivity. Our results suggest that a paradoxical stimulatory influence of LH-RH on pituitary Nelson's adenomas may play an important role in the adenoma hormonal activity and, perhaps, growth. Such an effect could be responsible for a rapid development of some pituitary neoplasms during pregnancy.

Adenoma↗
PubMed1998

Comparative genomic hybridization analysis of nonfunctioning pituitary tumors.

Clinically nonfunctioning pituitary adenomas constitute about one third of pituitary neoplasms and are considered monoclonal tumors. The molecular mechanisms of tumorigenesis in these neoplasms are poorly understood, as evidenced by the paucity of reported somatic genetic alterations. Furthermore, the somatic mutations detected to date were primarily ascribed to candidate genes or chromosomal regions: gsp, ras, p53 mutations, and allelic losses of 11q and 13q. To gain insight into which chromosomal regions bear genes involved in nonfunctioning pituitary tumorigenesis, we examined 23 such tumors by comparative genomic hybridization. Four tumors showed no genetic abnormality, and the rest (17 of 23, 74%) exhibited at least one chromosomal region of abnormality. Gains and losses affected all chromosomes (except for chromosome 14). Notably, 8 of 23 tumors (34.7%) displayed sex chromosome and chromosome 18 aberrations (amplifications or deletions). Nonrandom DNA amplification of sub-chromosomal regions on 4q, 5q (5q13-->5q23), 9p (9p21-->9pter), 13q (13q21-->13q32), and 17q were detected in 10-30% of the tumors. Noteworthy, no tumor displayed deletion of 11q, the MEN1 gene locus. These findings suggest that genes localized to previously undescribed chromosomal regions play a role in the tumorigenesis of nonfunctioning pituitary adenomas.

Adenoma↗
PubMed1991

The role of hypothalamic hormones in the pathogenesis of pituitary adenomas.

There is evidence that hypothalamic hormones can regulate hormone secretion by pituitary adenomas. Hormone release by adenomas can be stimulated by hypothalamic releasing peptides; several hypothalamic inhibitory hormones or their analogues are used in the therapy of pituitary tumors to suppress hormone secretion and, in some cases, to reduce tumor size. A role for hypothalamic hormones in the development and growth of pituitary tumors has also been suggested by the association of pituitary adenomas with tumors producing hypothalamic hormones. In particular, tumors producing growth hormone-releasing hormone (GRH) or corticotropin-releasing hormone (CRH) have been associated with hyperplasia of their target adenohypophysial cells; a few have had pituitary neoplasms. Investigations have shown that some adenohypophysial cells respond to sustained stimulation by hypothalamic peptides with cell proliferation, however, it was not proven that the sustained stimulation resulted in the development of tumors. Recently, an animal model of disease was provided by mice transgenic for GRH. At 8 months of age, the mice developed pituitary mammosomatotroph hyperplasia; mice older than 12 months developed pituitary mammosomatotroph adenoma. It is suggested that continued hormonal stimulation plays a role in tumorigenesis, probably by promotion of cell replication.

Adenoma↗