Three patients with rare epidermoid cyst in the callosal region are described, two adjacent and one in the corpus callosum. Computed tomography revealed atypical features, i.e. a large, well-defined high density mass unenhanced postcontrast and a well-defined hypodense mass with marginal calcification in one case each. Such a diffuse high-density mass may be caused by hemorrhage, highly concentrated protein or calcification of keratinized debris within the cyst. Marginal calcification may occur for unknown reasons. The cysts were subtotally removed.
GH-producing adenomas clinically are endocrine-active tumors accompanied with acromegaly in most instances. However, GH-producing adenomas apparently unassociated with acromegaly, or so-called silent somatotroph adenomas (SSA), have recently been reported but rarely. The reported cases are characterized by normal or slightly elevated serum levels of GH but without acromegaly. Tumor cells contain moderate, trace or no GH immunoreactivity. We experienced 7 cases of SSA which were not always similar in morphology and pathogenetic mechanism. They could be further divided into the following 3 subtypes. Subtype 1 (N = 2): a moderate number of cells were immunopositive for GH, and GH mRNA was also expressed in moderate or numerous cells. Densely granulated cells were noted. It is assumed that inhibition of hormone release into circulation. Subtype 2 (N = 3): a small number of cells were immunopositive for GH, while GH mRNA was expressed in numerous tumor cells. They were sparsely granulated cells containing fibrous bodies. These findings suggest that posttranslational processing of the gene product may be defective. Subtype 3 (N = 2): Only a scattered number of cells were immunopositive for GH and GH mRNA was co-localized in immunopositive cells. They were sparsely granulated cells containing poorly developed organelles that did not resemble those of typical sparsely granulated GH cells. The findings indicate that adenoma cells are largely immature with minimal GH lineage differentiation.
A gangliocytoma in the sellar region is very rare. We report a case of an intrasellar gangliocytoma com plicated by pituitary adenoma presenting with acromegaly. A 52-year-old female was admitted to our hospital with headache, mild acromegaly, and bitemporal hemianopsia, and endocrinological study found a high serum level of growth hormone (GH). A computed tomographic scan revealed a tumor in the sellar region, which was almost totally removed by trans-sphenoidal surgery . Histo logical examination of the resected specimen showed diffuse, chromophobe-type pituitary adenoma , partially containing cholesterin clefts. Areas of clusters of dysmorphic neurons, adjacent to or mixed with pituitary adenoma, were diagnosed as gangliocytoma.The immunohistochemical exami nation showed GH-releasing hormone (GRH)-positive dysmorphic neurons and GH-positive pituitary adenoma. We consider that the trophic effect of GRH secreted by the neurons of GRH-producing in trasellar gangliocytoma probably caused the GH-producing pituitary adenoma.
A 38-year-old male presented with a cystic lesion at the foramen magnum due to intracranial dis semination from a pituitary adenoma. The primary tumor had required reoperation for regrowth twice . The tumor at the foramen magnum was removed surgically. Two smaller solid tumors were located in the left parietal convexity and the right temporal lobe. The former tumor was also removed surgically and the latter was observed. Histological examination showed the typical characteristics of pituitary adenoma in both surgical specimens. Immunohistochemical staining with MIB-1 and p53 antibodies showed low (< 1%) and negative reaction. Patients with pituitary adenoma , even benign tumors, must be carefully followed up for signs of metastasis.
Thirty-one consecutive cases of pituitary adenoma in acromegalic patients were studied by immunohistochemistry. All adenomas contained cells immunoreactive with the anti-alpha-subunit of gonadotropic hormones (alpha; 0.6-53% of tumor cells) as well as with anti-growth hormone (GH; 4-74% of tumor cells). In serial section study, most cells immunoreactive with anti-alpha were identical to cells immunoreactive with anti-GH. There was a positive correlation between the percentages of cells immunoreactive for alpha in GH cells [alpha (%)/GH(%)] and those for prolactin (PRL) in immunoreactive tumor cells (PRL(%)/[PRL(%) + GH(%)]) in mixed GH cell-PRL cell adenomas, suggesting that the alpha-subunit may play a role in emergence of PRL cells.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.